8. Circulatory system in humans and
animals
• Circulatory system (CS) includes:
– Medium fluid that flows in CS (eg: animal :
blood; insects: haemolymph)
– Vesels arteries, veins and capillaries
– Pump muscular heart
12. Erythrocytes
• Small, biconcave disc
• Have no nucleus
• Great quantities of haemoglobin (which contains iron)
(Cells become bright red)
• Site of production: bone marrow
• Life span: 120 days
• Site of destruction: liver and spleen (by phagocytes)
• Ratio of erythrocytes to leucocytes 1000 : 1 (in normal person)
14. Leucocytes (White blood cells)
• Less numerous than eryhtrocytes.
• Have nuclei
• Do not have haemoglobin
• Larger than erythrocytes and do not have
fixed shapes.
• Site of production : bone marrow
• Site of growth and development: thymus
gland or lymph nodes
15. Cont.
Basic types of leucocytes:
Granulocytes (have granular cytoplasm and
lobed nuclei)
• Neutrophils
• Eusinophils
• Basophils
Agranulocytes (clear cytoplasm and no
lobed)
• Monocytes (largest)
• Lymphocytes (smallest)
17. Quizzes
1. The neutrophils are _______
A. Phagocytes
B. Leucocytes
C. Lymphocytes
D. Phosphate
2. Which leucocytes that help to control allergic
reaction?
A. Basophils
B. Eosinophils
C. Monocytes
D. Neutrophils
18. 3. Basophils secrete _________ to prevent blood clotting
A. Warfarin
B. Fibrinogen
C. Heparin
D. Walfarine
4. Which leucocytes that can move to the body tissues to
become phagocytic macrophage?
A. Basophils
B. Neutrophils
C. Eosinophils
D. Monocytes
19. 5. Some lymphocytes produce _________ to aid
in destruction of __________
A. Antibodies, homogens
B. Antibodies, pathogens
C. Hormones, pathogens
D. Enzymes, pathogens
23. Function of blood in transport
• Transport oxygen from the lungs to other
parts of the body (form 4)
• Transport absorbed food materials from the
digestive tract to body tissues (form 4)
• Transport waste products (form 4)
– Eg: carbon dioxide from body tissues to the lungs
– Urea to the kidneys
• Transport heat, hormones and water
24. Transport of heat,
hormones & water
• Body T can be regulated by blood by
distributing heat from heat-producing sites
(eg:muscles) to the skin.
• Hormones (eg:insulin & glucagon) produced
by endocrine glands (pancreas) transported by
blood to target organs (liver).
• Water is important to provide medium for
biochemical reaction.
25. Function of haemolymph
• Circulating blood-like fluid found in invertebrates
with open-circulatory systems
• Tubular heart pumps the haemolymph into
haemocoel.
• Haemolymph – bathes the tissues and internal
organ directly.
• Nutrients and hormones diffuse from
haemolypmh into the cells
• Waste products diffuse out from the cells into
haemolymph.
27. Structure of human blood vessels
Blood vessels : tubes that transport blood from one part to another.
Arteries Capillaries Veins
Transport blood away from Connect arterioles to Transport blood to the
the heart venules heart
Transport oxygenated Act as the sites for Transport deoxygenated
blood (except pulmonary exchange of substances blood (except pulmonary
artery) with the cells vein)
Thick muscular wall Thinnest wall, one cell Thinner wall
thickness
No valves except semilunar No valves Valves present to prevent
valves at the base of the back flow of blood
aorta and pulmonary
artery
Blood flows in pulses under No pulses. Pressure lower No pulses. Blood flows
high pressure than arteries but higher under lower pressure than
than veins arteries.
33. How blood is propelled through the
human circulatory system
• VIDEO
34. Lungs
Pulmonary veins
Vena cava
Right ventricle Left atrium
Tricuspid Bicuspid
valve
deO2 blood O2 blood valve
Right atrium Left ventricle
Aorta
Pulmonary
artery
Whole body
35. FAQ SPM
1. The diagram below shows the external view of the
human heart.
What is the blood vessel labeled W?
A. Carotid artery
B. Coronary artery
C. Subclavian artery
D. Systemic artery
41. 2. Valves ensure the haemolymph flow in one direction
1. When the heart relax, haemolymph re-enters ostia
Material exchange occurs
here. Haemolymph in
haemocoel carry nutrients
and waste products
42. Circulatory system in fish
• Single circulatory
system.
• Deoxygenated blood
Sinuses leaves the heart at high
pressure and passes
through the gills where
the gaseous exchange
occurs.
• Oxygenated blood flows
through the organs and
blood pressure drops.
43. Circulatory system in amphibians
(eg:frogs)
• Double circulatory system:
– Pulmonary circulation
– Systemic circulation
• Have three-chambered heart (2 atria & 1
ventricle)
• Mixing of oxygenated and deoxygenated
blood in ventricle. The mixed blood enters the
systemic circulation.
46. FAQ SPM
1. The diagram below shows a longitudinal section
of the human heart.
Which of the labeled parts, A, B, C or D, receives
blood from the lungs?
47. 2. The diagram shows the circulatory system of
a fish.
What are the organs P, Q and R?
P Q R
A Gills Lungs Stomach
B Stomach Lungs Gills
C Gills Heart Stomach
D Stomach Heart Gills
48. Circulatory system in humans
• Double circulatory system (blood passes through the
heart twice for each circuit)
– Pulmonary circulation
– Systemic circulation
• Two divisions of heart:
– Right side pump deoxygenated blood to the lungs
– Left side pump oxygenated blood to the body (except
lungs)
• Advantage: blood returns to the heart to be pumped
again will increase the blood pressure and flow rate,
thereby speeding up delivery O2 to the tissues and
organs.
49. Assignment 1.3
1. Draw and label a longitudinal section of
human heart.
2. List the functions of the different types of
leucocytes.
51. The necessities of blood clotting
• To prevent:
– serious blood loss
– the entry of microorganisms and foreign particles
into the blood
• To maintain:
– normal blood pressure
– circulation of blood in a a closed circulatory
system
55. FAQ SPM
1. The conversion of the soluble fibrinogen
present in blood plasma into the insoluble
fibrin is by
A. calcium ion
B. thrombin
C. thromboplastins
D. vitamin K
56. FAQ SPM
2. Fibrinogen, fibrin, thrombin and prothrombin
are necessary for blood clotting. Which of the
following is the correct sequence for the
involvement of these four substances during
blood clotting?
A. Prothrombin, thrombin, fibrinogen, fibrin
B. Thrombin, prothrombin, fibrin, fibrinogen
C. Fibrinogen, fibrin, prothrombin, thrombin
D. Fibrin, fibrinogen, thrombin, prothrombin
60. Assignment 1.4
1. List the advantages of blood clotting at the
site of damaged blood vessels.
2. Draw a schematic diagram to illustrate the
mechanism of blood clotting.
3. What would happen if a blood clot forms
a) In the brain
b) In the coronary artery
Editor's Notes
Haemocoel – fluid-filled spaces
Heomocel : body cavityHaemolymph : insect’s blood
1. Single circulatory system : blood flows through the heart only once for each complete circuit.2. Sinuses: collect deoxygenated blood before entering the atrium.