Blood is a liquid connective tissue that contains cellular elements (blood cells) and fluid matrix (plasma). Blood helps in the transportation of different substances throughout the body. Study of blood and its disease is known as Hematology.

1. Blood
Amjad KhanAfridi
Chapter # 04

2. • Blood is a liquid connective tissue that
contains cellular elements (blood cells) and
fluid matrix (plasma).
• Blood helps in the transportation of different
substances throughout the body.
• Study of blood and its disease is known
as Hematology.

3. Composition of Blood:
• Cellular substances (Blood cells) : 45%
• (RBC 44%) & buffy coat containing platelets
& WBC 1% )
• Plasma: 55% (Of total: 91% liquid & Solid
9%).

4. PLASMA 55%
1%
44%
Water
Ions
Proteins
Nutrients
Wastes
Gases
Platelets
White Blood Cells
Red Blood Cells

5. Blood cells:
• Erythrocytes or Red blood cells (RBC)
• Leucocytes or White blood cells (WBC)
• Platelets or Thrombocytes

6. Plasma
Plasma = (Blood- Blood cells)
• It is the liquid part of blood and is composed
of 90-92 % water, 7-8 % plasma protein and 1-
2% other substances (glucose, amino acids,
electrolytes, ammonia, enzymes, hormones,
vitamins, etc).

7. Plasma proteins:
• Helps in maintaining osmotic pressure,
coagulation of blood, viscosity, blood pressure,
defensive action, transport of gases.
• The solvent property of water helps in transport of
nutrients as well as metabolic wastes from one
part of body to another part
• Liver produces about 30gm of plasma protein
each day.

8. Types
• Albumin: (58-60%) most abundant, main
function is to maintain plasma osmotic pressure
(Oncotic pressure).
• Globulin: (36-38%) – It is important
for immunoglobulin. The most important
globulin is gamma globulin.
• Fibrinogen: (3-4%) – It helps in blood clotting.

9. • Electrolytes- Na, K, Cl, Ca, HCO3
• Nutrients- Glucose, amino acids, fatty acids,
Vitamins & minerals.
• Gases: Oxygen, Carbon dioxide, Nitrogen.
• Waste products: Urea, Uric acid, Creatinine.

10. Properties of Blood:
• Amount: : 7-9% of total body weight; 79ml/kg
• Blood volume: 5-6 liters
• Viscosity: (3.5-5.5) times more than water.
• Specific Gravity: 045-1.065
• PH:3-7.4 (slightly alkaline)
• Venous blood has low pH than the arterial blood
as venous blood has more CO
• Temperature- 380C (100.4F)
• Osmotic pressure– 25 mm Hg.
• Color: red, due to haemoglobin

11. Functions of Blood
i. Transportation:
• transport of O2 from lungs to body tissue and CO2
from tissue to lungs
• transport of wastes of cellular metabolism from body
tissue to kidney, liver or sweat gland and eventually
removal out of body
• Transport of hormones, enzymes, other chemicals
throughout the body.
• Nutrients absorbed in the digestive tract, such as
glucose, amino acids, vitamins, minerals etc and are
circulated to all body tissues.
• Waste products of the tissues, such as urea and
creatinine, circulate through the kidneys and are
excreted in urine.

12. ii. Regulation (Homeostasis):
• regulate body temperature
• distribution of heat throughout the body
iii. Balance
• Maintaining electrolyte balance
• Maintain acid base balance
iv. Protection:
• protect body from harmful microorganisms, by
WBCs, protein and antibody
• develop immune response (plasma protein).

13. Thank You
9
th
December,
2021