Question

Is the white blood cells disposing of a worn-out red blood cell carried out through endocytosis, phagocytosis, or both?

Answer 1

Phagocytosis is a specific form of endocytosis.

Explanation:

Erythrocytes have an average life span of 120 days. On ageing the enzyme activity of erythrocytes reduces drastically and they become spherical and sluggish.

Macrophages are a type of large white blood cells. They exist freely or fixed in the lining of the blood vessels of the spleen, liver and bone marrow.
Macrophages engulf the worn out erythrocytes through the process of phagocytosis.

The erythrocytes are then broken down and their protein, amino acid and iron components are re used by the body. The remaining unwanted cell debris is destroyed within the macrophage.