VB G YOR

HIGH

VIBG YOR HIGH

First Preliminary Examination
2024-2025
BIOLOGY
Grade: X Max. Marks: 80
Date: 06/1 2/2024 Time Allowed: 2 hour
INSTRUCTIONS:
Answer to this paper must be written onthe paper separately.
You will not be allowed to write during the first 15 minutes.
This time is to be spent in reading the question paper.
The time given at the head of this paper is the time allowed for writing the
answers.

The intended marks for the questions or parts of questions are given
alongside the questions.
Attempt allquestions from Section Iand any four questions from Section I.
This question paper contains 11 printed pages.

SECTIONI(40 marks)
{Attennpi ali questions from this Section.)

Question 1 Choose the correct answers to the questions from the given options. [15]
(Do not copy the question, write the correct answers only.)

() Monohybrid phenotypic ratio is: [1]

(a 3:1
(b) 2:3

(c) 9:3:3:1
(d) 1:2:1

(i) Assertion (A): DNA replication occurs during the G2 phaseof the cellcycle. [1]
Reason (R): The G2 phase is the final stage of interphase before mitosis
begins.

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(a) A is true, and R is false.

(b) Ais false, and R is true.

(c) Both A and R are true.
(d) Both A and Rare false.

(ii) Insectivorous plants close their leaves to entrap a living prey. This [1]
movement is as a result of loss of:
(a) Wall pressure
(b) Osmotic pressure
(c) Turgor pressure
(d) Root pressure

(iv) What does the term "population dernsity" refer io? [1]
v (a) The total number of peopie in a contry
(b) The birth rate in a specific region
(c) The number of people whho nigrate to acountry
(d) The number of people iving per unitarea

(v) Which of the following pollutants most harmful to the ozone layer? [1]
(a) Carbon monoxide
(b) Methane

(c) Chlorofluorocarbons (CFCs)

(d) Nitrogen oxides

(vi) The structure in the male reproductive system which store sperms:
(a) Seminal vesicles
(b) Prostate gland
(c) Epididymis
(d) Bulbourethral gland

(vii) Assertion(A): In human males, testes are extra-abdominal, present in a [1]

thin-waled sac of skin called scrotum.
ReasonA): Being in a separate sac, suspended from the body, the testes
escapes too much heat.
(a) Both assertion and reasons are true and the reason is the correct

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explanation of the assertio.

(b) Both assertion and reason are true but the reason is not the
correct explanation of the assertion.
(c) Assertion is true statement but reason is false.
(d) Both assertion and reason are false statements

[1]
(viii) Which among the following is the correct location of thyroid glands
in human body?
(a) Above the kidneys
(b) Below the kidneys
(c) Below the larynx
(d) Above the larynx

If there is an injury in ha hvpoihalamus region of the brain,

it is most [1]
(ix)
likely to affect:
(a) Regulation of body temyeratne
(b) Intelligence
(c) Muscular coordination during locomotion
(d) Short-term memory

form filtrate? [1]

(x) Which part of the nephron is responsible for filtering blood to
Glomerulus
(a)
(b) Loop of Henle
(c) Collecting duct
Proximal convoluted tubule
(d)

Which of the following statement is true about veins?

[1]
(xi)
(a) They carry blood away fromthe heart
(b) They have thick, muscular walls.
(c) They carry blood towards the heart
(d) They carry oxygen-rich blood only.

(xii) What is the full form of IAA? [1]

(a) Indole 2-acetic acid
(b) Indole 3-acetic acid

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(c) Indole 4-acetic acids

(d) Indole 3-ascorbic acid

(Xll) Which hormone is secreted by the pancreas and raises blood glucOse [1]
levels?

(a) Insulin

(b) Glucagon
(c) Thyroxine
(d) Cortisol

(xiv) Which of the following is the correct equation for photosynthesis? [1]
(a) 6CO, + 12H,0+ light energy ’ CoHz06 + 60,+ 6H20
(b) CsH,206 + 60, ’ 6CO, + 6H,0+ energy
(c) 6CO, + 12H,0+ lightenergy - CiH0, + 6H20
(d) 6CO, + 6H,0 CçH1, + 60, t energy

(xv) Which of the following faricrs wto NOT affect the rate of transpiration [1]
as measured by a potomeier?
(a) Temperature
(b) Light Intensity
(c) Soil pH
(d) Humidity

Question 2 () Name the following: [5]

(a) A
condition where both alleles of a gene are identical.
(b) The hormone which leads to sprouting of potato tuber.
(c) The study of human populations, including their s0ze, growth, density, and
distribution.

(d) The condition in which a person retains excess amounts of urea in his/her
body.
(e) The hormone that controls the rate of metabolism in the body.

(ii) Fillin the blanks with suitable words:

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Outer membrane Stroma

Granumn

Inner membrane Thylakoid

Photosynthesis is the process by which green plants convert [5]
glucose.
(1) energy into chemical energy which gets stored in the form of
During photosynthesis, plants take in (2)from the air through
small openings called (3). Photosynthesis can be divided into
two main stages: the (4) reactions, which occur in the
thylakoid membranes ivive the capture of light energy, and light
independent reactions. whicn lakes place in the (5) of the
chloroplast and involves the fixation of carbon dioxide into glucose.

(iii) Arrange and rewrite the terms in each group in the correct order so as [5]
to be in alogical sequence beginning with term that is underlined.

(a) Epidermis, soil water,endodermis, xylem

(b) Stuart Factor is released, Factor Xwith calcium convertsprothrombin into
thrombin, Thrombin with the presence of Ca? ions reacts with fibrincogen to
convert it into fibrin (insoluble), Injured tissues and platelets disintegrate at the
site of injury.
(c) Receptor, Brain/Spinal cord, Stimulus, Effector.
(d) Choroid,Sclera, Retina,Vitreous Humor.
(e) Blastocyst, Morula, Embryo, Foetus.

(iv) Choose the odd one out from the following termsand name the [5]
category to which the others belong:
(a) Potassium Chloride, Sodium Chloride, Uric Acid, Bile Pigments
(c) Intensity of sunlight, Water content of leaves, Humidity, Carbon dioxide.

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(d) Movement ofpollen tube in angiosperms and gymnosperms towards the

female gametophyte,Movement of fungi towards areas richer in fo0d,
Movement of tentacles of Drosera towards source of nutrition, Movement
of tendrils of pea plant towards stems of other plants
(e) Seminal vesicle, Prostate gland, Cervix, Cowper's gland

(v) Match the items given in column I with the most appropriate ones in [5]
column Il and rewrite the correct matching pairs.

Column| Column lI
(a) Cones ())Sensitive to low levels of illumination
(b) Rods (ii) Malleus
(c) Eustachian tube
(iti) Sensitive to high levels of illumination
(d) Attached to tympanum (iv) Equalizes air pressure
(e) Cochlear Canal (v) Perilymph
(vi) Endolymph
(vi) Stapes

SECTIONB
(Attempt any four questions from this section)

Question 3
[10]
() Define Photosynthesis.
(i) What is ovulation, and on which day of the menstrual cycle does it
usually [2]
0ccur?

(ii) Differentiate between Systole and Diastole based on the definition.

(iv) The diagram below represents a stage during cell division.
[2]
Study the same and then answer the questions that follow.

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(a) Name the part labelei (b}.

(b) ldentify the above stage and give a reason to support your answer.
(V) Three plants A, B and Care placed in a beaker containing water. The [3]
water in each beaker is covered with a layer of oil. The leaves were
removed from plant 'B' while plant 'C' was exposed to strong light.

(a) In which plant A, B or Cwould the water move up fastest? Give reason.

(b) Why is the water covered with oil?

Mention any one characteristic of root hair which promotes the process of
(c)
water absorption.

Question 4 [10]
() Gibberellins are widely used in horticulture. Give reason. [1]
(i) Give two examples of disorders which are X-linked. (2]

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velocity of wind. Give reason.

(i) Transpiration increases with the
(iv)

Bowmarn's
capsule

Proximal
covoiuted tubule

and
Observe the diagrarn abovs and iientify two differences between A
B
Draw a well labeiled diagram of human sperm and label the following: [3]
(v)
(a) The part which provides ATP for its activity.
(b) The part which secretes hyaluronidase.

Question 5
[10]
Mention one characteristic feature of a capillary. [1]
(i)
ldentify the fate of aRed Blood Cell when kept in: [2]
(i)
a. Hypertonic medium
b. Hypotonic medium
(ii) State the difference between Haematuriaand Glycosuria (based on the [2]
meaning)
Mention the function of: [2]
(iv)
a. Pupil
b. Vitreous humour
[3]
(v) Observe the diagram given below and answer the following questions.
 GYOR
HIGH

Spinal Cord
Receptor Synapse A

Sensory neuron

IntemeuIOn

Éffector
Matas neuron
(muscle)

(a) ldentify the part of neuron which is present in A and B.

(b) Explain the term Synapse.
(c) Mention any one function of the fluid which is present inthe cerntral canalof the
spinal cord.

Question 6 [10]
State Mendel's law of dominance. [1]
(i) Mention.two reasons for rapid rise of population in India. [2]
(ii) Differentiate between the functions of auxins and cytokinins based on:
a. Apical dominance
b. Effect on growth cells of a plant
(iv) Why is Pancreas known as an exo-endocrine gland? [2]
(v) Draw a well labeled diagram of a plasmolysed cell. [3]

Question7 [10]
Briefly explain the term Biomedical waste. [1]
(ü) In humans wisdom teeth is considered to be a vestigial organ. Give reason. [2]
(ii) The diagram below represents the simplified pathway of the circulation [2]
of blood. Study the same and answer the questions that follow:
 VIBG YOR
HIGH

HEAO

LLJNGa

HCART

SMANL
INTC3TINE

(a) Name the blood vessel which has the highest amount of glucose and amino
acids aftor a meal.
(b) Identify the blood vessels 5 and 7.
(iv) Ramapithecus is regarded as the pre-human ancestor. Give reasons.
(v) Observe the cross given belowand answer the questions that follow:
Axlal Round Teminal Winked
Parent-y AARR

Gametes’ AR AR ar

AaRr
AaAr Aafr AaRr
(a) Write the sclentific name of peaplarnt.
(b) Mention the phenotype ratio of F2 plants.
(c) List thegamotes which would be formed from the F1 hybrids.

Questlon 8
[10]
(() Define mutalion. [1]
(i) Correct and rewrite the incorrect statemenls. (2]
(a) Ollactory nerve is an oxample of spinal nerve.
(b) Dura maler is the innemost highly vascular layer of menings.
(ili) State difforence botwoon Vasoprossin and Insulin based on deficioncy (21

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disorder.
(iv) Study the given figure and answer the following questions: [2]

(a) List any onG iarnfui eñect of the above type of pollution.
(b) Mention any cae waY Cnrol the above.

(V) Draw neat labeiled úiagram of across section of an artery. [3]

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