CAMBRIDGE ENGLISH 7. Which enzyme digests protein in the stomach?

A. Amylase
SCHOOL, SILLOD B. Lipase
SUMMER VACATION WORKSHEET 1 C. Pepsin
Grade : X D. Maltase
Sub.: Science
(Ch. 1 Life Process in Living Organism) 8. The opening and closing of stomata is controlled
by:
General Instructions: A. Epidermal cells
 All the questions are compulsory. B. Guard cells
 Worksheet to be submitted by 10/05/2025 C. Xylem vessels
D. Phloem tissues
QA. Multiple Choice Questions: 9. Which of the following is the correct equation for
photosynthesis?
1. Which of the following is not a life process?
A. CO₂ + H₂O → C₆H₁₂O₆ + O₂
A. Respiration
B. C₆H₁₂O₆ + O₂ → CO₂ + H₂O
B. Reproduction
C. CO₂ + O₂ → C₆H₁₂O₆ + H₂O
C. Excretion
D. CO₂ + H₂O → C₆H₆ + O₂
D. Photosynthesis
10. Which part of nephron filters the blood?
2. The basic unit of kidney is:
A. Loop of Henle
A. Neuron
B. Collecting duct
B. Nephron
C. Bowman's capsule
C. Alveoli
D. Tubule
D. Ureter
11. The main function of hemoglobin is to:
3. The process of breakdown of glucose in absence
A. Digest food
of oxygen is called:
B. Transport oxygen
A. Glycolysis
C. Transport nitrogen
B. Fermentation
D. Store energy
C. Photosynthesis
D. Aerobic respiration
12. The process of removal of metabolic waste from
the body is called:
4. Which organ helps in the removal of carbon
A. Nutrition
dioxide from the body?
B. Respiration
A. Kidney
C. Excretion
B. Liver
D. Reproduction
C. Lungs
D. Skin
13. Where does the digestion of protein begin in
the human body?
5. Which of the following organisms use cutaneous
A. Mouth
respiration?
B. Esophagus
A. Earthworm
C. Stomach
B. Fish
D. Small intestine
C. Human
D. Bird
14. Which blood vessel carries oxygenated blood
from lungs to heart?
6. Which plant tissue transports water?
A. Pulmonary artery
A. Phloem
B. Pulmonary vein
B. Xylem
C. Aorta
C. Parenchyma
D. Vena cava
D. Collenchyma
 respiration?
15. Which part of the digestive system absorbs A. Lactic acid
nutrients? B. Ethanol
A. Stomach C. Carbon dioxide
B. Small intestine D. Urea
C. Large intestine
D. Esophagus 24. Which plant structure helps in water loss?
A. Guard cells
16. Which of the following is an autotroph? B. Xylem
A. Mushroom C. Stomata
B. Paramecium D. Phloem
C. Mango tree
D. Amoeba 25. Which part of nephron reabsorbs water and
salts?
17. Fat digestion starts in: A. Glomerulus
A. Mouth B. Tubule
B. Stomach C. Ureter
C. Small intestine D. Bowman’s capsule
D. Liver
26. Which is a heterotrophic mode of nutrition?
18. What is the function of bile juice? A. Photosynthesis
A. Breaks proteins B. Chemosynthesis
B. Emulsifies fats C. Saprotrophic
C. Digests starch D. Autotrophic
D. Absorbs water
27. Anaerobic respiration in yeast produces:
19. Which organ secretes insulin? A. Lactic acid
A. Liver B. Alcohol and CO₂
B. Pancreas C. Urea
C. Kidney D. Oxygen
D. Stomach
28. The liver converts excess amino acids into:
20. Respiration is a process in which: A. Glucose
A. Energy is stored B. Alcohol
B. Energy is released C. Urea
C. Food is produced D. Glycogen
D. Blood is purified
29. Which blood vessels carry blood away from the
21. Which of the following is not involved in human heart?
excretory system? A. Veins
A. Kidney B. Arteries
B. Ureter C. Capillaries
C. Urethra D. Lymph vessels
D. Lungs
30. Root pressure helps in:
22. Photosynthesis takes place in which cell A. Digestion
organelle? B. Transport of water
A. Mitochondria C. Photosynthesis
B. Ribosomes D. Excretion
C. Chloroplast
D. Nucleus 31. How many chambers are there in a human
heart?
23. Which molecule is the end product of aerobic A. 2
B. 3
C. 4 40. What prevents food from entering windpipe?
D. 5 A. Epiglottis
B. Trachea
32. The inner wall of the small intestine has: C. Uvula
A. Cilia D. Glottis
B. Villi
C. Flagella 41. Which vessel has valves?
D. Hairs A. Artery
B. Vein
33. Which component of blood fights infection? C. Capillary
A. RBC D. Aorta
B. Platelets
C. Plasma 42. Which cell organelle is known as the
D. WBC powerhouse of the cell?
A. Nucleus
34. Which enzyme in saliva digests starch? B. Mitochondria
A. Pepsin C. Ribosome
B. Trypsin D. Golgi body
C. Amylase
D. Lipase 43. What is the role of phloem in plants?
A. Transport water
35. What is the role of alveoli in lungs? B. Transport minerals
A. Blood storage C. Transport food
B. Exchange of gases D. Support plant body
C. Digestion
D. Circulation 44. Which organ removes urea from the blood?
A. Liver
36. The energy currency of the cell is: B. Kidney
A. DNA C. Lungs
B. RNA D. Heart
C. ATP
D. ADP 45. The waste product of respiration is:
C A. O₂
37. Excretion in amoeba occurs through: B. CO₂
A. Contractile vacuole C. H₂O
B. Nephridia D. Glucose
C. Flame cells
D. Nephrons 46. The site of gaseous exchange in human lungs is:
A. Bronchi
38. Which form of nutrition is seen in fungi? B. Trachea
A. Holozoic C. Alveoli
B. Saprotrophic D. Pleura
C. Autotrophic
D. Parasitic 47. Which component of blood helps in clotting?
A. Plasma
B. WBC
C. Platelets
39. Water moves up in plants due to: D. RBC
A. Root pressure
B. Transpiration pull 48. Enzymes are:
C. Capillarity A. Fats
D. All of the above B. Proteins
C. Carbohydrates
D. Nucleic acids 57. The contraction and relaxation of muscles to
move food is called:
49. Which part of the brain controls involuntary A. Peristalsis
actions? B. Assimilation
A. Cerebrum C. Digestion
B. Cerebellum D. Ingestion
C. Medulla
D. Pons 58. Glucose is broken down in mitochondria to
release:
50. Which organ excretes sweat? A. Oxygen
A. Skin B. Energy
B. Liver C. Protein
C. Kidney D. Vitamins
D. Lungs
59. What type of blood flows through pulmonary
51. Which mineral is essential for hemoglobin artery?
formation? A. Oxygenated
A. Calcium B. Deoxygenated
B. Iodine C. Mixed
C. Iron D. Pure
D. Magnesium
60. Which organ filters the blood in the human
52. Which is the end product of protein digestion? body?
A. Fatty acids A. Liver
B. Glycerol B. Heart
C. Amino acids C. Kidney
D. Glucose D. Lungs

53. Which mode of nutrition does Amoeba follow? 61. In plants, food is transported through:
A. Autotrophic A. Xylem
B. Parasitic B. Phloem
C. Holozoic C. Parenchyma
D. Saprophytic D. Collenchyma

54. Which organ system transports oxygen and 62. The green pigment in leaves is:
nutrients? A. Carotene
A. Respiratory B. Xanthophyll
B. Circulatory C. Chlorophyll
C. Digestive D. Anthocyanin
D. Excretory
63. Lymph differs from blood in lacking:
55. Which organ produces bile? A. Plasma
A. Stomach B. RBCs
B. Liver C. WBCs
C. Gallbladder D. Water
D. Pancreas
64. The smallest blood vessels are:
56. What is the main function of RBCs? A. Arteries
A. Blood clotting B. Veins
B. Fighting infection C. Capillaries
C. Oxygen transport D. Venules
D. Producing hormones
65. The organ that stores bile is: B. ATP
A. Pancreas C. Water
B. Liver D. Sunlight
C. Gallbladder
D. Kidney 74. Which cell part is responsible for cellular
respiration?
66. The number of nephrons in each kidney is A. Ribosome
approximately: B. Nucleus
A. 10,000 C. Mitochondria
B. 1 million D. Lysosome
C. 100,000
D. 10 million 75. Where is urea produced in the human body?
A. Kidney
67. The phloem transports food from: B. Liver
A. Roots to leaves C. Skin
B. Leaves to storage organs D. Bladder
C. Soil to roots
D. Flowers to fruits 76. Which part of the digestive system has finger-
like projections?
68. Photosynthesis does not occur in: A. Stomach
A. Green leaves B. Esophagus
B. Green stems C. Small intestine
C. Roots D. Large intestine
D. Algae
77. Which type of blood cells destroy bacteria?
69. Which waste is excreted through the lungs? A. RBC
A. Ammonia B. Platelets
B. Urea C. Plasma
C. CO₂ D. WBC
D. Salt
78. What is the function of stomata?
70. What helps in clotting of blood? A. Reproduction
A. Platelets B. Gas exchange
B. Plasma C. Respiration
C. WBC D. Absorption of minerals
D. RBC
79. The longest part of the alimentary canal is:
71. The waste product of anaerobic respiration in A. Esophagus
humans is: B. Large intestine
A. Alcohol C. Small intestine
B. CO₂ D. Stomach
C. Lactic acid
D. Ammonia 80. Kidney failure leads to accumulation of:
A. Glucose
72. During exhalation, the ribs: B. Oxygen
A. Move up and out C. Urea
B. Move down and in D. Carbon dioxide
C. Remain fixed
D. Expand 81. What happens to diaphragm during inhalation?
A. Relaxes
73. What is the main source of energy for all life B. Contracts and flattens
processes? C. Becomes dome-shaped
A. Food D. None of the above
 B. Earthworm
82. The process of photosynthesis requires: C. Cockroach
A. Water, carbon dioxide, light D. Human
B. Oxygen, sunlight, chlorophyll
C. Water, oxygen, glucose 91. How many molecules of ATP are generated by
D. CO₂, chlorophyll, starch aerobic respiration per glucose molecule?
A. 2
83. Which structure prevents backflow of blood in B. 4
veins? C. 36
A. Artery wall D. 1
B. Valves
C. Capillaries 92. The blood vessel entering the glomerulus is:
D. Pressure A. Renal vein
B. Afferent arteriole
84. Breakdown of food in the mouth is: C. Efferent arteriole
A. Only mechanical D. Vena cava
B. Only chemical
C. Both mechanical and chemical 93. What is emulsification?
D. None A. Protein digestion
B. Breaking of fats into droplets
85. What is the role of mucus in the stomach? C. Absorption of glucose
A. Digest proteins D. Secretion of hormones
B. Absorb nutrients
C. Protect stomach lining 94. Plant excretion is mainly through:
D. Neutralize acid A. Roots
B. Fruits
86. Which process does not require energy? C. Leaves
A. Active transport D. Flowers
B. Photosynthesis
C. Diffusion 95. Which blood component transports hormones?
D. Endocytosis A. Plasma
B. RBC
87. ATP stands for: C. Platelets
A. Adenosine Triphosphate D. WBC
B. Adenosine Tetraphosphate
C. Adenine Trisugar 96. The breathing rate in humans increases due to:
D. None A. Lack of water
B. Increased CO₂
88. Which element is necessary for photosynthesis? C. Low nitrogen
A. Sodium D. Low oxygen
B. Magnesium
C. Iron 97. Which organ is responsible for ultrafiltration?
D. Calcium A. Heart
B. Glomerulus
89. Which enzyme is absent in gastric juice? C. Liver
A. Pepsin D. Lungs
B. Lipase
C. Amylase 98. Which of the following stores urine?
D. HCl A. Urethra
B. Kidney
90. Which organism has no specialized organs for C. Bladder
excretion? D. Ureter
A. Hydra
99. Exhaled air contains more: C. WBC
A. O₂ D. All
B. CO₂
C. N₂ 108. Plants get rid of waste by:
D. Hydrogen A. Active transport
B. Exhalation
100. Blood pressure is measured using: C. Shedding leaves
A. Thermometer D. Sweating
B. Stethoscope
C. Sphygmomanometer 109. Where does gas exchange take place in plants?
D. Barometer A. Roots
B. Flowers
101. Photosynthesis is a/an: C. Stomata
A. Catabolic process D. Stem
B. Endothermic process
C. Exothermic process 110. The part of alimentary canal that receives bile:
D. Neutral process A. Stomach
B. Large intestine
102. Which vessel carries blood from kidney to C. Small intestine
heart? D. Esophagus
A. Renal artery
B. Aorta 111. Which component gives red color to blood?
C. Renal vein A. Plasma
D. Pulmonary vein B. Hemoglobin
C. Iron
103. Which enzyme is responsible for digesting D. Myoglobin
fats?
A. Pepsin 112. The main function of xylem:
B. Amylase A. Transport food
C. Lipase B. Transport water
D. Maltase C. Transport air
D. Support stem
104. In humans, the respiratory pigment is:
A. Hemocyanin 113. Protein digestion starts in:
B. Hemoglobin A. Mouth
C. Myoglobin B. Esophagus
D. Chlorophyll C. Stomach
D. Small intestine
105. Most of the reabsorption in nephron occurs in:
A. Bowman’s capsule 114. Urea is a:
B. Collecting duct A. Carbohydrate
C. Proximal tubule B. Protein
D. Loop of Henle C. Nitrogenous waste
D. Hormone
106. Starch is broken into sugar by:
A. Lipase 115. Which organ produces digestive enzymes and
B. Amylase hormones?
C. Pepsin A. Liver
D. Trypsin B. Kidney
C. Pancreas
107. Which blood cells help in immunity? D. Bladder
A. RBC
B. Platelets 116. Which part of the brain controls breathing?
A. Cerebrum
B. Cerebellum 125. What causes muscle cramps during heavy
C. Medulla exercise?
D. Thalamus A. Ethanol
B. Glucose
117. What prevents food from entering the C. Lactic acid
trachea? D. Carbon dioxide
A. Larynx
B. Epiglottis 126. Which is the universal energy currency?
C. Pharynx A. NADH
D. Alveoli B. FAD
C. ATP
118. What type of nutrition is seen in Cuscuta? D. GTP
A. Saprophytic
B. Autotrophic 127. Which of the following helps in double
C. Parasitic circulation?
D. Symbiotic A. 2-chambered heart
B. 3-chambered heart
119. Which cells lack nuclei? C. 4-chambered heart
A. WBC D. Open heart
B. RBC
C. Platelets 128. The major excretory product in human urine
D. All is:
A. Ammonia
120. Diaphragm is made of: B. Uric acid
A. Bone C. Urea
B. Ligament D. CO₂
C. Muscle
D. Cartilage 129. Which hormone regulates glucose level?
A. Insulin
121. Fat digestion is completed in: B. Adrenaline
A. Mouth C. Thyroxine
B. Stomach D. Estrogen
C. Large intestine
D. Small intestine 130. In which structure does filtration of blood
occur in nephron?
122. Which blood component carries nutrients? A. Tubule
A. RBC B. Bowman’s capsule
B. WBC C. Loop of Henle
C. Platelets D. Collecting duct
D. Plasma
131. Which chamber of the heart receives
123. Which part of nephron is cup-shaped? oxygenated blood from the lungs?
A. Glomerulus A. Right atrium
B. Collecting duct B. Left atrium
C. Tubule C. Left ventricle
D. Bowman’s capsule D. Right ventricle

124. Excess glucose is stored in liver as: 132. Water absorption in roots occurs through:
A. Starch A. Active transport
B. Insulin B. Diffusion
C. Glycogen C. Osmosis
D. Glucagon D. Filtration
 141. Plants store glucose in the form of:
133. Which substance protects the inner lining of A. Glycogen
the stomach? B. Starch
A. Acid C. Protein
B. Mucus D. Fat
C. Pepsin
D. Bile 142. Veins carry blood:
A. Under high pressure
134. The large surface area of alveoli helps in: B. Under low pressure
A. Reducing heat C. With high oxygen
B. Quick blood circulation D. Without plasma
C. Efficient gas exchange
D. Absorption of nutrients 143. Which of the following is a parasitic plant?
A. Cactus
135. What regulates the opening and closing of B. Mushroom
stomata? C. Cuscuta
A. Chloroplasts D. Neem
B. Guard cells
C. Xylem 144. Which structure increases the surface area of
D. Phloem small intestine?
A. Villi
136. Which part of nephron reabsorbs water and B. Cilia
nutrients? C. Mucus
A. Loop of Henle D. Enzymes
B. Collecting duct
C. Tubule 145. Lactic acid is produced during:
D. Glomerulus A. Aerobic respiration
B. Glycolysis
137. Which of the following carries oxygen-rich C. Anaerobic respiration
blood? D. Photosynthesis
A. Pulmonary artery
B. Pulmonary vein 146. Carbon dioxide enters leaves through:
C. Vena cava A. Cuticle
D. Right ventricle B. Lenticels
C. Stomata
138. Bile helps in digestion of: D. Xylem
A. Carbohydrates
B. Proteins 147. The functional unit of kidney is:
C. Fats A. Ureter
D. Vitamins B. Glomerulus
C. Nephron
139. Photosynthesis produces: D. Bladder
A. Water
B. Oxygen 148. Lungs are present in:
C. Carbon dioxide A. Thoracic cavity
D. Lactic acid B. Abdominal cavity
C. Pelvic cavity
140. Root pressure helps in: D. Cranial cavity
A. Transpiration
B. Water transport 149. Plants release excess water through:
C. Food transport A. Photosynthesis
D. Gas exchange B. Excretion
C. Transpiration
D. Absorption C. Arterioles
D. Venules
150. Gaseous exchange in insects occurs through:
A. Skin 159. Gastric juice contains:
B. Spiracles A. Pepsin, HCl, mucus
C. Lungs B. Lipase and bile
D. Gills C. Amylase and lipase
D. Trypsin and bile
151. The site of digestion and absorption is:
A. Stomach 160. A by-product of respiration in yeast:
B. Esophagus A. Lactic acid
C. Large intestine B. Alcohol
D. Small intestine C. Glucose
D. Oxygen
152. What does not take part in respiration?
A. Mitochondria 161. Which component regulates heartbeat?
B. Glucose A. Brain
C. Ribosomes B. Spinal cord
D. Oxygen C. Pacemaker
D. Lungs
153. Which gland secretes insulin?
A. Liver 162. Which structure acts as the filtering unit of the
B. Pituitary kidney?
C. Pancreas A. Renal vein
D. Thyroid B. Nephron
C. Glomerulus
154. Pulmonary vein carries blood to the: D. Loop of Henle
A. Lungs
B. Right atrium 163. The air sacs in lungs are called:
C. Left atrium A. Bronchi
D. Right ventricle B. Trachea
C. Alveoli
155. Starch in food is first broken down in: D. Bronchioles
A. Stomach
B. Mouth 164. Which chamber of the heart pumps
C. Liver oxygenated blood?
D. Small intestine A. Right ventricle
B. Left ventricle
156. The red pigment in blood is: C. Left atrium
A. Hemocyanin D. Right atrium
B. Hemoglobin
C. Chlorophyll 165. Excretion in amoeba occurs through:
D. Myosin A. Contractile vacuole
B. Nephridia
157. What maintains the shape of alveoli? C. Flame cells
A. Cartilage D. Lungs
B. Surfactant
C. Mucus 166. What is the role of ureter?
D. Muscle A. Produces urea
B. Stores urine
158. Which blood vessel connects arteries to veins? C. Carries urine to bladder
A. Lymph D. Filters blood
B. Capillaries
167. The pigment essential for photosynthesis is: B. Capillaries
A. Chlorophyll C. Arteries
B. Hemoglobin D. Venules
C. Xanthophyll
D. Anthocyanin 176. Exhaled air contains:
A. Less CO₂
168. Exchange of gases in alveoli is by: B. More CO₂
A. Osmosis C. No CO₂
B. Diffusion D. No oxygen
C. Active transport
D. Filtration 177. Most oxygen in blood is transported as:
A. O₂ dissolved in plasma
169. Pancreatic juice contains enzymes for B. O₂ bound to hemoglobin
digestion of: C. O₂ in WBCs
A. Proteins only D. O₂ in platelets
B. Fats only
C. All food types 178. Which part of the brain controls involuntary
D. Vitamins actions?
A. Cerebrum
170. Respiration in plants occurs in: B. Cerebellum
A. Day only C. Medulla oblongata
B. Night only D. Hypothalamus
C. Day and night
D. Never 179. The part of nephron where filtration of blood
takes place:
171. Which enzyme digests proteins in the A. Tubule
stomach? B. Loop of Henle
A. Lipase C. Glomerulus
B. Pepsin D. Collecting duct
C. Amylase
D. Maltase 180. Inhalation brings in:
A. Carbon dioxide
172. What is the function of saliva? B. Water vapor
A. Absorbs water C. Nitrogen
B. Emulsifies fats D. Oxygen
C. Breaks starch
D. Digests proteins 181. Which part of the nephron collects the filtered
urine?
173. Which part of blood helps in clotting? A. Glomerulus
A. Plasma B. Tubule
B. RBC C. Collecting duct
C. WBC D. Loop of Henle
D. Platelets
182. The process by which green plants make food
174. The excretory product of birds is: is called:
A. Ammonia A. Respiration
B. Urea B. Transpiration
C. Uric acid C. Photosynthesis
D. Carbon dioxide D. Germination

175. Which blood vessels carry blood away from 183. Which of the following organisms respires
the heart? through gills?
A. Veins A. Earthworm
B. Fish C. Pepsin
C. Frog D. Amylase
D. Amoeba
192. Plants excrete waste through:
184. Which is the first enzyme that acts on A. Lungs
carbohydrates in digestion? B. Stomata
A. Pepsin C. Skin
B. Lipase D. Phloem
C. Amylase
D. Trypsin 193. The process of eliminating undigested food is:
A. Assimilation
185. Which process maintains water balance in the B. Excretion
body? C. Ingestion
A. Photosynthesis D. Egestion
B. Excretion
C. Respiration 194. Which part of the digestive system absorbs
D. Circulation water?
A. Stomach
186. Which organ stores bile? B. Small intestine
A. Liver C. Large intestine
B. Pancreas D. Esophagus
C. Stomach
D. Gallbladder 195. Which molecule stores energy for cellular
processes?
187. The pigment that gives red color to blood is: A. DNA
A. Myoglobin B. ATP
B. Hemoglobin C. RNA
C. Hemocyanin D. Enzyme
D. Erythrin
196. Which organ filters blood in the human body?
188. The lungs are protected by: A. Heart
A. Skull B. Lungs
B. Rib cage C. Kidneys
C. Backbone D. Liver
D. Muscles
197. Anaerobic respiration produces:
189. Blood vessels with valves to prevent backflow A. Water
are: B. Oxygen
A. Arteries C. Lactic acid
B. Veins D. ATP only
C. Capillaries
D. Lymph vessels 198. What is absorbed by roots from soil?
A. Carbon dioxide
190. How many chambers does a human heart B. Oxygen
have? C. Water and minerals
A. 2 D. Glucose
B. 3
C. 4 199. Which structure helps in clotting of blood?
D. 5 A. RBC
B. WBC
191. What breaks down fats in the small intestine? C. Platelets
A. Bile D. Plasma
B. Trypsin
200. Arteries carry blood: C. Semilunar
A. Towards the heart D. Aortic
B. Away from the heart
C. To the lungs 209. Which enzyme digests proteins in the
D. To the stomach stomach?
A. Trypsin
201. The function of hemoglobin is to: B. Lipase
A. Transport nutrients C. Pepsin
B. Fight infection D. Amylase
C. Carry oxygen
D. Digest food 210. Which gas is used in photosynthesis?
A. Oxygen
202. Which part of the brain controls breathing B. Nitrogen
rate? C. Hydrogen
A. Cerebrum D. Carbon dioxide
B. Cerebellum
C. Medulla 211. Transpiration helps in:
D. Hypothalamus A. Food production
B. Protein digestion
203. Which of the following is not a life process? C. Water transport
A. Respiration D. Storing energy
B. Excretion
C. Thinking 212. The basic unit of kidney is:
D. Nutrition A. Alveolus
B. Nephron
204. The phloem transports: C. Neuron
A. Water D. Glomerulus
B. Nutrients
C. Oxygen 213. Photosynthesis takes place in which part of
D. Food the plant?
A. Roots
205. Amoeba obtains its food by: B. Stem
A. Absorption C. Leaves
B. Diffusion D. Flowers
C. Phagocytosis
D. Osmosis 214. The part of the nephron where filtration
occurs:
206. Which plant tissue transports water? A. Loop of Henle
A. Phloem B. Tubule
B. Xylem C. Glomerulus
C. Parenchyma D. Collecting duct
D. Collenchyma
215. Blood from the lungs enters the heart into the:
207. Gaseous exchange in humans occurs in: A. Right atrium
A. Bronchi B. Right ventricle
B. Alveoli C. Left atrium
C. Diaphragm D. Left ventricle
D. Trachea
216. The total number of ATP molecules produced
208. The valve between left atrium and left in aerobic respiration from one glucose molecule is:
ventricle is: A. 2
A. Tricuspid B. 4
B. Bicuspid C. 38
D. 32 225. Water absorption in plants takes place
through:
217. The blood vessel that carries oxygenated A. Stomata
blood from lungs to heart is: B. Root hairs
A. Pulmonary artery C. Leaves
B. Aorta D. Flowers
C. Pulmonary vein
D. Vena cava 226. Blood vessels that connect arteries to veins:
A. Capillaries
218. The food pipe is also known as: B. Aorta
A. Trachea C. Pulmonary vessels
B. Esophagus D. Lymph nodes
C. Alimentary canal
D. Pharynx 227. The pigment responsible for trapping solar
energy in plants:
219. The primary product of photosynthesis is: A. Carotene
A. Oxygen B. Xanthophyll
B. Glucose C. Chlorophyll
C. Carbon dioxide D. Hemoglobin
D. ATP
228. Excretory product in amoeba is:
220. Which of the following contains enzymes for A. Ammonia
digestion in the stomach? B. Urea
A. Mucus C. Uric acid
B. Hydrochloric acid D. Water
C. Pepsin
D. Bile 229. Respiration that occurs in absence of oxygen
is:
221. The large intestine mainly absorbs: A. Aerobic
A. Proteins B. Cellular
B. Fats C. Anaerobic
C. Water D. External
D. Glucose
230. The main role of bile in digestion is:
222. The contraction of diaphragm helps in: A. Protein digestion
A. Digestion B. Neutralization of acid
B. Inhalation C. Emulsification of fats
C. Exhalation D. Carbohydrate digestion
D. Circulation
231. During heavy exercise, which acid is produced
223. Which gas is a byproduct of photosynthesis? in muscles?
A. Carbon dioxide A. Citric acid
B. Nitrogen B. Hydrochloric acid
C. Oxygen C. Lactic acid
D. Hydrogen D. Uric acid

224. Which system is responsible for removing 232. The function of xylem is to transport:
nitrogenous waste? A. Food
A. Circulatory B. Water and minerals
B. Digestive C. Hormones
C. Excretory D. Gases
D. Respiratory
233. The plant structure for gaseous exchange is:
A. Xylem D. Right ventricle
B. Root hair
C. Stomata 242. Which of the following is a parasitic plant?
D. Cuticle A. Cactus
B. Algae
234. Which blood component fights infection? C. Cuscuta
A. RBC D. Fern
B. Platelets
C. Plasma 243. Exhaled air contains more:
D. WBC A. Oxygen
B. Carbon dioxide
235. Which enzyme breaks down starch? C. Nitrogen
A. Pepsin D. Water vapor
B. Lipase
C. Amylase 244. Which blood vessel carries blood from the
D. Trypsin heart to the lungs?
A. Aorta
236. The smallest blood vessels are: B. Pulmonary vein
A. Arteries C. Pulmonary artery
B. Veins D. Vena cava
C. Capillaries
D. Aorta 245. Which organ removes excess amino acids from
the body?
237. The pancreas secretes: A. Liver
A. Insulin B. Kidney
B. Bile C. Intestine
C. Saliva D. Pancreas
D. Pepsin
246. In which form is glucose stored in animals?
238. Which of the following is not involved in A. Starch
excretion in humans? B. Cellulose
A. Skin C. Glycogen
B. Liver D. Sucrose
C. Lungs
D. Stomach 247. The substance used to test for the presence of
starch in leaves is:
239. Photosynthesis occurs fastest in: A. Benedict’s solution
A. Green light B. Iodine
B. Blue light C. Alcohol
C. Red light D. Lime water
D. Dark
248. Urea is produced in the:
240. The end product of digestion of proteins is: A. Kidney
A. Amino acids B. Liver
B. Glucose C. Heart
C. Fatty acids D. Lungs
D. Water
249. The wall of arteries is:
241. Which chamber of the heart receives A. Thin and elastic
deoxygenated blood from the body? B. Thick and elastic
A. Left atrium C. Thick and rigid
B. Right atrium D. Thin and rigid
C. Left ventricle
250. Which is not a function of blood? C. Amoeba
A. Transport of gases D. Plants
B. Control of hormones
C. Protection against disease 259. The flap that covers the windpipe during
D. Regulation of body temperature swallowing is:
A. Trachea
251. Which part of alimentary canal absorbs B. Epiglottis
digested food? C. Glottis
A. Stomach D. Pharynx
B. Large intestine
C. Small intestine 260. Which of these is not a product of anaerobic
D. Rectum respiration?
A. Ethanol
252. Respiration is a process in which: B. Carbon dioxide
A. Energy is stored C. Lactic acid
B. Glucose is converted to protein D. Oxygen
C. Energy is released
D. Oxygen is used up 261. Which cells have no nucleus in human blood?
A. WBC
253. The enzyme lipase digests: B. RBC
A. Fats C. Platelets
B. Proteins D. Plasma
C. Carbohydrates
D. Vitamins 262. Which component of the blood helps in
clotting?
254. The lungs are spongy because of: A. Red blood cells
A. Pleural fluid B. White blood cells
B. Bronchioles C. Platelets
C. Alveoli D. Plasma
D. Diaphragm
263. What causes the movement of water in
255. Translocation in plants occurs through: xylem?
A. Xylem A. Active transport
B. Phloem B. Root pressure and transpiration pull
C. Cambium C. Diffusion
D. Parenchyma D. Capillary action only

256. What is the main function of lymph? 264. The liver converts excess amino acids into:
A. Transport gases A. Glucose
B. Blood clotting B. Glycogen
C. Return tissue fluid to blood C. Urea
D. Carry urea D. Fatty acids

257. The excretory organ in earthworm is: 265. The structure where gaseous exchange occurs
A. Kidney in the human lungs is:
B. Nephridia A. Bronchi
C. Flame cells B. Alveoli
D. Malpighian tubules C. Trachea
D. Bronchioles
258. Glucose is converted into ethanol and carbon
dioxide in: 266. Which structure prevents the mixing of
A. Liver oxygenated and deoxygenated blood in humans?
B. Yeast A. Valves
B. Septum B. Plant will gain water
C. Atria C. Photosynthesis will decrease
D. Ventricles D. Respiration will stop

267. Which among these is a form of anaerobic 274. What is the role of pepsin in digestion?
respiration? A. Breaks down carbohydrates
A. Glucose → CO₂ + H₂O + Energy B. Breaks down proteins
B. Glucose → Lactic acid + Energy C. Emulsifies fats
C. Glucose → Oxygen + ATP D. Absorbs water
D. Glucose → Pyruvate + Energy
275. Which gas is required for aerobic respiration?
268. (Analytical) Which process ensures A. Nitrogen
unidirectional flow of food in the alimentary canal? B. Carbon dioxide
A. Digestion C. Oxygen
B. Peristalsis D. Hydrogen
C. Absorption
D. Assimilation 276. Which of these structures carry blood away
from the heart?
269. Where is bile stored after its formation in the A. Veins
liver? B. Capillaries
A. Stomach C. Arteries
B. Gall bladder D. Lymph vessels
C. Pancreas
D. Duodenum 277. Which of the following is a heterotroph?
A. Grass
270. What is the correct sequence in the passage of B. Mushroom
food through the human body? C. Algae
A. Mouth → Esophagus → Stomach → Small D. Neem tree
Intestine → Large Intestine
B. Esophagus → Mouth → Stomach → Large 278. Urea is transported in blood to:
Intestine → Small Intestine A. Liver
C. Mouth → Stomach → Esophagus → Small B. Kidneys
Intestine → Large Intestine C. Lungs
D. Mouth → Esophagus → Small Intestine → D. Skin
Stomach → Large Intestine
279. (Application-based) A student chews bread for
271. Which part of the nephron is primarily a long time and notices a sweet taste. This is due
responsible for reabsorption? to:
A. Glomerulus A. Acid in saliva
B. Collecting duct B. Conversion of starch to sugar
C. Tubule C. Breakdown of proteins
D. Bowman's capsule D. Digestion by pepsin

272. The pigment responsible for photosynthesis is 280. Which component is absent in phloem?
located in the: A. Sieve tubes
A. Mitochondria B. Companion cells
B. Cell wall C. Tracheids
C. Cytoplasm D. Phloem parenchyma
D. Chloroplast
281. What controls the opening and closing of
273. (Critical Thinking) If stomata of a plant remain stomata?
closed during the day, what will likely happen? A. Guard cells
A. Photosynthesis will increase B. Xylem
C. Root pressure A. Resin
D. Mesophyll cells B. Latex
C. Urea
282. (Critical Thinking) A person’s urine contains D. Gum
high glucose level. This may indicate:
A. Kidney stones 290. Which element is essential for chlorophyll
B. Diabetes formation?
C. Liver damage A. Calcium
D. Anemia B. Nitrogen
C. Magnesium
283. The major nitrogenous waste excreted by D. Phosphorus
humans is:
A. Ammonia 291. What is the function of the villi in the small
B. Uric acid intestine?
C. Urea A. Increase absorption area
D. Nitrite B. Filter waste
C. Secrete hormones
284. The muscular structure that helps in breathing D. Transport oxygen
is:
A. Ribs 292. Which part of the human body has the highest
B. Diaphragm blood pressure?
C. Lung A. Right atrium
D. Pleura B. Left ventricle
C. Pulmonary vein
285. Which organ secretes insulin? D. Right ventricle
A. Liver
B. Kidney 293. Fat digestion begins in the:
C. Pancreas A. Stomach
D. Intestine B. Mouth
C. Small intestine
286. (Analytical) In a closed terrarium, if plants are D. Large intestine
placed without any animals, the oxygen level at
night will: 294. Which of the following has no digestive
A. Increase enzyme?
B. Decrease A. Bile
C. Remain same B. Saliva
D. Fluctuate rapidly C. Gastric juice
D. Pancreatic juice
287. Which part of the alimentary canal absorbs
most nutrients? 295. (Critical Thinking) Why do athletes experience
A. Large intestine muscle cramps after vigorous exercise?
B. Stomach A. Accumulation of glucose
C. Small intestine B. Accumulation of lactic acid
D. Esophagus C. Deficiency of water
D. Accumulation of urea
288. Haemoglobin has high affinity for:
A. Carbon dioxide 296. What is the function of valves in veins?
B. Oxygen A. Increase blood pressure
C. Nitrogen B. Prevent backflow of blood
D. Ammonia C. Enhance oxygenation
D. Produce red blood cells
289. Which of these is not a plant excretory
product? 297. The human heart is made up of:
A. Smooth muscle D. Ureter
B. Skeletal muscle
C. Involuntary striated muscle 306. Transpiration helps in:
D. Voluntary striated muscle A. Digestion
B. Excretion
298. Root pressure is maximum: C. Transport of food
A. During transpiration D. Cooling the plant
B. In the daytime
C. During night 307. The functional unit of lungs is:
D. During wilting A. Bronchi
B. Bronchioles
299. Which enzyme in saliva digests starch? C. Alveoli
A. Pepsin D. Trachea
B. Lipase
C. Amylase 308. What do plants excrete through stomata?
D. Trypsin A. Urea
B. Oxygen
300. Where does the exchange of gases occur in C. Glucose
plants? D. Gum
A. Xylem
B. Lenticels and stomata 309. In which form is food transported in phloem?
C. Phloem A. Amino acids
D. Chloroplasts B. Starch
C. Sucrose
301. (Application) During breathing out, the ribs: D. Fructose
A. Move upwards
B. Move inwards and downwards 310. The exchange of gases in humans is facilitated
C. Stay fixed by:
D. Expand A. Diffusion
B. Osmosis
302. Lymph is part of which system? C. Active transport
A. Circulatory D. Filtration
B. Digestive
C. Nervous 311. The inner wall of small intestine has:
D. Excretory A. Glands only
B. Smooth lining
303. The kidneys help maintain: C. Villi
A. Blood sugar D. Microtubules
B. Hormone levels
C. Water and salt balance 312. The breakdown of pyruvate to give carbon
D. Oxygen levels dioxide, water, and energy takes place in:
A. Cytoplasm
304. (Critical Thinking) A plant kept in a dark room B. Ribosome
will: C. Mitochondria
A. Perform more respiration than photosynthesis D. Nucleus
B. Perform more photosynthesis than respiration
C. Not respire 313. In the human digestive system, hydrochloric
D. Stop absorbing water acid is secreted by:
A. Salivary glands
305. Which structure filters blood in the nephron? B. Pancreas
A. Loop of Henle C. Gastric glands
B. Tubule D. Liver
C. Glomerulus
314. Which component of blood fights against 322. Which chamber of the human heart receives
infection? oxygenated blood from the lungs?
A. Platelets A. Left atrium
B. Red blood cells B. Right atrium
C. Plasma C. Left ventricle
D. White blood cells D. Right ventricle

315. Which of the following helps in emulsification 323. Which organ removes nitrogenous waste from
of fats? the blood?
A. Pepsin A. Liver
B. Trypsin B. Kidney
C. Bile C. Skin
D. Amylase D. Lungs

316. What type of respiration occurs in yeast? 324. The function of guard cells is to:
A. Aerobic A. Produce food
B. Anaerobic B. Absorb nutrients
C. Both A and B C. Open and close stomata
D. None D. Absorb water

317. The process by which green plants prepare 325. What is the main function of hemoglobin?
their own food is called: A. Blood clotting
A. Transpiration B. Immunity
B. Respiration C. Oxygen transport
C. Photosynthesis D. Nutrient absorption
D. Germination
326. (Application-Based) Which of these activities
318. Which organ has both endocrine and exocrine leads to increased carbon dioxide production in the
functions? body?
A. Liver A. Resting
B. Pancreas B. Sleeping
C. Kidney C. Running
D. Stomach D. Sitting

319. Blood in pulmonary artery is: 327. Which organ secretes digestive enzymes and
A. Pure and oxygenated hormones?
B. Impure and oxygenated A. Stomach
C. Pure and deoxygenated B. Pancreas
D. Impure and deoxygenated C. Liver
D. Small intestine
320. The walls of arteries are:
A. Thin and non-elastic 328. In which part of the digestive system is water
B. Thick and elastic mainly absorbed?
C. Thin and porous A. Small intestine
D. Thick and porous B. Esophagus
C. Large intestine
321. (Critical Thinking) If the epiglottis fails to D. Rectum
function, what might happen during swallowing?
A. Digestion will increase 329. A nephron is found in the:
B. Food may enter windpipe A. Liver
C. Enzyme secretion stops B. Lung
D. Peristalsis is reversed C. Kidney
D. Heart
330. What is the main purpose of respiration? 338. In fish, the organ responsible for respiration is:
A. Absorption A. Lungs
B. Growth B. Gills
C. Energy production C. Trachea
D. Reproduction D. Air sacs

331. Which part of the plant is mainly responsible 339. What ensures blood flows in one direction in
for transpiration? the heart?
A. Roots A. Septum
B. Xylem B. Arteries
C. Phloem C. Valves
D. Leaves D. Veins

332. In humans, the exchange of gases occurs in: 340. The process of excretion in amoeba occurs
A. Bronchi through:
B. Alveoli A. Contractile vacuole
C. Bronchioles B. Pseudopodia
D. Trachea C. Nucleus
D. Mitochondria
333. Which of the following vessels carry blood
towards the heart? 341. (Analytical) If xylem of a plant is removed, it
A. Arteries will affect:
B. Veins A. Transport of food
C. Capillaries B. Absorption of minerals
D. Arterioles C. Transport of water
D. Photosynthesis
334. Which of the following enzymes digests
proteins in the stomach? 342. Bile is produced in the:
A. Amylase A. Stomach
B. Lipase B. Gallbladder
C. Trypsin C. Liver
D. Pepsin D. Pancreas

335. Glomerulus is located in the: 343. The removal of metabolic waste is known as:
A. Bowman's capsule A. Excretion
B. Ureter B. Digestion
C. Renal pelvis C. Respiration
D. Loop of Henle D. Circulation

336. Which among the following substances is not 344. Which among these is the smallest unit of
reabsorbed by the kidney tubules? kidney function?
A. Glucose A. Nephron
B. Amino acids B. Bowman’s capsule
C. Urea C. Ureter
D. Water D. Glomerulus

337. Which of the following is not a product of 345. The energy currency of the cell is:
anaerobic respiration in yeast? A. Glucose
A. Ethanol B. DNA
B. Carbon dioxide C. ATP
C. Lactic acid D. RNA
D. Energy
346. What is the function of the large intestine? A. Deoxygenated blood to lungs
A. Absorbs glucose B. Oxygenated blood from lungs
B. Absorbs proteins C. Oxygenated blood to lungs
C. Absorbs water D. Deoxygenated blood to heart
D. Absorbs vitamins
355. The main nitrogenous waste excreted by birds
347. Plants release most of their water into the air is:
through: A. Ammonia
A. Photosynthesis B. Urea
B. Respiration C. Uric acid
C. Transpiration D. Nitrite
D. Diffusion
356. Which of these is a raw material for
348. Which part of nephron filters the blood? photosynthesis?
A. Collecting duct A. Oxygen
B. Glomerulus B. Carbon dioxide
C. Loop of Henle C. Protein
D. Ureter D. Nitrogen

349. The food in the stomach is churned with 357. In plants, food is transported through:
gastric juice to form: A. Xylem
A. Bolus B. Phloem
B. Mucus C. Cortex
C. Chyme D. Cambium
D. Villi
358. (Application-Based) After drinking a lot of
350. Which of these is a vestigial organ in humans? water, urine becomes:
A. Liver A. More concentrated
B. Appendix B. Less concentrated
C. Pancreas C. Yellow
D. Kidney D. Rich in urea

351. (Critical Thinking) In a dry environment, desert 359. What is the role of stomata in plants?
plants minimize water loss through: A. Absorption of water
A. Broad leaves B. Excretion of wastes
B. Thin cuticle C. Gaseous exchange
C. Sunken stomata D. Nutrient transport
D. Excess transpiration
360. The opening and closing of stomata depends
352. Which component of blood transports oxygen? on:
A. White blood cells A. Light and temperature
B. Platelets B. CO₂ concentration
C. Plasma C. Water pressure in guard cells
D. Hemoglobin D. Oxygen availability

353. Which one of the following organisms does 361. (Critical Thinking) Which of the following will
not breathe through lungs? be most affected if mitochondria are removed from
A. Fish a cell?
B. Human A. Respiration
C. Cat B. Excretion
D. Bird C. Digestion
D. Circulation
354. The pulmonary vein carries:
362. The process by which plants lose water in the B. Increased flow of deoxygenated blood to the
form of water vapor is known as: lungs
A. Photosynthesis C. Decreased oxygen levels in the blood
B. Respiration D. Difficulty in pumping blood to the lungs
C. Transpiration
D. Absorption 370. The main function of the large intestine is to:
A. Absorb water and salts
363. The movement of water in plants occurs B. Absorb glucose
primarily through: C. Produce digestive enzymes
A. Xylem D. Neutralize stomach acid
B. Phloem
C. Parenchyma 371. Which of the following statements is true
D. Epidermis about veins?
A. They carry blood away from the heart
364. Which of the following is not a function of the B. They carry oxygenated blood
human circulatory system? C. They have thick walls
A. Transport of nutrients D. They have valves to prevent backflow
B. Transport of oxygen
C. Transport of hormones 372. Which of the following is a major product of
D. Oxygen production aerobic respiration?
A. Lactic acid
365. In humans, oxygen is transported by: B. Ethanol
A. Platelets C. Carbon dioxide and water
B. White blood cells D. Oxygen and glucose
C. Red blood cells
D. Plasma 373. The function of villi in the small intestine is to:
A. Secrete enzymes
366. In the process of digestion, which enzyme B. Increase the surface area for absorption
breaks down starch? C. Store food temporarily
A. Amylase D. Regulate the movement of food
B. Lipase
C. Pepsin 374. In plants, water is absorbed by the:
D. Trypsin A. Roots
B. Leaves
367. Which structure in the human digestive system C. Stems
is primarily responsible for absorbing most of the D. Flowers
nutrients?
A. Stomach 375. (Critical Thinking) If a plant is kept in a
B. Large intestine completely dark room, what would happen to its
C. Small intestine process of photosynthesis?
D. Liver A. It would stop completely
B. It would increase rapidly
368. Which of the following is the primary role of C. It would continue but at a slower rate
the diaphragm during breathing? D. It would convert sunlight into stored energy
A. Expelling air from the lungs
B. Drawing air into the lungs 376. The energy released by the breakdown of
C. Mixing gases in the lungs glucose in cells is stored in the form of:
D. Preventing water from entering the lungs A. DNA
B. RNA
369. (Critical Thinking) If the blood pressure in the C. ATP
pulmonary artery increases, which of the following D. Glucose
would most likely be the result?
A. Increased flow of oxygenated blood to the lungs 377. The digestive enzyme pepsin is secreted by:
A. Pancreas D. Large flowers
B. Salivary glands
C. Stomach 385. The function of the contractile vacuole in
D. Small intestine amoeba is to:
A. Digest food
378. The most common nitrogenous waste excreted B. Excrete waste
by humans is: C. Remove excess water
A. Uric acid D. Store food
B. Ammonia
C. Urea 386. (Analytical) If the number of platelets in the
D. Creatinine human body decreases, what is most likely to
occur?
379. The liquid part of the blood that helps in the A. Increased risk of infections
transportation of nutrients, hormones, and waste B. Difficulty in forming blood clots
products is: C. Decreased oxygen supply to tissues
A. Red blood cells D. Difficulty in absorbing nutrients
B. White blood cells
C. Plasma 387. The process by which plants take in carbon
D. Platelets dioxide and release oxygen is called:
A. Respiration
380. The main function of the heart's right side is to B. Photosynthesis
pump: C. Transpiration
A. Oxygenated blood to the lungs D. Germination
B. Oxygenated blood to the body
C. Deoxygenated blood to the lungs 388. Which type of blood vessel is responsible for
D. Deoxygenated blood to the body carrying blood to the heart?
A. Arteries
381. The main function of phloem in plants is to B. Veins
transport: C. Capillaries
A. Water D. Venules
B. Minerals
C. Sugar 389. The breakdown of glucose to release energy
D. Oxygen occurs in the presence of:
A. Oxygen
382. Which process converts glucose into ethanol B. Nitrogen
and carbon dioxide in yeast? C. Carbon dioxide
A. Fermentation D. Water
B. Respiration
C. Photosynthesis 390. The left atrium of the heart receives
D. Transpiration oxygenated blood from the:
A. Lungs
383. The upper surface of the leaf mainly consists B. Body
of: C. Right atrium
A. Stomata D. Right ventricle
B. Epidermal cells
C. Mesophyll cells 391. (Critical Thinking) If the guard cells of a plant
D. Vascular bundles do not function properly, what would most likely
happen?
384. Which of the following is an example of a A. Decreased rate of transpiration
structural adaptation in plants for photosynthesis? B. Increased water loss through stomata
A. Thin leaves C. Increased oxygen absorption
B. Broad leaves D. Reduced absorption of water
C. Long roots
392. The process of filtration of blood in the C. Transport nutrients
kidneys takes place in the: D. Regulate blood flow
A. Glomerulus
B. Loop of Henle 400. The root hairs in plants are responsible for:
C. Nephron A. Photosynthesis
D. Ureter B. Absorption of water
C. Transport of food
393. Which part of the brain regulates involuntary D. Respiration
activities like heartbeat and breathing?
A. Cerebrum 401. (Critical Thinking) If a person breathes in air
B. Cerebellum with low oxygen concentration, what will happen
C. Medulla to the body?
D. Hypothalamus A. The body will become more active
B. Oxygen uptake in tissues will decrease
394. During photosynthesis, the energy absorbed C. Heart rate will decrease
from sunlight is stored in the form of: D. The body will adapt to the oxygen shortage
A. ATP
B. Glucose 402. In the human circulatory system, which of the
C. Oxygen following is responsible for blood clotting?
D. Water A. White blood cells
B. Platelets
395. In humans, digestion of proteins begins in the: C. Plasma
A. Mouth D. Red blood cells
B. Small intestine
C. Stomach 403. The major process in which cells produce
D. Large intestine energy without oxygen is:
A. Photosynthesis
396. The amount of oxygen used by the body in a B. Aerobic respiration
given time is called: C. Anaerobic respiration
A. Breathing rate D. Transpiration
B. Oxygen debt
C. Oxygen consumption 404. The most efficient method of obtaining energy
D. Respiratory rate in humans is:
A. Fermentation
397. The green pigment responsible for B. Aerobic respiration
photosynthesis in plants is: C. Anaerobic respiration
A. Chlorophyll D. Glycolysis
B. Carotene
C. Xanthophyll 405. Which of these is a common characteristic of
D. Phycobilin all living organisms?
A. Ability to move
398. (Analytical) What will happen if a plant is B. Ability to respond to stimuli
exposed to light for an extended period during the C. Ability to produce food
night? D. Ability to live without water
A. Photosynthesis will continue
B. The plant will not grow 406. Which of the following is true about the
C. Respiration will stop excretory system in humans?
D. The plant will decompose A. Kidneys filter waste from the blood
B. Lungs remove nitrogenous waste
399. The primary function of the white blood cells C. Skin secretes hormones
is to: D. Liver produces urine
A. Transport oxygen
B. Fight against diseases 407. (Analytical) If a plant is placed in a sealed jar
with no light, what will happen to the levels of
carbon dioxide and oxygen inside the jar over time? 414. Which part of the nephron is responsible for
A. Oxygen levels will decrease, carbon dioxide levels filtration?
will increase A. Collecting duct
B. Oxygen levels will increase, carbon dioxide levels B. Bowman's capsule
will decrease C. Loop of Henle
C. Both oxygen and carbon dioxide levels will D. Ureter
increase
D. Both oxygen and carbon dioxide levels will remain 415. The pancreas produces which digestive
constant enzyme?
A. Pepsin
408. Which of the following substances is not found B. Amylase
in the excretory products of humans? C. Lipase
A. Urea D. Both B and C
B. Water
C. Oxygen 416. Which part of the plant cell contains
D. Uric acid chlorophyll?
A. Mitochondria
409. Which part of the plant is responsible for the B. Cytoplasm
synthesis of food through photosynthesis? C. Chloroplast
A. Leaf D. Nucleus
B. Root
C. Stem 417. Which waste is excreted by the skin?
D. Flower A. Oxygen
B. Urea
410. Which of these blood vessels carries blood C. Sweat (water + salts)
away from the heart? D. Bile
A. Veins
B. Arteries 418. What is the main function of the alveoli in
C. Capillaries lungs?
D. Lymph vessels A. Digestion
B. Filtration
411. The liquid part of blood that is primarily C. Gaseous exchange
responsible for transporting nutrients, gases, and D. Blood purification
wastes is:
A. Plasma 419. Which blood vessels allow exchange of
B. White blood cells materials between blood and tissues?
C. Red blood cells A. Arteries
D. Platelets B. Capillaries
C. Veins
412. Which chamber of the heart pumps D. Venules
oxygenated blood to the body?
A. Right atrium 420. Which is not a product of anaerobic
B. Left atrium respiration in muscles?
C. Right ventricle A. Lactic acid
D. Left ventricle B. ATP
C. Oxygen
413. Which of the following structures helps in the D. Carbon dioxide
upward movement of water in plants?
A. Phloem 421. (Analytical) A person’s urine shows a high
B. Guard cells amount of glucose. What could be the likely
C. Xylem vessels condition?
D. Stomata A. Kidney stones
B. Diabetes C. Absorbs water
C. Anemia D. Secretes insulin
D. Dehydration
430. In which form is excess glucose stored in the
422. Which component of blood fights infections? human body?
A. Plasma A. Insulin
B. Platelets B. Starch
C. WBC C. Glycogen
D. RBC D. Cellulose

423. Plants lose water mainly through: 431. The energy currency of the cell is:
A. Root hairs A. DNA
B. Bark B. ATP
C. Stomata C. RNA
D. Cuticle D. NADPH

424. What is the function of bile in digestion? 432. Which of the following best describes
A. Digests carbohydrates autotrophic nutrition?
B. Digests proteins A. Intake of food from other organisms
C. Emulsifies fats B. Making food using sunlight
D. Absorbs vitamins C. Eating only plant-based food
D. Using nutrients from decayed matter
425. The contraction and relaxation of which
muscle helps in breathing? 433. What causes the "lub-dub" sound of the
A. Cardiac muscle heartbeat?
B. Diaphragm A. Opening of valves
C. Intercostal muscles B. Closing of valves
D. Both B and C C. Blood rushing through arteries
D. Contraction of ventricles
426. Blood is filtered in the kidneys by units called:
A. Neurons 434. The breakdown of food into simpler
B. Nephrons substances is called:
C. Nephridia A. Ingestion
D. Alveoli B. Digestion
C. Absorption
427. Which of the following contains oxygenated D. Assimilation
blood?
A. Pulmonary artery 435. Plants transport food from leaves to other
B. Right atrium parts through:
C. Pulmonary vein A. Xylem
D. Right ventricle B. Phloem
C. Chloroplast
428. (Critical Thinking) If all the stomata in a leaf D. Parenchyma
closed permanently, what would be the most
immediate effect? 436. Which part of the digestive system has villi?
A. Water uptake would increase A. Stomach
B. Photosynthesis would increase B. Large intestine
C. Transpiration would stop C. Small intestine
D. The plant would grow faster D. Esophagus

429. What is the role of the large intestine? 437. In humans, urea is formed in the:
A. Digests fats A. Kidney
B. Absorbs nutrients B. Liver
C. Heart C. Cerebellum
D. Lungs D. Hypothalamus

438. Which component of blood helps in clotting? 446. The structure that prevents food from entering
A. RBC the windpipe is:
B. WBC A. Pharynx
C. Platelets B. Larynx
D. Plasma C. Epiglottis
D. Esophagus
439. Which gas is used during aerobic respiration?
A. Carbon dioxide 447. In the human digestive system, digestion of
B. Oxygen carbohydrates starts in:
C. Nitrogen A. Stomach
D. Hydrogen B. Mouth
C. Small intestine
440. The root pressure responsible for upward D. Liver
movement of water is due to:
A. Active absorption 448. (Critical Thinking) If a plant receives water but
B. Transpiration no sunlight, what process will be most affected?
C. Passive transport A. Transpiration
D. Capillary action B. Respiration
C. Photosynthesis
441. (Analytical) Why are alveoli adapted for D. Germination
gaseous exchange?
A. They are small and thick-walled 449. The blood vessel that brings blood from the
B. They have high surface area and thin walls body to the heart is:
C. They are filled with blood A. Aorta
D. They are part of the heart B. Pulmonary vein
C. Pulmonary artery
442. Which type of respiration produces more D. Vena cava
energy?
A. Anaerobic 450. Which of the following does not belong to the
B. Fermentation excretory system?
C. Aerobic A. Kidney
D. None B. Ureter
C. Lungs
443. Which organ excretes carbon dioxide from the D. Urinary bladder
body?
A. Kidney 451. The main nitrogenous waste in humans is:
B. Lungs A. Uric acid
C. Skin B. Ammonia
D. Liver C. Urea
D. Creatinine
444. Which blood cells carry oxygen?
A. WBC 452. Which enzyme acts in the mouth during
B. RBC digestion?
C. Platelets A. Trypsin
D. Plasma B. Pepsin
C. Amylase
445. Which part of the brain controls involuntary D. Lipase
actions like breathing?
A. Cerebrum 453. What is the primary function of red blood
B. Medulla cells?
A. Transport carbon dioxide 461. Which of these is not a life process?
B. Fight infection A. Respiration
C. Clot blood B. Reproduction
D. Transport oxygen C. Photosynthesis
D. Crystallization
454. Which of these is a by-product of cellular
respiration? 462. Which of the following processes is not
A. Oxygen involved in the human digestive system?
B. Carbon dioxide A. Ingestion
C. Glucose B. Excretion
D. ATP C. Absorption
D. Assimilation
455. What is the main function of stomata?
A. Absorb minerals 463. The main site of protein digestion in humans
B. Absorb sunlight is:
C. Exchange gases A. Mouth
D. Conduct water B. Esophagus
C. Stomach
456. Which of the following helps in the D. Large intestine
emulsification of fats?
A. Trypsin 464. During aerobic respiration, the end products
B. HCl are:
C. Bile A. Lactic acid and energy
D. Lipase B. Ethanol and carbon dioxide
C. Carbon dioxide, water, and energy
457. Which part of the digestive system has acidic D. Glucose and oxygen
conditions?
A. Small intestine 465. Which organ filters blood to remove
B. Large intestine nitrogenous waste?
C. Stomach A. Heart
D. Esophagus B. Kidney
C. Liver
458. (Analytical) Which process would increase if a D. Lungs
person starts doing intense exercise?
A. Anaerobic respiration 466. The correct order of blood flow through the
B. Photosynthesis heart is:
C. Nitrogen fixation A. Atrium → Veins → Ventricles → Arteries
D. Filtration B. Veins → Ventricles → Atrium → Arteries
C. Veins → Atrium → Ventricles → Arteries
459. In which organ does absorption of digested D. Arteries → Atrium → Veins → Ventricles
food mainly take place?
A. Stomach 467. (Analytical) Which part of the nephron is
B. Large intestine directly responsible for selective reabsorption?
C. Small intestine A. Bowman's capsule
D. Liver B. Glomerulus
C. Loop of Henle
460. Which hormone helps in regulating the D. Proximal convoluted tubule
amount of glucose in the blood?
A. Insulin 468. Which of the following is not a function of
B. Adrenaline transpiration?
C. Thyroxine A. Helps in nutrient absorption
D. Estrogen B. Maintains temperature
C. Removes oxygen
D. Creates a suction pull 477. Blood circulation was discovered by:
A. Robert Hooke
469. The epiglottis prevents food from entering the: B. William Harvey
A. Stomach C. Alexander Fleming
B. Windpipe D. Watson and Crick
C. Food pipe
D. Nasal cavity 478. What is the function of guard cells?
A. Absorb water from roots
470. The wall of alveoli is: B. Protect xylem
A. Thick and dry C. Control opening and closing of stomata
B. Thin and moist D. Transport food
C. Thin and dry
D. Thick and moist 479. (Critical Thinking) Which change would directly
decrease the rate of transpiration in a plant?
471. The source of oxygen used in respiration is: A. Increasing wind speed
A. Carbon dioxide B. Decreasing humidity
B. Water C. Removing leaves
C. Atmosphere D. Increasing temperature
D. Glucose
480. The energy stored in food is in the form of:
472. The main role of ATP in cells is to: A. Oxygen
A. Store genetic information B. Chemical bonds
B. Provide structural support C. Nitrogen
C. Provide energy D. Water
D. Maintain cell shape
481. Which blood component carries nutrients,
473. The breakdown of glucose into pyruvate hormones, and waste?
occurs in the: A. RBC
A. Mitochondria B. Plasma
B. Cytoplasm C. WBC
C. Nucleus D. Platelets
D. Ribosome
482. Which is the correct path of air in the human
474. Which of the following processes is not respiratory system?
performed by the kidneys? A. Nasal cavity → Larynx → Trachea → Bronchi →
A. Filtration Lungs
B. Reabsorption B. Lungs → Bronchi → Trachea → Nasal cavity
C. Respiration C. Nasal cavity → Trachea → Larynx → Bronchi →
D. Secretion Lungs
D. Trachea → Nasal cavity → Lungs
475. Which enzyme is active in the stomach?
A. Amylase 483. The largest gland in the human body is:
B. Lipase A. Pancreas
C. Pepsin B. Thyroid
D. Trypsin C. Liver
D. Pituitary
476. What will happen if the valves in veins stop
functioning properly? 484. Water is mainly absorbed by plants through:
A. Oxygen will not bind to hemoglobin A. Roots
B. Blood will not clot B. Stems
C. Blood may flow backward C. Leaves
D. More RBCs will be produced D. Flowers
485. What connects arteries and veins in the
tissues? 493. In which part of the nephron does filtration
A. Alveoli occur?
B. Capillaries A. Loop of Henle
C. Ureters B. Glomerulus
D. Nephrons C. Collecting duct
D. Ureter
486. The end product of digestion of carbohydrates
is: 494. Translocation of food in plants occurs through:
A. Amino acids A. Xylem
B. Fatty acids B. Phloem
C. Glucose C. Cortex
D. Glycerol D. Root hairs

487. Which of the following is not a digestive 495. The ureter carries urine from:
enzyme? A. Bladder to urethra
A. Pepsin B. Kidney to bladder
B. Lipase C. Kidney to urethra
C. Amylase D. Liver to kidney
D. Hemoglobin
496. (Critical Thinking) A student boiled a leaf in
488. (Analytical) A person is breathing heavily after alcohol and then added iodine. The leaf turned
running. This is because: blue-black. This indicates:
A. The brain is tired A. Protein is present
B. Lungs are dry B. Fat is present
C. Muscles need more oxygen to produce energy C. Starch is present
D. Bones are weak D. Water is present

489. The breakdown of fat is assisted by: 497. Which enzyme digests proteins in the small
A. Bile intestine?
B. Amylase A. Amylase
C. Trypsin B. Pepsin
D. Pepsin C. Trypsin
D. Lipase
490. The blood vessel that carries oxygen-rich blood
from lungs to heart is: 498. The lungs are enclosed in a cavity called:
A. Pulmonary artery A. Pericardium
B. Pulmonary vein B. Pleural cavity
C. Vena cava C. Bronchus
D. Aorta D. Alveoli

491. Which of the following is a part of the 499. Anaerobic respiration in yeast produces:
excretory system in humans? A. Lactic acid
A. Bronchi B. Ethanol and CO₂
B. Nephron C. Glucose and ATP
C. Phloem D. Urea and water
D. Capillary
500. Which structure prevents the backflow of
492. In photosynthesis, the gas released is: blood in veins?
A. CO₂ A. Muscles
B. O₂ B. Capillaries
C. H₂ C. Valves
D. N₂ D. RBCs
501. The main function of the Loop of Henle in the 509. The enzyme lipase acts on:
nephron is: A. Fats
A. Filtration B. Proteins
B. Reabsorption of water C. Sugars
C. Urine formation D. Vitamins
D. Breakdown of glucose
510. Which part of the nephron collects the filtrate
502. In respiration, the release of energy occurs in after it passes through the tubules?
the form of: A. Glomerulus
A. Heat B. Bowman's capsule
B. Light C. Collecting duct
C. ATP D. Loop of Henle
D. Water
511. The blood vessel that carries blood from the
503. Which organ plays a major role in heart to the body is:
detoxification? A. Pulmonary vein
A. Kidney B. Vena cava
B. Liver C. Aorta
C. Lungs D. Renal vein
D. Heart
512. In human beings, the blood leaving the lungs is
504. Which of these has a double circulation rich in:
system? A. Carbon dioxide
A. Amoeba B. Nitrogen
B. Earthworm C. Oxygen
C. Human D. Urea
D. Hydra
513. Which organ is responsible for the production
505. The primary function of platelets is: of bile?
A. Transport oxygen A. Stomach
B. Blood clotting B. Liver
C. Immune response C. Pancreas
D. Hormone transport D. Gall bladder

506. In plants, the xylem transports: 514. The function of bile in digestion is to:
A. Food A. Digest starch
B. Hormones B. Emulsify fats
C. Water and minerals C. Digest proteins
D. Oxygen D. Break down glucose

507. (Analytical) If the stomata are closed for a long 515. The walls of the small intestine have
time, which process is most likely to slow down? numerous finger-like projections called:
A. Protein synthesis A. Cilia
B. Water absorption B. Villi
C. Photosynthesis C. Microtubules
D. Translocation D. Alveoli

508. The main respiratory organ in humans is: 516. Which chamber of the heart receives
A. Trachea oxygenated blood from the lungs?
B. Larynx A. Left ventricle
C. Alveoli B. Right atrium
D. Lungs C. Right ventricle
D. Left atrium D. Carotene

517. Blood pressure is measured using an 525. The human urinary system does not include:
instrument called: A. Urethra
A. Thermometer B. Kidney
B. Sphygmomanometer C. Ureter
C. Stethoscope D. Liver
D. Barometer
526. Which blood cells help in immunity?
518. (Critical Thinking) Which will happen if alveoli A. Red blood cells
are filled with fluid? B. White blood cells
A. Gas exchange will improve C. Platelets
B. Breathing rate will decrease D. Plasma
C. Gas exchange will reduce
D. Lungs will expand more 527. The pulmonary artery carries:
A. Oxygen-rich blood to the lungs
519. The enzyme amylase breaks down: B. Oxygen-rich blood from lungs
A. Proteins C. Oxygen-poor blood to lungs
B. Fats D. Oxygen-poor blood from lungs
C. Carbohydrates
D. Nucleic acids 528. Which part of the nephron is cup-shaped and
surrounds the glomerulus?
520. In plants, water moves primarily through: A. Loop of Henle
A. Phloem B. Proximal tubule
B. Xylem C. Bowman's capsule
C. Cortex D. Collecting duct
D. Stomata
529. Food is pushed down the esophagus by a
521. Which part of the plant loses water during process called:
transpiration? A. Swallowing
A. Root hairs B. Peristalsis
B. Vessels C. Emulsification
C. Stomata D. Diffusion
D. Phloem
530. In humans, urea is formed in the:
522. Anaerobic respiration does not use: A. Kidney
A. Water B. Liver
B. Glucose C. Heart
C. Oxygen D. Intestine
D. Enzymes
531. The final site of digestion and absorption of
523. The process of removal of metabolic wastes in nutrients is:
humans is called: A. Large intestine
A. Secretion B. Stomach
B. Digestion C. Esophagus
C. Excretion D. Small intestine
D. Assimilation
532. Blood is prevented from flowing backward in
524. The pigment that traps light in photosynthesis the heart by:
is: A. Valves
A. Hemoglobin B. Capillaries
B. Melanin C. Arteries
C. Chlorophyll D. Veins
533. Which of the following is a function of 541. Water enters root hairs by the process of:
phloem? A. Diffusion
A. Transport of water B. Transpiration
B. Transport of oxygen C. Osmosis
C. Transport of food D. Active transport
D. Transport of nitrogen
542. Which of the following is not an excretory
534. Which part of the brain controls the rate of product?
breathing? A. Carbon dioxide
A. Cerebrum B. Urea
B. Medulla oblongata C. Oxygen
C. Cerebellum D. Sweat
D. Pons
543. Fatty acids and glycerol are absorbed in the:
535. The process of photosynthesis is most active A. Stomach
in: B. Large intestine
A. Roots C. Small intestine
B. Stems D. Esophagus
C. Leaves
D. Flowers 544. A student places a plant in a closed jar. After
some time, oxygen level decreases. Why?
536. In double circulation, blood passes through the A. Photosynthesis increases
heart: B. Transpiration stops
A. Once C. Respiration continues
B. Twice D. Water evaporates
C. Three times
D. Not at all 545. What is the role of stomata in plants?
A. Photosynthesis
537. Which component of blood helps in clotting? B. Transport of food
A. RBCs C. Gaseous exchange
B. WBCs D. Absorption of minerals
C. Platelets
D. Plasma 546. During anaerobic respiration in human
muscles, the end product is:
538. (Analytical) Why do athletes take deep breaths A. Alcohol
after running? B. Carbon dioxide
A. To increase heartbeat C. Lactic acid
B. To cool down D. Oxygen
C. To remove lactic acid
D. To store oxygen in muscles 547. In fish, gas exchange occurs through:
A. Lungs
539. Aorta is a: B. Gills
A. Vein that brings blood to heart C. Skin
B. Vein that carries blood from lungs D. Air sacs
C. Artery that carries oxygenated blood to body
D. Artery that brings blood to lungs 548. Which part of the digestive system is
responsible for digestion and absorption both?
540. The site of aerobic respiration in cells is: A. Mouth
A. Cytoplasm B. Stomach
B. Mitochondria C. Small intestine
C. Ribosomes D. Large intestine
D. Nucleus
549. The loss of water through stomata is called: human body?
A. Translocation A. Kidney → Ureter → Bladder → Urethra
B. Respiration B. Ureter → Kidney → Bladder → Urethra
C. Transpiration C. Kidney → Bladder → Ureter → Urethra
D. Photosynthesis D. Bladder → Urethra → Kidney → Ureter

550. In what form are carbohydrates stored in 558. What gives red color to blood?
humans? A. Plasma
A. Glucose B. Chlorophyll
B. Cellulose C. Hemoglobin
C. Glycogen D. Iron
D. Starch
559. Which of these life processes occurs in plants
551. What does the term "life processes" include? only during the day?
A. Respiration and excretion A. Respiration
B. Nutrition B. Photosynthesis
C. Transportation C. Translocation
D. All of the above D. Water absorption

552. Which of these is not required for 560. Which blood vessel carries blood from body to
photosynthesis? heart?
A. Light A. Aorta
B. Oxygen B. Pulmonary vein
C. Water C. Vena cava
D. Carbon dioxide D. Pulmonary artery

553. Which part of the plant is responsible for 561. In animals, the oxygen required for respiration
absorption of water? is transported by:
A. Leaves A. Plasma
B. Stem B. Platelets
C. Root hairs C. Hemoglobin
D. Flowers D. WBC

554. Which blood vessels have thin walls and allow 562. The fluid part of blood is known as:
exchange of substances? A. Platelets
A. Arteries B. Plasma
B. Veins C. RBC
C. Capillaries D. WBC
D. Lymph vessels
563. What is the primary function of red blood
555. In amoeba, food is ingested by: cells?
A. Cilia A. Fight infection
B. Tentacles B. Help in clotting
C. Pseudopodia C. Transport oxygen
D. Flagella D. Digest bacteria

556. The pharynx is part of both: 564. The movement of food through the alimentary
A. Digestive and circulatory system canal is due to:
B. Respiratory and circulatory system A. Cilia
C. Digestive and respiratory system B. Peristalsis
D. Nervous and respiratory system C. Diffusion
D. Gravity
557. Which is the correct pathway of urine in the
565. Which component of food starts digestion in 573. In which part of the nephron does filtration
the mouth? occur?
A. Proteins A. Loop of Henle
B. Fats B. Collecting duct
C. Starch C. Bowman's capsule
D. Cellulose D. Proximal tubule

566. The digestion of protein starts in the: 574. In which form is excess glucose stored in
A. Mouth human body?
B. Small intestine A. Starch
C. Stomach B. Glycogen
D. Large intestine C. Glucose
D. Fatty acids
567. Which blood vessels carry blood away from
the heart? 575. Which part of the brain controls excretion and
A. Veins respiration?
B. Capillaries A. Cerebrum
C. Arteries B. Cerebellum
D. Lymph vessels C. Medulla oblongata
D. Pons
568. (Analytical) In a plant kept in the dark, which
process stops first? 576. Which blood cells help in clotting?
A. Respiration A. RBCs
B. Transpiration B. WBCs
C. Photosynthesis C. Platelets
D. Absorption D. Plasma

569. Which of these is a waste product of 577. (Critical Thinking) Why do leaves appear
photosynthesis? wilted when plant lacks water?
A. Carbon dioxide A. Photosynthesis increases
B. Oxygen B. No transpiration
C. Water C. Turgor pressure decreases
D. Glucose D. Nutrients lost

570. Excretory unit of kidney is called: 578. Which enzyme acts in the stomach to digest
A. Neuron proteins?
B. Alveolus A. Trypsin
C. Nephron B. Amylase
D. Glomerulus C. Pepsin
D. Lipase
571. In aerobic respiration, the end products are:
A. Alcohol and CO₂ 579. Which vessels have valves?
B. Lactic acid and CO₂ A. Arteries
C. Glucose and oxygen B. Veins
D. CO₂, water, and energy C. Capillaries
D. Arterioles
572. Which part of the alimentary canal receives
bile? 580. Urine is stored in which organ?
A. Mouth A. Ureter
B. Esophagus B. Kidney
C. Stomach C. Urethra
D. Small intestine D. Urinary bladder
581. Lungs are surrounded by a protective covering 589. What does the pancreas secrete?
called: A. Bile
A. Pericardium B. Insulin and enzymes
B. Pleura C. Glucagon only
C. Diaphragm D. Amylase only
D. Bronchi
590. The tiny air sacs in the lungs where gas
582. Which blood vessel carries oxygenated blood exchange occurs are called:
from lungs to heart? A. Bronchioles
A. Pulmonary artery B. Trachea
B. Pulmonary vein C. Alveoli
C. Aorta D. Bronchi
D. Vena cava
591. In which form do plants absorb nitrogen?
583. Which of the following is NOT a function of the A. Urea
liver? B. Proteins
A. Bile secretion C. Nitrates and nitrites
B. Urea formation D. Atmospheric nitrogen directly
C. Food digestion
D. Blood detoxification 592. The flap that covers the trachea during
swallowing is:
584. The function of guard cells is to: A. Pharynx
A. Absorb water B. Larynx
B. Close and open stomata C. Epiglottis
C. Transport food D. Bronchus
D. Support leaves
593. Which cells contain hemoglobin?
585. Which structure prevents food from entering A. White blood cells
the windpipe? B. Platelets
A. Diaphragm C. Red blood cells
B. Pharynx D. Plasma cells
C. Epiglottis
D. Esophagus 594. Which of the following is the longest part of
the alimentary canal?
586. Carbon dioxide is transported in blood mainly A. Esophagus
in the form of: B. Large intestine
A. Free CO₂ gas C. Small intestine
B. Dissolved gas D. Stomach
C. Carbamino compounds
D. Bicarbonate ions 595. What is the function of the loop of Henle?
A. Filtration
587. Which process uses solar energy? B. Reabsorption
A. Respiration C. Secretion
B. Photosynthesis D. Blood transport
C. Transpiration
D. Excretion 596. The waste excreted by lungs is:
A. Water
588. Which blood vessel supplies blood to kidneys? B. Urea
A. Renal artery C. Salts
B. Renal vein D. Carbon dioxide
C. Hepatic vein
D. Pulmonary artery 597. (Analytical) Why does the heart have four
chambers?
A. To slow down blood flow 605. Name the pigment present in RBCs:
B. For separation of oxygenated and deoxygenated A. Chlorophyll
blood B. Melanin
C. To reduce blood pressure C. Hemoglobin
D. To reduce heart size D. Carotene

598. What structure helps in oxygen transport in 606. Which gas is essential for aerobic respiration?
humans? A. Oxygen
A. Plasma B. Carbon dioxide
B. Hemoglobin C. Nitrogen
C. Platelets D. Hydrogen
D. WBC
607. What is the main function of the large
599. The enzyme lipase breaks down: intestine?
A. Proteins A. Digestion
B. Fats B. Absorption of water
C. Starch C. Protein breakdown
D. Glucose D. Starch digestion

600. The amount of air left in lungs after expiration 608. Which plant organ loses the most water
is: through transpiration?
A. Tidal volume A. Roots
B. Residual volume B. Stem
C. Expiratory reserve C. Leaves
D. Vital capacity D. Flowers

601. Which of the following is absorbed by villi in 609. Blood entering the kidney is:
the small intestine? A. Oxygen-poor
A. Oxygen B. Nitrogen-poor
B. Amino acids C. Unfiltered
C. Carbon dioxide D. Deoxygenated and filtered
D. Urea
610. The part of nephron where most reabsorption
602. Which organ removes nitrogenous wastes occurs:
from the blood? A. Glomerulus
A. Liver B. Collecting duct
B. Lungs C. Loop of Henle
C. Kidneys D. Proximal convoluted tubule
D. Skin
611. The opening and closing of stomata is
603. (Critical Thinking) What will happen if stomata controlled by:
remain closed all day? A. Light
A. Transpiration increases B. Temperature
B. Photosynthesis decreases C. Guard cells
C. Water absorption increases D. Wind
D. Glucose formation increases
612. The blood vessel that brings oxygen-rich blood
604. In plants, the food is transported through: from the lungs to the heart is:
A. Xylem A. Pulmonary artery
B. Phloem B. Aorta
C. Root hairs C. Pulmonary vein
D. Guard cells D. Vena cava
613. The energy currency of the cell is: 621. Villi increase the surface area for:
A. DNA A. Digestion
B. Glucose B. Secretion
C. ATP C. Absorption
D. RNA D. Filtration

614. Which of the following is not a digestive 622. The structural and functional unit of lungs is:
enzyme? A. Bronchi
A. Pepsin B. Bronchioles
B. Amylase C. Alveoli
C. Insulin D. Trachea
D. Trypsin
623. Which is the largest artery in the human body?
615. Which excretory product is removed by the A. Pulmonary artery
skin? B. Aorta
A. Carbon dioxide C. Vena cava
B. Urea D. Coronary artery
C. Salts and water
D. Glucose 624. The human respiratory system starts with:
A. Bronchi
616. What prevents the backflow of blood in veins? B. Lungs
A. Thick walls C. Nasal cavity
B. Valves D. Trachea
C. Muscles
D. RBCs 625. The lungs are located in which cavity?
A. Abdominal
617. Which of these is a vestigial organ in humans? B. Thoracic
A. Kidney C. Pelvic
B. Appendix D. Cranial
C. Liver
D. Heart 626. Which part of the nephron collects urine?
A. Loop of Henle
618. (Critical Thinking) During heavy exercise, B. Glomerulus
muscles produce lactic acid because: C. Collecting duct
A. Aerobic respiration speeds up D. Bowman's capsule
B. Oxygen is in excess
C. Anaerobic respiration occurs 627. The waste product of protein metabolism is:
D. ATP is not required A. Salt
B. Urea
619. Which process is responsible for water C. Glucose
movement in xylem? D. Bile
A. Translocation
B. Transpiration pull 628. (Analytical) Which part of the plant has both
C. Osmosis xylem and phloem?
D. Diffusion A. Root only
B. Leaf only
620. Which of these organs does not have a role in C. Stem only
excretion? D. All of these
A. Skin
B. Lungs 629. The rate of transpiration is higher on:
C. Heart A. Humid day
D. Kidney B. Windy day
C. Cloudy day
D. Cold day 638. Which blood vessels form a network around
the nephrons?
630. Which pigment absorbs light for A. Arteries
photosynthesis? B. Capillaries
A. Hemoglobin C. Veins
B. Melanin D. Venules
C. Chlorophyll
D. Keratin 639. (Critical Thinking) Why does glucose not
appear in urine of healthy people?
631. Which organ filters blood to form urine? A. It is not filtered at all
A. Heart B. It is reabsorbed completely
B. Liver C. It is converted to protein
C. Kidney D. It is broken into amino acids
D. Lungs
640. Which structure helps to equalize air pressure
632. The muscular wall that separates the chest on both sides of the eardrum?
and abdominal cavities is: A. Cochlea
A. Diaphragm B. Eustachian tube
B. Epiglottis C. Tympanic membrane
C. Trachea D. Semi-circular canal
D. Sternum
641. Which is the correct sequence in the human
633. Blood leaving the lungs is rich in: digestive system?
A. Carbon dioxide A. Mouth → Esophagus → Stomach → Small
B. Urea intestine → Large intestine
C. Oxygen B. Mouth → Stomach → Esophagus → Small
D. Ammonia intestine → Large intestine
C. Mouth → Small intestine → Esophagus →
634. The enzyme secreted by the salivary glands is: Stomach → Large intestine
A. Pepsin D. Mouth → Large intestine → Esophagus →
B. Amylase Stomach → Small intestine
C. Lipase
D. Trypsin 642. Which of these is a double circulation organ?
A. Kidney
635. Which organ stores bile? B. Heart
A. Liver C. Lungs
B. Gallbladder D. Liver
C. Pancreas
D. Stomach 643. Blood in arteries is under:
A. No pressure
636. The tube that connects the kidney to the B. Negative pressure
bladder is called: C. High pressure
A. Urethra D. Low pressure
B. Ureter
C. Nephron 644. The glomerulus is a part of:
D. Alveolus A. Alveolus
B. Nephron
637. In plants, excess water is removed by: C. Capillary
A. Guttation D. Heart
B. Transpiration
C. Evaporation 645. What part of the blood helps in immune
D. Osmosis response?
A. Plasma
B. Platelets 653. (Critical Thinking) Why do plants close stomata
C. WBCs during night?
D. RBCs A. For photosynthesis
B. To stop CO₂ intake
646. The hormone that regulates sugar level in C. To prevent water loss
blood is: D. To increase transpiration
A. Pepsin
B. Insulin 654. The large intestine mainly absorbs:
C. Glucagon A. Glucose
D. Trypsin B. Proteins
C. Water
647. Photosynthesis takes place in which part of D. Fats
the plant cell?
A. Nucleus 655. Which part of the respiratory system contains
B. Chloroplast vocal cords?
C. Ribosome A. Larynx
D. Mitochondria B. Pharynx
C. Trachea
648. In anaerobic respiration, how many ATP D. Bronchus
molecules are produced per glucose?
A. 36 656. In which direction does oxygen diffuse in
B. 2 alveoli?
C. 4 A. Blood → alveoli
D. 0 B. Alveoli → blood
C. Lungs → nose
649. Name the structure that connects the pharynx D. Heart → lungs
to the stomach:
A. Larynx 657. The function of the peristaltic movement is to:
B. Epiglottis A. Absorb nutrients
C. Esophagus B. Eliminate waste
D. Trachea C. Move food forward
D. Produce saliva
650. Which of these carries blood from the heart to
all body parts? 658. Fat digestion occurs mostly in:
A. Vena cava A. Mouth
B. Aorta B. Stomach
C. Pulmonary artery C. Large intestine
D. Renal vein D. Small intestine

651. The final stage of digestion and nutrient 659. Which organ excretes carbon dioxide?
absorption occurs in: A. Liver
A. Large intestine B. Skin
B. Small intestine C. Lungs
C. Stomach D. Kidneys
D. Mouth
660. Which structure prevents entry of food into
652. (Analytical) What would happen if blood windpipe?
lacked platelets? A. Esophagus
A. Oxygen transport stops B. Larynx
B. No immune defense C. Epiglottis
C. Bleeding will not stop D. Uvula
D. Blood sugar increases
661. Which part of the digestive system absorbs
digested food? A. Autotrophic
A. Stomach B. Parasitic
B. Large intestine C. Holozoic
C. Small intestine D. Saprophytic
D. Esophagus
670. In plants, food is transported from leaves to
662. Which of the following is a function of bile? storage organs via:
A. Digests carbohydrates A. Xylem
B. Digests proteins B. Phloem
C. Emulsifies fats C. Cambium
D. Neutralizes acid in the mouth D. Vessels

663. Which chamber of the heart receives oxygen- 671. Which of the following substances is not
rich blood from lungs? excreted by human kidneys?
A. Right atrium A. Urea
B. Left atrium B. Glucose
C. Right ventricle C. Water
D. Left ventricle D. Salts

664. Which enzyme is present in pancreatic juice? 672. (Critical Thinking) What would happen if the
A. Amylase pancreas did not function?
B. Pepsin A. No bile secretion
C. Lipase B. Improper fat digestion
D. Both A and C C. Improper protein and carbohydrate digestion
D. Both B and C
665. The longest part of the alimentary canal is:
A. Large intestine 673. During inhalation, diaphragm:
B. Small intestine A. Relaxes and moves up
C. Stomach B. Contracts and moves down
D. Esophagus C. Expands and moves up
D. Contracts and moves up
666. Which blood vessels have thick muscular
walls? 674. The capillaries surrounding alveoli are
A. Arteries connected to:
B. Veins A. Pulmonary artery and vein
C. Capillaries B. Aorta and vena cava
D. Venules C. Heart chambers
D. Trachea and bronchi
667. (Analytical) Why are alveoli well-suited for gas
exchange? 675. Which blood component helps in clotting?
A. Thin walls A. WBC
B. Large surface area B. RBC
C. Moist lining C. Platelets
D. All of the above D. Plasma

668. The removal of metabolic wastes from the 676. The end products of aerobic respiration are:
body is called: A. Glucose and oxygen
A. Nutrition B. Glucose and ATP
B. Excretion C. Carbon dioxide and water
C. Respiration D. Alcohol and carbon dioxide
D. Digestion
677. In which part of the nephron does filtration of
669. In amoeba, nutrition is: blood occur?
A. Loop of Henle 685. In aerobic respiration, the majority of ATP is
B. Collecting duct produced in:
C. Glomerulus A. Cytoplasm
D. Proximal tubule B. Nucleus
C. Mitochondria
678. The mode of nutrition in fungi is: D. Ribosome
A. Autotrophic
B. Holozoic 686. Ureters carry urine from:
C. Parasitic A. Urethra to bladder
D. Saprophytic B. Kidneys to bladder
C. Bladder to urethra
679. Which part of the plant mainly performs D. Bladder to kidneys
transpiration?
A. Stem 687. The site of photosynthesis in a plant cell is:
B. Root A. Chloroplast
C. Stomata B. Mitochondria
D. Flowers C. Ribosome
D. Vacuole
680. Which of the following is absorbed by the
large intestine? 688. Which pigment traps sunlight in
A. Amino acids photosynthesis?
B. Glucose A. Carotene
C. Water B. Xanthophyll
D. Fatty acids C. Chlorophyll
D. Hemoglobin
681. In the human heart, which chamber pumps
blood into the aorta? 689. Which of these does not play a direct role in
A. Right atrium digestion?
B. Left atrium A. Stomach
C. Right ventricle B. Pancreas
D. Left ventricle C. Gallbladder
D. Lungs
682. Which of the following is not a function of the
liver? 690. (Critical Thinking) If xylem gets blocked, the
A. Production of bile plant will face difficulty in:
B. Storage of glucose A. Food transport
C. Detoxification B. Water transport
D. Filtration of urea C. Photosynthesis
D. Seed germination
683. Which organ in humans performs both
digestion and absorption? 691. Which structure in the human body helps filter
A. Liver nitrogenous waste?
B. Stomach A. Liver
C. Small intestine B. Lungs
D. Large intestine C. Kidney
D. Heart
684. (Analytical) Why does blood in the pulmonary
artery have low oxygen? 692. Which plant tissue is responsible for
A. It comes from the heart transporting food?
B. It has passed through the lungs A. Parenchyma
C. It is returning from the body B. Xylem
D. It is going to the lungs for oxygenation C. Collenchyma
D. Phloem
 A. Liver
693. Which gas is released during photosynthesis? B. Mouth
A. Carbon dioxide C. Stomach
B. Nitrogen D. Pancreas
C. Oxygen
D. Hydrogen 702. (Analytical) In case of diarrhea, why is oral
rehydration solution (ORS) given?
694. Which of the following is NOT a product of A. Provides oxygen
digestion? B. Supplies salts and water
A. Amino acids C. Kills bacteria
B. Glucose D. Helps digestion
C. Fatty acids
D. DNA 703. In humans, how many kidneys are present?
A. 1
695. Pulmonary vein carries: B. 2
A. Deoxygenated blood C. 3
B. Oxygenated blood D. 4
C. Lymph
D. Wastes 704. In plants, transpiration helps in:
A. Protein formation
696. Which blood cells carry oxygen? B. Oxygen release
A. WBC C. Mineral transport
B. Platelets D. Reproduction
C. Plasma
D. RBC 705. Which plant structure opens and closes the
stomata?
697. Which substance is mainly reabsorbed in the A. Root hairs
nephron? B. Guard cells
A. Urea C. Xylem
B. Glucose D. Phloem
C. Hemoglobin
D. Creatinine 706. The process of breakdown of food in cells to
release energy is called:
698. Anaerobic respiration in yeast produces: A. Digestion
A. Lactic acid B. Respiration
B. Oxygen C. Excretion
C. Alcohol and CO₂ D. Photosynthesis
D. Glucose
707. What is the main waste product of respiration
699. The walls of capillaries are: in humans?
A. Thick and muscular A. Oxygen
B. Thick with valves B. Glucose
C. One-cell thick C. Carbon dioxide
D. None of these D. Alcohol

700. In plants, photosynthesis mainly occurs in: 708. Plants store food in the form of:
A. Roots A. Glucose
B. Leaves B. Glycogen
C. Flowers C. Starch
D. Fruits D. Protein

701. Which part of the digestive system contains 709. The trachea connects the:
hydrochloric acid? A. Mouth to stomach
B. Nose to lungs D. Collecting duct
C. Heart to lungs
D. Kidney to bladder 718. (Analytical) Why do arteries have thick walls?
A. To allow faster blood flow
710. Which organ removes carbon dioxide from B. To prevent mixing of blood
blood? C. To withstand high pressure
A. Kidney D. To allow oxygen diffusion
B. Skin
C. Liver 719. The main function of white blood cells is to:
D. Lungs A. Transport oxygen
B. Clot blood
711. The food pipe in humans is called: C. Fight infection
A. Trachea D. Carry nutrients
B. Esophagus
C. Larynx 720. Which process in plants depends directly on
D. Pharynx light?
A. Respiration
712. The valve between the left atrium and left B. Transpiration
ventricle is called: C. Photosynthesis
A. Tricuspid valve D. Absorption
B. Pulmonary valve
C. Bicuspid (mitral) valve 721. Which gas is absorbed by blood in the lungs?
D. Aortic valve A. Nitrogen
B. Oxygen
713. The epiglottis prevents food from entering the: C. Carbon dioxide
A. Stomach D. Hydrogen
B. Esophagus
C. Windpipe (trachea) 722. The structure where exchange of gases occurs
D. Mouth in lungs:
A. Bronchi
714. Which organ produces insulin? B. Trachea
A. Liver C. Alveoli
B. Stomach D. Diaphragm
C. Pancreas
D. Intestine 723. The basic unit of the kidney is called:
A. Neuron
715. Urea is produced in: B. Nephron
A. Kidneys C. Alveolus
B. Liver D. Glomerulus
C. Lungs
D. Skin 724. Which of the following has autotrophic
nutrition?
716. Blood is filtered in the kidneys by: A. Human
A. Alveoli B. Amoeba
B. Nephrons C. Paramecium
C. Neurons D. Green plant
D. Villi
725. The process by which green plants make food
717. Which part of the nephron collects the filtered is:
urine? A. Transpiration
A. Bowman’s capsule B. Respiration
B. Loop of Henle C. Photosynthesis
C. Glomerulus D. Excretion
 D. Absorption
726. Which of the following is not involved in
human respiration? 734. Glucose is converted into energy in:
A. Trachea A. Ribosome
B. Lungs B. Nucleus
C. Diaphragm C. Mitochondria
D. Esophagus D. Golgi body

727. The contraction and relaxation of muscles 735. Carbon dioxide is removed from the body
during breathing is controlled by: through:
A. Lungs A. Liver
B. Heart B. Lungs
C. Diaphragm C. Skin
D. Alveoli D. Intestines

728. Water is absorbed by root hairs through: 736. Which type of respiration does not require
A. Active transport oxygen?
B. Diffusion A. Aerobic
C. Osmosis B. Anaerobic
D. Evaporation C. External
D. Internal
729. The human heart is divided into:
A. 2 chambers 737. The vein that brings deoxygenated blood from
B. 3 chambers body to heart is:
C. 4 chambers A. Pulmonary vein
D. 5 chambers B. Hepatic vein
C. Vena cava
730. The pigment responsible for giving blood its D. Aorta
red color is:
A. Myoglobin 738. (Analytical) Which feature of alveoli helps
B. Hemoglobin increase efficiency of gas exchange?
C. Melanin A. Thick walls
D. Chlorophyll B. Small surface area
C. Moist walls
731. Which vessel brings oxygenated blood from D. Dry surface
lungs to heart?
A. Pulmonary artery 739. The blood vessel that carries blood from the
B. Pulmonary vein heart to lungs is:
C. Aorta A. Aorta
D. Vena cava B. Pulmonary artery
C. Vena cava
732. (Critical Thinking) What would happen if the D. Pulmonary vein
valves in veins stopped working?
A. Blood would not be oxygenated 740. The part of the small intestine where most
B. Blood would flow backward digestion occurs:
C. Blood pressure would increase in arteries A. Duodenum
D. No blood would flow to brain B. Ileum
C. Colon
733. The process of losing water through leaves is D. Rectum
called:
A. Evaporation 741. Which hormone helps regulate blood sugar
B. Transpiration levels?
C. Respiration A. Insulin
B. Adrenaline B. Liver
C. Thyroxine C. Pancreas
D. Glucagon D. Lung

742. Plants lose excess water in the form of: 750. What is the energy currency of the cell?
A. Droplets A. DNA
B. Water vapor B. ATP
C. Liquid C. RNA
D. Ice D. Glucose

743. Guard cells regulate the opening and closing 751. The enzyme that breaks down proteins in the
of: stomach is:
A. Xylem A. Pepsin
B. Phloem B. Trypsin
C. Stomata C. Amylase
D. Chloroplast D. Lipase

744. Photosynthesis takes place in which plant cell 752. The liver converts excess amino acids into:
organelle? A. Uric acid
A. Mitochondria B. Glucose
B. Golgi body C. Urea
C. Chloroplast D. Ammonia
D. Endoplasmic reticulum
753. In animals, the process of removing waste
745. Which organ in the human body is responsible products is called:
for reabsorbing water from undigested food? A. Excretion
A. Small intestine B. Digestion
B. Pancreas C. Respiration
C. Large intestine D. Circulation
D. Liver
754. Which part of the body is responsible for the
746. During photosynthesis, the plant uses carbon production of bile?
dioxide from: A. Stomach
A. Soil B. Pancreas
B. Water C. Liver
C. Atmosphere D. Gallbladder
D. Chloroplast
755. Which of these is NOT a part of the human
747. Which component of blood fights infection? digestive system?
A. RBC A. Esophagus
B. WBC B. Stomach
C. Platelets C. Lungs
D. Plasma D. Intestine

748. The tube connecting kidney to bladder is: 756. Which component of blood helps transport
A. Urethra nutrients and hormones?
B. Ureter A. Plasma
C. Nephron B. Platelets
D. Loop of Henle C. WBC
D. Hemoglobin
749. The presence of sugar in urine indicates a
problem with which organ? 757. In a plant, food prepared by photosynthesis is
A. Heart transported to other parts by:
A. Phloem A. Lipase
B. Xylem B. Amylase
C. Root hairs C. Trypsin
D. Guard cells D. Pepsin

758. The gas used during photosynthesis is: 766. Which part of the nephron filters blood?
A. Oxygen A. Loop of Henle
B. Nitrogen B. Bowman’s capsule
C. Carbon dioxide C. Collecting duct
D. Methane D. Renal pelvis

759. Which plant organ performs most 767. The movement of food through the digestive
photosynthesis? tract is called:
A. Root A. Digestion
B. Leaf B. Absorption
C. Stem C. Ingestion
D. Flower D. Peristalsis

760. (Critical Thinking) Which condition would 768. (Critical Thinking) A person has yellowing of
reduce photosynthesis in a plant? the eyes and dark urine. Which organ is likely
A. Abundant CO₂ affected?
B. High light intensity A. Stomach
C. Lack of chlorophyll B. Heart
D. Sufficient water C. Liver
D. Lung
761. In which form is energy stored in muscles?
A. Glucose 769. Which part of the small intestine is primarily
B. Glycogen responsible for nutrient absorption?
C. Protein A. Duodenum
D. ATP B. Ileum
C. Colon
762. In which part of the human body is bile D. Rectum
stored?
A. Liver 770. The vein carrying oxygen-rich blood is:
B. Pancreas A. Pulmonary artery
C. Stomach B. Pulmonary vein
D. Gallbladder C. Aorta
D. Vena cava
763. Which of the following is not an excretory
organ in humans? 771. Which of the following is the waste product of
A. Kidney aerobic respiration?
B. Lungs A. Alcohol
C. Skin B. CO₂
D. Pancreas C. Lactic acid
D. Ammonia
764. Which component of blood transports oxygen?
A. WBC 772. The presence of lactic acid in muscles is a sign
B. Platelets of:
C. Plasma A. Proper digestion
D. RBC B. Aerobic respiration
C. Anaerobic respiration
765. The enzyme that breaks down starch into D. Excretion
sugar is:
773. The mineral essential for hemoglobin is: B. Vena cava
A. Calcium C. Aorta
B. Magnesium D. Hepatic vein
C. Iron
D. Potassium 782. Which waste is removed through sweat
glands?
774. The tube which carries urine from the bladder A. Urea and salt
to outside the body is: B. Carbon dioxide
A. Ureter C. Ammonia
B. Urethra D. Water only
C. Nephron
D. Loop of Henle 783. The removal of metabolic wastes from the
body is called:
775. The functional unit of the lungs is: A. Respiration
A. Bronchi B. Nutrition
B. Bronchioles C. Excretion
C. Alveoli D. Digestion
D. Trachea
784. The breakdown of glucose in absence of
776. Transpiration helps in: oxygen is called:
A. Absorption of food A. Combustion
B. Circulation of blood B. Aerobic respiration
C. Removal of waste gases C. Anaerobic respiration
D. Cooling of plant D. Glycolysis

777. (Analytical) Why does stomata close at night? 785. Which part of the digestive system is involved
A. To conserve oxygen in absorption of water?
B. To stop photosynthesis A. Stomach
C. To reduce water loss B. Small intestine
D. To allow respiration C. Large intestine
D. Esophagus
778. The part of blood involved in clotting is:
A. RBC 786. The kidneys are located in which cavity of the
B. WBC body?
C. Platelets A. Thoracic
D. Plasma B. Cranial
C. Abdominal
779. Which structure in plants transports water? D. Pelvic
A. Xylem
B. Phloem 787. The blood vessel that brings oxygen-poor
C. Stomata blood to the lungs is:
D. Chloroplast A. Pulmonary vein
B. Pulmonary artery
780. The green pigment in plants that absorbs C. Aorta
sunlight is: D. Vena cava
A. Xanthophyll
B. Carotene 788. The function of peristalsis is:
C. Chlorophyll A. Gas exchange
D. Hemoglobin B. Digestive enzyme production
C. Movement of food
781. Which blood vessel carries blood from heart to D. Blood circulation
body parts?
A. Pulmonary vein 789. The outer covering of the heart is called:
A. Myocardium B. Phloem
B. Endocardium C. Guard cells
C. Pericardium D. Stomata
D. Epicardium
798. The excretory product in birds is:
790. Which of the following prevents backflow of A. Urea
blood? B. Ammonia
A. Valves C. Uric acid
B. Arteries D. Carbon dioxide
C. Capillaries
D. Villi 799. The pigment in RBC that binds to oxygen is:
A. Hemoglobin
791. The process of making ATP using oxygen is B. Chlorophyll
called: C. Melanin
A. Anaerobic respiration D. Insulin
B. Photosynthesis
C. Aerobic respiration 800. The respiratory organ in fish is:
D. Transpiration A. Lungs
B. Skin
792. (Critical Thinking) Why is the left ventricle C. Trachea
thicker than the right ventricle? D. Gills
A. It contains more blood
B. It pumps blood to lungs 801. The number of chambers in a human heart is:
C. It pumps blood to entire body A. 2
D. It stores more oxygen B. 3
C. 4
793. The enzyme that breaks down fats is: D. 5
A. Pepsin
B. Lipase 802. The contraction of diaphragm causes:
C. Amylase A. Inhalation
D. Trypsin B. Exhalation
C. Coughing
794. The fluid part of blood is called: D. Digestion
A. Hemoglobin
B. Serum 803. In humans, which system is responsible for
C. Plasma hormone secretion?
D. Lymph A. Nervous system
B. Endocrine system
795. The lymphatic system helps in: C. Respiratory system
A. Respiration D. Circulatory system
B. Digestion
C. Immunity 804. Where does digestion of protein start?
D. Blood clotting A. Mouth
B. Stomach
796. The tiny pores on the underside of leaves are C. Small intestine
called: D. Esophagus
A. Xylem
B. Villi 805. Which part of the digestive tract has finger-like
C. Stomata projections for absorption?
D. Chloroplast A. Large intestine
B. Stomach
797. In plants, transport of food occurs through: C. Small intestine
A. Xylem D. Rectum
 D. Collecting duct
806. The human body gets most of its energy from:
A. Fats 814. The exchange of gases in alveoli occurs
B. Proteins through:
C. Vitamins A. Active transport
D. Carbohydrates B. Endocytosis
C. Diffusion
807. (Analytical) A person with kidney failure must D. Osmosis
undergo:
A. Endoscopy 815. Which is the correct sequence of blood flow
B. Dialysis through the heart?
C. Vaccination A. Atrium → Artery → Vein → Ventricle
D. Transfusion B. Vein → Atrium → Ventricle → Artery
C. Artery → Vein → Atrium → Ventricle
808. Carbon dioxide is transported in blood mainly D. Ventricle → Atrium → Artery → Vein
as:
A. Gas in RBC 816. What is the ultimate source of energy for all
B. Bicarbonate ions living organisms?
C. Carbonic acid A. Water
D. CO₂ bubbles B. Glucose
C. Sunlight
809. In human excretion, the final product is D. ATP
released through:
A. Ureter 817. Which of these is the most energy-efficient
B. Nephron respiration?
C. Urethra A. Anaerobic in humans
D. Collecting duct B. Aerobic in plants
C. Anaerobic in yeast
810. The cell organelle responsible for respiration D. Aerobic in animals
is:
A. Nucleus 818. Where does digestion of carbohydrates begin
B. Mitochondria in humans?
C. Chloroplast A. Stomach
D. Ribosome B. Mouth
C. Small intestine
811. The muscles of which organ help in breathing? D. Liver
A. Heart
B. Lungs 819. What structure in plant roots helps absorb
C. Diaphragm water and minerals?
D. Stomach A. Stomata
B. Root hairs
812. Which of these blood vessels has valves to C. Xylem
prevent backflow of blood? D. Phloem
A. Arteries
B. Veins 820. Which excretory product is formed by the
C. Capillaries breakdown of proteins?
D. Aorta A. Ammonia
B. Urea
813. Which part of the nephron reabsorbs water C. Uric acid
and nutrients? D. All of these
A. Bowman’s capsule
B. Glomerulus 821. (Critical Thinking) Why is breathing faster
C. Loop of Henle during exercise?
A. To balance body temperature 829. Which enzyme is present in saliva?
B. To reduce digestion A. Pepsin
C. To supply more oxygen to muscles B. Lipase
D. To cool down lungs C. Amylase
D. Trypsin
822. Which part of the brain controls the heartbeat
and breathing? 830. The blood vessel that carries blood from
A. Cerebrum kidney to heart is:
B. Cerebellum A. Renal artery
C. Medulla B. Hepatic vein
D. Spinal cord C. Renal vein
D. Vena cava
823. The flap that prevents food from entering the
windpipe is: 831. (Analytical) A person has swollen feet and high
A. Glottis urea levels in blood. Which organ is likely
B. Uvula malfunctioning?
C. Epiglottis A. Liver
D. Pharynx B. Heart
C. Kidney
824. In a plant, phloem transports: D. Lungs
A. Water
B. Minerals 832. Oxygen released during photosynthesis comes
C. Food from:
D. Oxygen A. CO₂
B. Glucose
825. In plants, which of these is an excretory C. Water
product? D. Chlorophyll
A. Oxygen
B. Carbon dioxide 833. In anaerobic respiration, the energy yield is:
C. Resin A. Higher than aerobic
D. Water B. Equal to aerobic
C. Lower than aerobic
826. The muscular organ that mixes food with D. Same in both
gastric juice is:
A. Liver 834. Which is a part of the human excretory
B. Small intestine system?
C. Stomach A. Liver
D. Esophagus B. Kidney
C. Lung
827. The total number of pulmonary veins in D. Intestine
humans is:
A. 1 835. Blood returning from the body enters which
B. 2 chamber of the heart first?
C. 3 A. Left atrium
D. 4 B. Left ventricle
C. Right atrium
828. Which blood component helps fight D. Right ventricle
infections?
A. RBC 836. The primary function of chlorophyll in
B. WBC photosynthesis is:
C. Plasma A. Release oxygen
D. Platelets B. Absorb sunlight
C. Store glucose
D. Split water C. Transpiration
D. Excretion
837. Water enters root hair cells by:
A. Osmosis 845. Which of these processes requires energy from
B. Active transport ATP?
C. Diffusion A. Diffusion
D. Transpiration B. Osmosis
C. Active transport
838. Which gas is expelled by lungs during D. Evaporation
exhalation?
A. Nitrogen 846. The inner lining of the small intestine has:
B. Oxygen A. Alveoli
C. Carbon dioxide B. Villi
D. Hydrogen C. Nephrons
D. Stomata
839. The rhythmic beating of the heart is due to:
A. Muscles 847. The heart pumps oxygenated blood into:
B. Bones A. Pulmonary artery
C. Electrical signals B. Pulmonary vein
D. Blood pressure C. Aorta
D. Vena cava
840. Blood pressure is measured using:
A. Barometer 848. Which of the following organisms uses
B. Sphygmomanometer tracheae for breathing?
C. Thermometer A. Frog
D. ECG machine B. Earthworm
C. Insect
841. (Critical Thinking) If a person breathes only D. Fish
through the mouth, which process may be less
efficient? 849. Blood is prevented from flowing backward by:
A. Digestion A. Arteries
B. Air filtration B. Veins
C. Blood circulation C. Valves
D. Hearing D. Pressure

842. What is the main nitrogenous waste in human 850. (Analytical) Why do leaves look wilted in the
urine? afternoon?
A. Ammonia A. Less sunlight
B. Uric acid B. Closed stomata
C. Urea C. High transpiration rate
D. Creatinine D. Low water absorption

843. Which component of the digestive system has 851. In which organ does the absorption of
both endocrine and exocrine functions? digested food mainly occur?
A. Liver A. Stomach
B. Stomach B. Small intestine
C. Pancreas C. Liver
D. Small intestine D. Large intestine

844. The breakdown of food molecules in cells to 852. Which part of the human body acts as a
release energy is: double pump?
A. Photosynthesis A. Liver
B. Respiration B. Kidney
C. Heart C. Swelling in limbs
D. Lungs D. Fast heartbeat

853. What is the role of hydrochloric acid in the 861. Which part of the root absorbs water and
stomach? minerals?
A. Emulsifies fat A. Cortex
B. Activates pepsin B. Root cap
C. Absorbs protein C. Root hairs
D. Neutralizes food D. Endodermis

854. Which part of the brain is responsible for 862. Which of the following is not a function of the
voluntary actions? liver?
A. Cerebrum A. Detoxification
B. Cerebellum B. Production of bile
C. Medulla C. Absorption of nutrients
D. Spinal cord D. Storage of glycogen

855. In photosynthesis, glucose is stored as: 863. The main excretory organ in humans is:
A. Starch A. Liver
B. Cellulose B. Skin
C. Protein C. Lungs
D. Sucrose D. Kidney

856. Which structure regulates the opening and 864. What is the product of anaerobic respiration in
closing of stomata? muscles?
A. Root hair A. Alcohol
B. Xylem B. Carbon dioxide
C. Guard cells C. Lactic acid
D. Phloem D. Glucose

857. The liquid waste excreted by humans is: 865. Which process removes excess water from the
A. Urea plant body?
B. Urine A. Photosynthesis
C. Sweat B. Respiration
D. Carbon dioxide C. Transpiration
D. Guttation
858. What is the main function of xylem?
A. Food transport 866. Which chamber of the heart receives
B. Water transport oxygenated blood?
C. Gas exchange A. Right atrium
D. Photosynthesis B. Left atrium
C. Right ventricle
859. The number of nephrons in each kidney is D. Pulmonary artery
approximately:
A. 1 million 867. The lungs are protected by:
B. 10,000 A. Ribs
C. 100,000 B. Diaphragm
D. 5 million C. Skull
D. Spine
860. (Critical Thinking) A person has a blocked
lymph vessel. What problem may occur? 868. The breakdown of food in the presence of
A. Poor digestion oxygen is called:
B. Fatigue A. Fermentation
B. Anaerobic respiration C. ATP
C. Aerobic respiration D. NADP
D. Combustion
877. Which gas is needed for aerobic respiration?
869. Which of the following is not a part of the A. Nitrogen
human circulatory system? B. Oxygen
A. Heart C. Carbon dioxide
B. Blood D. Hydrogen
C. Lungs
D. Blood vessels 878. The food pipe is also called:
A. Trachea
870. The human heart is made up of: B. Esophagus
A. Smooth muscle C. Pharynx
B. Skeletal muscle D. Bronchus
C. Cardiac muscle
D. Voluntary muscle 879. Which of these organisms performs
photosynthesis?
871. (Critical Thinking) Why do veins have thinner A. Fungi
walls than arteries? B. Amoeba
A. They carry oxygen-rich blood C. Algae
B. They carry blood under low pressure D. Hydra
C. They transport nutrients
D. They are longer 880. Which part of the plant conducts food?
A. Xylem
872. What is the pigment responsible for B. Phloem
photosynthesis? C. Cambium
A. Hemoglobin D. Cortex
B. Chlorophyll
C. Melanin 881. (Analytical) A person cannot produce bile.
D. Keratin Which process will be affected?
A. Protein digestion
873. Which part of the kidney filters blood? B. Fat digestion
A. Ureter C. Carbohydrate digestion
B. Glomerulus D. Vitamin absorption
C. Loop of Henle
D. Collecting duct 882. The small pores in leaves for gas exchange are:
A. Lenticels
874. The main function of white blood cells is: B. Stomata
A. Oxygen transport C. Hydathodes
B. Blood clotting D. Chloroplasts
C. Fighting infection
D. Carrying nutrients 883. The contraction of which muscle helps in
breathing?
875. The number of chromosomes in human A. Cardiac
gametes is: B. Diaphragm
A. 46 C. Voluntary
B. 44 D. Biceps
C. 23
D. 22 884. Blood is a:
A. Tissue
876. The energy currency of the cell is: B. Organ
A. DNA C. Cell
B. RNA D. Organ system
 893. Which part of the leaf carries out
885. Water absorption by root hairs is due to: photosynthesis?
A. Diffusion A. Stomata
B. Osmosis B. Xylem
C. Active transport C. Mesophyll
D. Transpiration D. Guard cells

886. The enzyme that digests protein in the 894. The main nitrogenous waste in birds is:
stomach is: A. Urea
A. Amylase B. Ammonia
B. Pepsin C. Uric acid
C. Lipase D. Creatinine
D. Trypsin
895. The circulatory system is responsible for:
887. (Critical Thinking) If stomata remain closed A. Gas exchange
during the day, the plant will: B. Absorption of water
A. Produce more food C. Transport of nutrients and oxygen
B. Conserve water D. Removal of bile
C. Undergo more transpiration
D. Absorb more CO₂ 896. Transpiration pulls water through:
A. Phloem
888. Which blood vessel carries oxygen-rich blood B. Roots
from lungs to heart? C. Stomata
A. Aorta D. Xylem
B. Pulmonary vein
C. Pulmonary artery 897. (Analytical) A person has damaged villi in the
D. Vena cava small intestine. Which will be affected?
A. Digestion
889. Lymph is a fluid that is similar to: B. Absorption
A. Plasma C. Excretion
B. RBC D. Respiration
C. Bile
D. Urine 898. The largest gland in the human body is:
A. Pancreas
890. Most digestion occurs in the: B. Liver
A. Mouth C. Thyroid
B. Esophagus D. Pituitary
C. Stomach
D. Small intestine 899. Which part of the nephron collects urine?
A. Loop of Henle
891. The wall of alveoli is: B. Bowman’s capsule
A. Thick and rigid C. Collecting duct
B. Thin and permeable D. Glomerulus
C. Elastic and thick
D. Covered with mucus 900. A red blood cell lives for about:
A. 30 days
892. What is formed when glucose is broken down B. 60 days
without oxygen? C. 90 days
A. Water D. 120 days
B. Alcohol
C. Lactic acid 901. The lungs are located in:
D. ATP A. Cranial cavity
B. Abdominal cavity
C. Thoracic cavity 910. (Critical Thinking) A fish out of water dies
D. Pelvic cavity quickly. Why?
A. Gills collapse and cannot absorb oxygen
902. Which one of these is a part of the lymphatic B. It loses water
system? C. Heart stops functioning
A. Artery D. Blood circulation stops
B. Vein
C. Lymph node 911. The urinary bladder stores:
D. Capillary A. Blood
B. Sweat
903. The main function of mitochondria is: C. Urine
A. Protein synthesis D. Bile
B. Lipid storage
C. Energy production 912. The process of excretion in humans is carried
D. Photosynthesis out by:
A. Skin
904. Which of these is a connective tissue? B. Lungs
A. Skin C. Kidneys
B. Bone D. Liver
C. Muscle
D. Nerve 913. The two types of respiration are:
A. Aerobic and anaerobic
905. The pulmonary artery carries: B. Oxygen and carbon dioxide
A. Oxygen-rich blood C. Lactic and alcohol
B. Oxygen-poor blood D. Respiratory and digestive
C. Plasma only
D. WBC 914. Which of the following occurs during the
process of transpiration?
906. Which of the following aids in blood clotting? A. Water absorption by roots
A. WBC B. Water loss through leaves
B. RBC C. Oxygen release through stomata
C. Platelets D. Nutrient transport in plants
D. Plasma
915. The part of the brain that controls breathing is
907. Carbon dioxide is carried in blood in the form the:
of: A. Cerebellum
A. Dissolved gas B. Medulla oblongata
B. Bicarbonate ions C. Cerebrum
C. Carbonic acid D. Thalamus
D. All of these
916. The process by which plants synthesize food
908. In plants, gaseous exchange occurs through: using sunlight is:
A. Stomata A. Digestion
B. Xylem B. Respiration
C. Phloem C. Photosynthesis
D. Root hairs D. Transpiration

909. The hormone that regulates blood sugar is: 917. The human digestive system consists of how
A. Adrenaline many organs?
B. Insulin A. 5
C. Thyroxine B. 8
D. Estrogen C. 10
D. 12
 B. Phloem
918. The breakdown of glucose to release energy in C. Cambium
the presence of oxygen occurs in: D. Epidermis
A. Cytoplasm
B. Mitochondria 926. The process of removing metabolic waste from
C. Nucleus the body is known as:
D. Ribosome A. Respiration
B. Excretion
919. Which of the following is not a function of the C. Digestion
circulatory system? D. Absorption
A. Transporting oxygen
B. Transporting nutrients 927. The part of the plant where most
C. Transporting waste products photosynthesis takes place is:
D. Producing hormones A. Root
B. Stem
920. Which of the following cells are responsible for C. Leaf
the immune response in humans? D. Flower
A. Red blood cells
B. Platelets 928. Which of the following is true about the
C. White blood cells human heart?
D. Muscle cells A. It has 4 chambers
B. It pumps oxygen-poor blood to the body
921. The process in which plants absorb water from C. It is composed of smooth muscle
the soil is called: D. It receives oxygenated blood from the body
A. Photosynthesis
B. Transpiration 929. Which organ produces bile in humans?
C. Osmosis A. Stomach
D. Diffusion B. Pancreas
C. Liver
922. Which of the following is the main site for D. Small intestine
nutrient absorption in humans?
A. Stomach 930. (Critical Thinking) Why is the surface area of
B. Small intestine the small intestine highly folded?
C. Large intestine A. To increase absorption of nutrients
D. Liver B. To store nutrients
C. To produce enzymes
923. The energy required for active transport is D. To reduce water loss
provided by:
A. Glucose 931. Which blood vessels carry blood away from
B. ATP the heart?
C. Oxygen A. Veins
D. Fat B. Arteries
C. Capillaries
924. In humans, most of the digestion of food takes D. Lymphatic vessels
place in:
A. Mouth 932. The blood vessel that connects the heart to
B. Stomach the lungs is called:
C. Small intestine A. Pulmonary vein
D. Large intestine B. Pulmonary artery
C. Aorta
925. The tissue responsible for transporting water D. Vena cava
in plants is:
A. Xylem 933. The process of removing undigested food from
the body is called:
A. Absorption 941. The function of the diaphragm in humans is to:
B. Excretion A. Control heartbeat
C. Digestion B. Assist in digestion
D. Egestion C. Assist in breathing
D. Protect the lungs
934. The function of villi in the small intestine is to:
A. Secrete digestive enzymes 942. The absorption of digested food in humans
B. Increase the surface area for absorption occurs mainly in the:
C. Transport nutrients to the blood A. Large intestine
D. Protect the intestines from infection B. Rectum
C. Small intestine
935. The end product of protein digestion in D. Stomach
humans is:
A. Amino acids 943. In human excretion, urine is produced by the:
B. Fatty acids A. Kidneys
C. Glucose B. Liver
D. Glycerol C. Lungs
D. Skin
936. Which of the following helps in the formation
of urine? 944. Which of the following is the process by which
A. Glomerulus oxygen is transported in the blood?
B. Liver A. Through hemoglobin in RBCs
C. Pancreas B. Dissolved in plasma
D. Small intestine C. Attached to platelets
D. Through white blood cells
937. (Analytical Thinking) A person is unable to
digest fats properly. Which of the following organs 945. What is the source of energy in the body
is most likely to be damaged? during the process of respiration?
A. Stomach A. Protein
B. Liver B. Carbohydrates
C. Pancreas C. Lipids
D. Kidney D. ATP

938. Which of these processes produces the most 946. The gas that is released during photosynthesis
ATP in human cells? is:
A. Fermentation A. Oxygen
B. Glycolysis B. Carbon dioxide
C. Aerobic respiration C. Nitrogen
D. Anaerobic respiration D. Methane

939. The root of a plant absorbs water through: 947. Which of the following is a result of aerobic
A. Root cap respiration in humans?
B. Root hairs A. Lactic acid
C. Xylem B. Carbon dioxide and water
D. Stomata C. Alcohol and carbon dioxide
D. Oxygen and glucose
940. Which of the following statements is true
about the excretion in plants? 948. Which process occurs in both plants and
A. Plants excrete nitrogenous waste through leaves animals to release energy from food?
B. Plants excrete carbon dioxide through roots A. Photosynthesis
C. Plants excrete oxygen through leaves B. Fermentation
D. Plants excrete nitrogen in the form of urea C. Respiration
D. Transpiration B. Digestion of food
C. Storage of bile
949. The process of taking in oxygen and expelling D. Absorption of nutrients
carbon dioxide is known as:
A. Digestion 957. (Critical Thinking) Why do humans need to
B. Respiration excrete nitrogenous waste?
C. Excretion A. It is toxic and must be removed
D. Transpiration B. It is used to make proteins
C. It is stored in the kidneys for later use
950. Which of the following is not a part of the D. It helps in digestion
human respiratory system?
A. Trachea 958. The waste product produced during anaerobic
B. Bronchi respiration in yeast is:
C. Stomach A. Lactic acid
D. Lungs B. Alcohol
C. Carbon dioxide
951. Which of these is not a feature of the process D. Glucose
of photosynthesis?
A. Occurs in chloroplasts 959. What is the end product of cellular respiration
B. Requires sunlight in humans?
C. Produces glucose A. Oxygen
D. Occurs at night B. Glucose
C. Carbon dioxide and water
952. What is the function of chloroplasts in plant D. Lactic acid
cells?
A. Photosynthesis 960. The process by which cells break down glucose
B. Respiration to release energy is known as:
C. Digestion A. Photosynthesis
D. Reproduction B. Fermentation
C. Respiration
953. The process of breathing in and out of air is D. Transpiration
called:
A. Respiration 961. (Analytical Thinking) Why do plants need
B. Inspiration nitrogen for their growth?
C. Exhalation A. For making chlorophyll
D. Ventilation B. For making glucose
C. For protein synthesis
954. The enzyme present in saliva that breaks down D. For respiration
starch is:
A. Pepsin 961. (Critical Thinking) What would happen if 2
B. Trypsin essential enzymes were removed from the
C. Amylase digestive process?
D. Lipase A. Digestion would speed up
B. Digestion would stop partially or fully
955. The human body eliminates waste products C. More energy would be produced
through the: D. Photosynthesis would occur in animals
A. Heart
B. Skin 962. (Critical Thinking) What would happen if 3
C. Kidneys essential enzymes were removed from the
D. Stomach digestive process?
A. Digestion would speed up
956. The primary function of the large intestine is: B. Digestion would stop partially or fully
A. Absorption of water C. More energy would be produced
D. Photosynthesis would occur in animals D. Maintain temperature

963. (Critical Thinking) What would happen if 4 965. Why is the left ventricle more muscular than
essential enzymes were removed from the the right ventricle?
digestive process? A. It pumps blood to the lungs
A. Digestion would speed up B. It pumps blood to the brain
B. Digestion would stop partially or fully C. It receives blood from the lungs
C. More energy would be produced D. It pumps blood to the entire body
D. Photosynthesis would occur in animals
966. How does saliva aid in digestion?
964. (Critical Thinking) What would happen if 5 A. Emulsifies fats
essential enzymes were removed from the B. Breaks down proteins
digestive process? C. Neutralizes acids
A. Digestion would speed up D. Begins digestion of starch
B. Digestion would stop partially or fully
C. More energy would be produced 967. What role does hydrochloric acid play in the
D. Photosynthesis would occur in animals stomach?
A. Absorbs nutrients
965. (Critical Thinking) What would happen if 1 B. Activates pepsin enzyme and kills microbes
essential enzyme were removed from the digestive C. Digests fats
process? D. Prevents ulcers
A. Digestion would speed up
B. Digestion would stop partially or fully 968. Which part of the nephron is responsible for
C. More energy would be produced filtration of blood?
D. Photosynthesis would occur in animals A. Loop of Henle
B. Collecting duct
961. (Analytical Thinking) Which process in the C. Bowman’s capsule
human body is directly responsible for energy D. Renal artery
release?
A. Inhalation 969. Why do desert plants have fewer stomata?
B. Respiration A. To increase oxygen intake
C. Digestion B. To avoid dust
D. Circulation C. To conserve water
D. To improve photosynthesis
962. Why do arteries have thick elastic walls?
A. To allow exchange of gases 970. How does anaerobic respiration differ from
B. To prevent blood clotting aerobic respiration?
C. To withstand high pressure of blood pumped from A. Uses oxygen
the heart B. Produces more energy
D. To store extra blood C. Produces lactic acid or ethanol
D. Occurs in mitochondria
963. Which structure prevents food from entering
the windpipe? 971. What is the function of guard cells in plants?
A. Epiglottis A. Transport food
B. Trachea B. Support the leaf
C. Esophagus C. Control opening and closing of stomata
D. Diaphragm D. Perform photosynthesis

964. What is the main function of platelets in 972. Which pigment in plants traps sunlight for
blood? photosynthesis?
A. Transport oxygen A. Xanthophyll
B. Fight infection B. Chlorophyll
C. Help in blood clotting C. Anthocyanin
D. Carotene D. To make chlorophyll

973. Why do veins have valves? 981. How does the diaphragm help in breathing?
A. To regulate oxygen A. Pushes food
B. To filter blood B. Contracts to pull air into lungs
C. To prevent backflow of blood C. Opens alveoli
D. To carry nutrients D. Closes trachea

974. What is the function of bile in digestion? 982. What happens to the rate of breathing during
A. Breaks protein exercise?
B. Absorbs nutrients A. Remains unchanged
C. Emulsifies fats B. Decreases
D. Neutralizes acid C. Increases to meet oxygen demand
D. Stops temporarily
975. Which part of the brain controls involuntary
actions like heartbeat? 983. Why is the small intestine very long and
A. Cerebellum coiled?
B. Cerebrum A. To allow time for digestion
C. Medulla oblongata B. For nutrient absorption
D. Hypothalamus C. To trap food
D. To mix bile
976. Why does lactic acid accumulate in muscles
after vigorous exercise? 984. Which part of the heart receives oxygenated
A. Excess oxygen supply blood from the lungs?
B. Low glucose levels A. Right atrium
C. Anaerobic respiration B. Left atrium
D. Protein breakdown C. Left ventricle
D. Right ventricle
977. Which gas is a by-product of aerobic
respiration? 985. What is emulsification of fats?
A. Nitrogen A. Absorption of fat molecules
B. Oxygen B. Breaking down proteins
C. Carbon dioxide C. Converting fats to carbohydrates
D. Methane D. Breaking large fat globules into smaller ones

978. Why are mitochondria called the powerhouse 986. Which organ removes nitrogenous waste from
of the cell? the body?
A. They store food A. Liver
B. They synthesize proteins B. Lungs
C. They produce energy in the form of ATP C. Kidney
D. They break down waste D. Skin

979. What will happen if the epiglottis does not 987. What would happen if xylem is removed from
function properly? a plant?
A. Saliva secretion increases A. Photosynthesis increases
B. Food enters the windpipe B. Water transport stops
C. Gas exchange stops C. Leaves turn greener
D. Digestion is enhanced D. Food storage improves

980. Why is transpiration important for plants? 988. Why are alveoli suited for gas exchange?
A. To absorb minerals A. Thick walls and low surface area
B. For respiration B. Thin walls and large surface area
C. To cool the plant and pull water upward C. Muscular lining
D. Present near diaphragm A. They don’t need oxygen
B. Water does not have carbon dioxide
989. What happens during exhalation? C. Gills extract dissolved oxygen from water
A. Diaphragm contracts D. Gills store air
B. Rib cage expands
C. Lungs deflate and air moves out 998. How is carbon dioxide transported in the
D. Oxygen enters blood blood?
A. Only in RBCs
990. Which enzyme digests proteins in the stomach? B. Dissolved in plasma and as bicarbonate ions
A. Amylase C. By platelets
B. Lipase D. Through enzymes
C. Pepsin
D. Trypsin 999. Why are kidneys important in homeostasis?
A. Regulate heart rate
991. What is the function of phloem in plants? B. Maintain balance of water and salts
A. Transport water C. Aid in breathing
B. Transport minerals D. Control body movements
C. Transport food from leaves to other parts
D. Absorb sunlight 1000. What will happen if there is a blockage in the
coronary artery?
992. Why is photosynthesis considered an A. Kidney failure
endothermic reaction? B. Stroke
A. It releases heat C. Heart attack due to reduced oxygen supply to
B. It requires sunlight (energy input) heart
C. It forms acids D. Lung infection
D. It occurs in mitochondria

993. What happens if stomata remain closed during

the day?
A. More oxygen is released
B. Photosynthesis increases
C. Gas exchange and transpiration stop
D. Nutrient flow improves

994. Which component of blood fights infection?

A. Red blood cells
B. Platelets
C. Plasma
D. White blood cells

995. Why is water important in photosynthesis?

A. Provides oxygen
B. Absorbs sunlight
C. Acts as an enzyme
D. Maintains leaf color

996. Which part of the digestive system absorbs the

most nutrients?
A. Stomach
B. Liver
C. Small intestine
D. Large intestine

997. Why do fish use gills instead of lungs?