Which mode of secretion involves complete destruction of the secretory cell?

• A. Holocrine
• B. Merocrine
• C. Apocrine
• D. Endocrine

Answer: (A)

Holocrine secretion is the mode in which the secretory cell is completely destroyed. In this process, the cell fills with the product, undergoes rupture and death, and releases its entire contents along with cell debris into the surrounding space or duct. Because the secretory cell is destroyed, the gland must continually renew its secretory cells from underlying progenitor cells; sebaceous glands in the skin are a classic example.

By comparison, merocrine secretion releases products by ordinary exocytosis without harming the cell, apocrine secretion involves shedding a portion of the cell’s apex with the product while leaving the cell largely intact, and endocrine secretion involves releasing hormones into the bloodstream without destroying the secretory cells.