Question

The life of the erythrocytes in mammalian blood is about
A. 120 days
B. 150 days
C. 190 days
D. 180 days

Answer 1

Mammalian RBCs or erythrocytes are produced by a process known as erythropoiesis. They are the most common type of blood cells and function mainly as oxygen transporters. The life span of the cells varies according to the conditions, which are different in infants, normal healthy individuals, and people with chronic diseases.

Step by step answer: Erythrocytes or RBCs are continuously produced in the Red Bone Marrow of large bones When the RBCs mature, it stays in the blood circulation for a period of 120 days in a normal individual. With the end of their lifespan, the cells are removed from the circulation system. The cells are then destroyed in the spleen, liver, and bone marrow out of which the spleen is known as the “Graveyard of RBCs”, through homeostatic mechanisms such as phagocytosis. The most common cause of the death of these cells is the wear and tear caused due to the extensive circulation through the blood vessels such as veins, arteries, and capillaries leading to the cells attaining senescence.
Thus, the correct option is A, i.e., The life span of mammalian erythrocytes is 120 days.

Note: A typical mammalian RBC is biconcave discoid in shape and does not possess a nucleus, it accommodates a maximum amount of haemoglobin in each cell. The lifespan of RBCs gets decreased in the presence of various diseases such as kidney injury, sickle cell anemia. The haemoglobin present in the RBCs is responsible for the transport of the major proportion of oxygen.