Blood functions to transport oxygen, nutrients, hormones, heat, antibodies, and clotting factors throughout the body. It is composed of plasma and three main cell types: red blood cells, which carry oxygen; white blood cells, which fight infection; and platelets, which help form clots to stop bleeding. When a blood vessel is damaged, hemostasis occurs through vasoconstriction, platelet plug formation, blood clotting via fibrin, and fibrinolysis to remove the clot and allow healing.

1. THE BLOOD
MADE BY
Ms. JOYCE PRABHUDAS RANADIVE
ASSISTANT PROFESSOR
SHARDA UNIVERSITY (SUSNR)

2. FUNCTIONS OF BLOOD
1. Transportation of Oxygen
2. Provide nutrients to the cells
3. Transport hormones
4. Transports heat
5. Transports antibodies, WBCs and platelets
6. Transports clotting factors

3. CHARACTERSTICS OF BLOOD
Blood is composed of clear, straw coloured
and watery fluid called PLASMA.
Blood makes up to 70% of body weight.

5. PLASMA
Constituents of plasma are:
1. Plasma proteins (Albumins, Globulins and
Clotting factors)
2. Electrolytes (Na,K,Ca)
3. Nutrients from digested food
4. Waste materials
5. Hormones
6. Gases

6. PLASMA PROTEINS
a) Albumin: It is a protein that keeps the intra-
vascular fluid inside the vessels and prevents
from leakage.

7. It’s function is:
 to maintain plasma osmotic pressure
 to carry free fatty acids, drugs and steroid
hormones

8. b) Globulins: It is a protein that protects the
body from pathogenic reactions.

9. It’s function is:
 to act as an Antibody produced by
lymphocytes
transportation of Hormones and Salts
(Thyroxine and Transferrin)
inhibiting some enzyme action like Trypsin

10. c) Clotting factors: It is responsible for
coagulation (clotting) of blood. The most
abundant clotting factor is FIBRIN.

11. ELECTROLYTES
1. Electrolytes are minerals in
blood and other body fluids
that carry an electric charge.
2. Electrolytes affect how body
functions in many ways,
including:
• the amount of water in
body
• the acidity of blood (pH)
muscle function
3. Normal pH 7.35-7.45

12. NUTRIENTS
The products of digestion
eg; glucose, amino acids
and fatty acids are
absorbed from alimentary
tract.
Minerals, salts and
vitamins they are used by
body cells for energy, heat,
repair and replacement
and for synthesis of blood.

13. WASTE PRODUCTS
Urea, creatinine and uric acid are the waste
products of protein metabolism.
They are formed in the liver and carried in the
blood to the kidneys for excretion.

14. HORMONES
These are synthesized by endocrine glands.
Hormones are passed directly from the
endocrine cells into the blood.

15. GASES
Oxygen, carbon-dioxide and nitrogen are
transported in the body in plasma.

17. There are 3 types of blood cells:
1. Erythrocytes (Red Blood Cells)
2. Leukocytes (White Blood Cells)
3. Thrombocytes (Platelets)

18. ERYTHROCYTES (RED BLOOD CELLS)
99% of all blood cells in the body are RBC’s.
It’s main function is to transport oxygen and
carbon-dioxide.
Life span of RBC’s is 120 days.
It takes 7 days for RBC’s to develop. This
process is called ERYTHROPOIESIS.

19. Immature RBC’s are called RETICULOCYTES.
Mature within 2 days into ERYTHROCYTES.
RBC’s are formed with vitamin B12 and Folic
acid synthesis which is present in dairy
products, meat and green leafy vegetables.

20. MATURE WITHIN
7 DAYS
PRODUCTION OF RBC IN
RED BONE MARROW
SYNTHESIS OF RBC FROM GREEN
LEAFY VEGETABLE, MEAT AND DAIRY
PRODUCTS

21. HEMOLYSIS IN
SPLEEN
MATURE ERTHYROCYTES LIVE FOR
120 DAYS

22. LEUKOCYTES (WHITE BLOOD CELLS)
WBC’s detect foreign or abnormal antigen and
destroy through the process of
PHAGOCYTOSIS.
There are 2 types of WBC’s:
1. Granulocytes
2. Agranulocytes

23. GRANULOCYTES
a) Neutrophils: These are small, fast scavengers
that protect against bacterial invasion and
remove dead cells and debris from damaged
tissues. They are attracted by a chemical
called CHEMOTAXINS released by infection.

24. b) Eosinophils: They are phagocytic leukocytes
and are responsible in eliminating parasitic
infections like Worm Infestation.
c) Basophils: They are associated with allergic
reactions and other substance that promote
inflammation like allergic to dust, pollen,
perfume etc.

25. AGRANULOCYTES
a) Monocytes:
o Largest WBC’s
o Highly motile
o Phagocytic

26. b) Lymphocytes
o Smaller than Monocytes
o Found in lymph nodes and spleen
o Produce 2 types of lymphocytes
T-Lymphocytes
B- Lymphocytes

27. THROMBOCYTES (PLATELETS)
Life span 7-10 days
Promotes HAEMOSTASIS (stopping of
bleeding)
Normal platelet count is 200000 to
350000/mm3
Kidney releases a substance called
THROMBOPOIETIN which stimulate platelet
synthesis

28. HAEMOSTASIS
When blood vessel is damaged, loss of blood is
stopped and healing occurs within 15 seconds
after injury through:
a) Vasoconstriction
b) Platelet plug formation
c) Blood clotting
d) Fibrinolysis

29. VASOCONSTRICTION
When platelet come into contact with a
damaged blood vessel, there surface becomes
sticky and adhere to the damaged wall.
Release SEROTONIN which constricts the
vessel thereby stopping blood.

30. PLATELET PLUG FORMATION
They adhered platelet form a clump and
release a substance called ADP (Adenosine
Diphosphate)
Platelet plug formation is complete within 6
minutes of injury.

31. BLOOD CLOTTING
Platelet releases a pre-enzyme called
PROTHROMBIN
It is converted into THROMBIN by clotting
factor X
Thrombin is converted into FIBRINOGEN
Fibrinogen is converted into FIBRIN
When clump of fibrin come together, they
form CLOT

32. FIBRINOLYSIS
 After the clot has formed, the process of
removing it and healing damaged blood
vessel begins.
 PLASMIN breaks down fibrin into soluble
products that are removed by
PHAGOCYTOSIS
 Leading to healing of blood vessels