1. the circulatory system
CHAPTER 1.2

2. Circulatory system:
Transports substances continuously around the entire body
Consists of :
Cardiovascular system : heart, blood vessels and blood
Lymphatic system: lymphatic vessels and lymphoid tissues within the spleen, thymus, tonsils, lymph nodes and lymph
Transports nutrients, water & O2 to body cells
Remove CO2 and other nitrogenous wastes from body cell
Consists of 3 components:
Medium
Vessels
Pump

3. a) medium/fluid
Required to carry materials around the circulatory system
In human & animals : BLOOD
Insects : HAEMOLYPMH
Composition of human blood
Plasma – 55%
Cellular Elements– 45 %

5. Fibrin and clotting factors Cellular components (45%)
Human Blood
Plasma (55%)
Serum
Fibrin and clotting factors
Cellular components (45%)
Erythrocytes (red blood cells)
Leucocytes (white blood cells)
Agranulocytes
Lymphocytes
Monocytes
Granulocytes
Neutrophils
Basophils
Eosinophils
Thrombocytes (platelets)

6. Cellular components of blood

8. a) Erythrocytes RED BLOOD CELLS 5 million per mm3 of blood
DO NOT HAVE :
Nucleus
mitochondria
ribosomes
Full of haemoglobin to bind O2 & CO2
Made in bone marrow
live for about 120 days
Destroyed & recycled in liver

10. adaptations HAVE NO NUCLEUS : provide more space for haemoglobin
Haemoglobin transports O2 – combined as oxyhaemoglobin – from lungs to the body tissues for respiration
Also carry CO2 as hydrogen-carbonate from the respiring tissues to the lungs
BICONCAVE DISC- SHAPED CELLS : increase the TSA/V ratio for optimum gaseous exchange
SMALL & FLEXIBLE: able to squeeze through narrow capillary walls

12. b) leucocytes WHITE BLOOD CELLS Colorless No hemoglobin
Larger than erythrocytes; fewer in number
≈ 7000 per mm3 of blood
No fix shape
have nucleus
Can change their shapes & squeeze through the walls of capillaries
Important in body mechanisms against disease
WHITE BLOOD CELLS
GRANULOCYTES
AGRANULOCYTES

13. a) Granulocytes Have : Capable of amoeboid movement
granular cytoplasm
lobed nucleus
Capable of amoeboid movement
engulf bacteria by phagocytosis
Produced in bone marrow
GRANULOCYTES
BASOPHIL
NEUTROPHIL
EOSINOPHIL

14. BASOPHIL NEUTROPHIL EOSINOPHIL
RAREST -1% of total leucocytes
NEUTROPHIL
MOST COMMON - Engulf bacteria by phagocytosis
EOSINOPHIL
Detoxify chemicals & reduce inflammation

16. Phagocytosis by granulocyte

17. b) Agranulocytes Have non-granular cytoplasm and a compact nucleus
MONOCYTES
LYMPHOCYTES
Have non-granular cytoplasm and a compact nucleus

18. a) Monocytes The largest of the five types of white blood cell
Produce in bone marrow
Have bean-shaped nucleus
Ingest bacteria by phagocytosis

19. b) Lymphocytes has large rounded nucleus
contains many genes : efficient antibody protein productions
Produced in the lymph glands & the lymphatic nodes
FUNCTIONS:
Produce antibodies
specific defense against toxins produced by bacteria and infecting germs

20. (c) Thrombocytes a.k.a PLATELETS Not a cells
tiny fragments of other cells (megakaryocytes)
Colorless, irregular shape, without nucleus
Made in bone marrow
last about 6-7 days

21. (c) Thrombocytes FUNCTIONS: Have amoeboid movements
Important in blood clotting & repairing damages tissues
Help to maintain the integrity of blood vessel wall

22. Blood plasma

24. Plasma Yellowish liquid
Serum : blood plasma with its clotting factors (such as fibrin) removed
90% water, 10% dissolved substances

25. Plasma consist of : Heat produced by respiration absorbed by plasma
dissolved gases, absorbed food molecules, excretory waste products, hormones & salts
Heat produced by respiration absorbed by plasma

26. b) Functions of blood Transport O2 & CO2
Transport absorbed food materials
Transport of excretory waste products
Deamination excess amino acids occur in _______?
Transport heat
Blood distribute heat from heat-producing sites (e.g. skeletal muscles) to areas of heat loss (e.g. skin)
Transport of hormones
Transport of water to tissues
b) Functions of blood

27. hAEMOLYMPH

29. c) Function of Haemolymph in Transport
the circulatory fluid in body cavities of insects
A.K.A ‘ insect blood’
Flows freely within the body cavity
makes direct contact with all the internal tissues & organ of insects
Contains water, amino acids, sugar, salts & white cell

30. c) Function of Haemolymph in Transport
the circulatory fluid in body cavities of insects
Transport hormones, nutrients, salt & metabolic wastes around the body
Does not contain haemoglobin or RBC
Does not transport O2 and CO2

31. The Structure of Human Blood Vessels

32. Tubes for the medium to flow through
Heart is connected to a series of tubes called blood vessels
BLOOD VESSELS:
Tubes for the medium to flow through
Main types of vessels: artery, arteriole, capillary, venule and vein
Each type of blood vessel has a different structure according to their function`

38. Aspect Artery Capillary Vein Vessels Structure of wall
Three layers – endothelium, smooth muscle & fibrous connective tissue
Single layer - endothelium
Thickness of wall
Thick
Very thin – single cell
Thinner than arteries
Relative diameter of lumen
Narrow
Very narrow – about the size of single erythrocyte
Wide
Direction of blood flow
Away from the heart
From arteries to vein
Towards the hearts
Valve
Absent
Present
Oxygen transported
Carries oxygenated blood (except pulmonary artery)
Arteriole carries oxygenated blood
Venule carries deoxgenated blood
Carries deoxygenated blood (except pulmonary vein)
Relative blood pressure
High
Gradually decreases from the arteriole end to the venule end
Lowest
Vessels

39. The circulatory systems in humans and other animals

40. Open circulatory system
Insects, crustaceans & mollusks
Heart pumps haemolymph through the aorta which branches into number of arteries that open into body cavity

41. Open circulatory system
Haemolymph
reaches the body cells directly
diffuses between body cells & re- enters the heart through open-ended veins

42. Closed circulatory system
Found in all vertebrates & some invert (e.g. earthworms)
Heart pumps blood rapidly through & within completely closed continuous system of vessel

43. Closed circulatory system
never comes in direct contact with body cells