Blood – Composition & Functions
Q 1. What is the composition of blood?
Blood is a liquid tissue that constitutes 7% of the total body weight. It is made up of four main components: plasma, erythrocytes (red blood cells), leukocytes (white blood cells), and thrombocytes (platelets).
- Plasma: 55% of blood, a clear liquid that carries blood cells, nutrients, gases, and waste products.
- Erythrocytes: 45% of blood, carry oxygen from lungs to body tissues.
- Leukocytes: 1% of blood, fight infection and disease.
- Thrombocytes: 1% of blood, aid in blood clotting.
Q 2. Describe the function of blood.
Blood performs several vital functions:
- Transportation of gases: oxygen to body tissues and carbon dioxide from body tissues to lungs.
- Transportation of nutrients: glucose, amino acids, and fats from digestive system to body tissues.
- Transportation of waste products: urea, creatinine, and other waste products from body tissues to kidneys for excretion.
- Regulation of body temperature.
- Maintenance of pH balance.
Q 3. Define serum.
Serum is the component of blood that remains after clotting and removal of cells, fibrinogen, and other clotting factors. It is the liquid portion of blood that contains water, salts, sugars, fats, and proteins.
Q 4. Explain the difference between serum and plasma.
Plasma and serum are both liquid components of blood, but they differ in their composition:
- Plasma: contains all the components of blood, including clotting factors and fibrinogen.
- Serum: obtained after clotting and removal of cells, clotting factors, and fibrinogen, leaving behind only the water, salts, sugars, and proteins.
Key points to understand:
- Blood composition: plasma, erythrocytes, leukocytes, and thrombocytes.
- Functions of blood: transportation of gases, nutrients, waste products, regulation of body temperature, and maintenance of pH balance.
- Serum: obtained after clotting and removal of cells and clotting factors.
- Plasma: contains all the components of blood, including clotting factors and fibrinogen.