Question

Describe in detail the composition of human blood.

Answer 1

Hint: Blood is the red-colored fluid which flows in blood vessels. RBC is the major component of the blood, which carries sufficient oxygen all over the body and it has a special pigment.

Complete Answer:
The blood has two components, i.e., plasma and blood cells or corpuscles. RBCs and WBCs are living, while plasma and platelets are non-living.
1) Plasma: Plasma is the nonliving, liquid part of the blood. It forms nearly 55 percent of blood. Plasma performs several functions like transportation of nutrients, hormones, and proteins to the parts of the body that need it. The plasma also regulates the body temperature and helps in removal of waste.

2. Blood Corpuscles or blood cells: They constitute 45 percent of the blood.
(a) Red blood Corpuscles (RBCs) or erythrocytes: They contain a red colored pigment called haemoglobin. It binds with oxygen to form oxyhaemoglobin, which transports oxygen to all the body cells.The average lifespan of RBCs is about 120 days.
(b) White blood Corpuscles (WBCs) or Leukocytes: white blood cells are colorless due to the lack of haemoglobin. It fights against germs and also provides immunity against infection. They are also called soldiers of the body. The life span of WBCs ranges from 13 to 20 days. WBCs are broadly classified into two main kinds: granulocytes and agranulocytes. Granulocytes include neutrophils, basophils and eosinophils while lymphocytes and monocytes are the agranulocytes.
(c) Platelets or thrombocytes: Platelets are very tiny cells which help in the clotting of blood.

Note: Blood circulates through our body and delivers essential substances like oxygen and nutrients to the body's cells. Blood helps in regulating body temperature and protects the body against infection.