Short notes on the structure of RBC

These are commonly called the red blood corpuscles (R.B.C). As the name indicates they are scarlet red in colour due to the presence of an oxygen carrying pigment called Hemoglobin. The shape of the RBCs varies in different groups of animals. In frog the RBC is biconvex and nucleated; the same is the condition in fishes, rep­tiles and birds. The RBCs of mammals are circular and biconcave and do not have any nucleus. The central part of the RBCs is thinner and helps in flexibility.

The size of the human RBCs is 7 to 8 mm in diameter. In human beings on an average there are about 4 to 5 million RBCs per cubic mm of blood. The RBC’s are formed in bone marrow by cells called megaloblasts. Re­duction in the number of RBCs causes anemia.