Welcome
Cambridge O/A
level/IGCSE/GCSE/Edex
cel/ AQA / IBDP (SL/HL)
Biology
Ms. Misbah Ashraf
1
BIOLOGY
Transport In Humans
CHAPTER NO 7
The Circulatory System
Function
• It transports nutrients from one part of our body
to another and removes excretory products from
the cells.
Components of Circulatory System
Blood Vessels Blood
Heart
Liquid (plasma) Solid (blood cells)
platelet white blood cells red blood cells
s
lymphocytes Phagocytes
Capillaries Veins Arteries Polymorphs Monocytes
Composition of Plasma
Water(90%) Dissolved Substances(10%)
Inorganic Respiratory
Hormones Proteins Excretory Food
salt gases
products
Helps in Insulin Fibrinogen Creatinine Glucose CO2,
maintaining Glucagon Globulin Urea Amino acids O2
pH of blood adrenaline Prothrombin Uric acid
(7.4) Albumin
▪Cl, HCO3, P,
S
Salts of Na
and K
Red Blood Cells
❖ Function
They carry oxygen in our body and carbon dioxide outside.
❖ Features
o Biconcave
To increase surface area o In Fetus red blood cells are formed
o No nucleus in liver and spleen.
To increase space o In adults red blood cells are made in
o Elastic bone marrow. (Sternum, Ribs,
Vertebrae)
To squeeze through narrow capillaries
o Hemoglobin
Gives red color to blood
o Have a diameter of 0.01 mm
o Life span 90-120 days
o Cannot reproduce → lack Nucleus
o Female: 4-4.5 million/ml Male: 5-5.5 million/ml
White Blood Cells
1. 5000-10,000/ml
2. No Hemoglobin
3. Defend body from diseases
4. Can change and squeeze through capillaries.
5. Life span varies.
6. Larger than red blood cells.
White Blood Cells
White Blood Cells
Lymphocytes Phagocytes
-Produce anti-bodies -Engulf viruses, bacteria, pathogens
-Larger, rounded nucleus and worn out cells.
-small cytoplasm
Agranulocytes
Polymorphs Monocytes
Granulocytes Agranulocytes
Multilobed nucleus Bilobed nucleus
Platelets
Fragments of Formed in Helps in blood
cell bone marrow clotting
Functions Of Blood
Functions Of Blood
Functions Of Blood
Functions Of Blood
Heart
▪ Four-chambered
▪ Stored in the pericardium in the left side of the chest
▪ Has pericardial fluid between membranes.
▪ The pericardial fluid reduces friction.
Left Atrium •Receives oxygenated blood from lungs through pulmonary vein.
Left Ventricle •Pumps blood to all parts of the body(except lungs) via aorta.
Bicuspid Valve •Prevents backflow of blood to left atrium
Right Atrium •Receives deoxygenated blood
Right Ventricle •Pumps blood to the lungs through pulmonary artery
Tricuspid Valve •Prevents backflow of blood to right atrium
Semi-lunar Valve •Prevents backflow of blood
Septum •Prevents mixing of oxygenated and deoxygenated blood
Aorta •Carries oxygenated blood
Pulmonary Artery •Carries deoxygenated blood to the lungs
Pulmonary Vein •Carries oxygenated blood from the lungs to the heart
Superior Vena •Returns deoxygenated blood from head and arms to heart
Cava
Inferior Vena Cava •Returns deoxygenated blood from lower limbs and organs to heart
oxygenated blood deoxygenated blood
deoxygenated blood oxygenated blood
systematic circulation pulmonary circulation
Blood Vessels
● Arteries Arterioles Capillaries
Venules Veins
Arteries Veins Capillaries
• Carry blood away from heart. • Carry blood towards heart. • Thin walled
•One- cell thick
• Have oxygenated blood • Have deoxygenated blood. To allow exchange of materials
(except pulmonary artery.) (except pulmonary vein) :
➢Glucose
• Thick walls • Thin walls ➢O2
➢ To withstand high pressure ➢ amino acids
• High blood pressure • Low blood pressure
from blood to cells and cells to
blood:
• Narrow lumen • Broad lumen
➢Waste materials
• More elastic walls • Less elastic walls ➢CO2
➢Urea
➢Creatinine
• No valves • Has valves
➢ To prevent backflow of blood
Organ Arteries Veins
Carry oxygenated blood from Carry deoxygenated blood from these
heart to these parts of body parts of body to heart
head and neck ➢ Carotid Artery ➢ Carotid Vein
forelimbs ➢ Subclavian Artery ➢ Subclavian Vein
liver ➢ Hepatic Artery ➢ Hepatic Vein
kidney ➢ Renal Artery ➢ Renal Vein
intestines ➢ Mesenteric Artery ➢ Hepatic Portal Vein
hind limbs ➢ Iliac Artery ➢ Iliac Vein
eyes ➢ Optic Artery ➢ Optic Vein
muscles of the heart ➢ Coronary Artery ➢ Coronary Vein
Types of Circulation
Double Circulation
• The blood passes the heart twice.
• In mammals.
Single Circulation
• The blood passes the heart only once.
• In Fishes
Heart Beat
❖Lub
produced by the closure of the ‘Tricuspid and
Bicuspid valves.’
❖ Dub
produced by the closure of the ‘semi-lunar valves.’
➢ One systole and diastole make one heart beat.
➢ The average number of heart beats of an adult is
72times/min.
Blood Pressure
• It is the force of the blood exerted on the blood vessels.
▪ Varies in different parts of the body.
▪ During the Ventricle Diastole, the blood pressure is minimum (80 mm
of mercury)
▪ During the Ventricle Systole, the blood pressure is maximum (120 mm
of mercury)
▪ Measured by sphygmomanometer.
Heart Diseases
Cardiac Disorders
Myocardial infraction Arteriosclerosis
Death of muscle tissues Blockage of arteries
Treatment
Atherosclerosis Thrombus
fat deposition Blood Clot
Angioplasty Bypass
Widening of artery by Grafting of extra
Stent and Balloon Catheter. vein into heart.
Angiography Angiogram
A procedure where an X-ray During an angiogram, substances that
of the coronary arteries is are opaque to X-rays are inserted into
taken after injection of a dye the bloodstream. The images of the
to look for blockages. path they take through blood vessels
can be diagnostically useful.
STENT
BYPASS
ANGIOGRAPHY
ANGIOGRAM
Due to high pressure some of the
components of plasma (except RBCs
and proteins) move out of the
capillaries as it is selectively
permeable. This fluid is known as the
‘Interstitial fluid or the Tissue Fluid.’
In the Venules side the tissue fluid is
again absorbed into the capillaries.
The Lymph capillaries collect this fluid
and the Lymph vessels deposit it in
the blood.
