Question

The main function of interstitial cells is
a. Excretion
b. Defence
c. Replenishment of lost cells
d. Digestion

Answer 1

Hint: The interstitial cells of coelenterates helps in formation of multipotent stem cells. Here male secrete testosterone hormone, which regulates the sexual cycle of male. The interstitial cells of the alimentary canal help in peristalsis.

Complete answer:
The interstitial cells or Leydig cells are found in male testes. They are attached to seminiferous tubules. These cells are responsible for the secretion of testosterone hormone in the presence of Luteinizing Hormone (LH), which is secreted by the anterior lobe of the pituitary gland. These cells contain a large nucleus, eosinophilic cytoplasm and polyhedral shape. They also contain a large amount of smooth endoplasmic reticulum (SER) and mitochondria.

The interstitial cells are also present in the alimentary canal of human beings, which are known as Interstitial cells of Cajal. These cells are present in the wall of the alimentary canal and facilitate communication between the smooth muscle of the alimentary canal and nervous system. When the nervous system sends signals to the interstitial cells of Cajal that a person has eaten the food, the interstitial cells of Cajal start beating rhythmically. They also stimulate smooth muscles of the alimentary canal for rhythmic contraction and relaxation. This process results in the peristalsis through which cells propels food along the entire length of the alimentary canal.

The interstitial cells are also present in Hydra, which is a member of Phylum Coelenterata. In these animals, interstitial cells form a multipotent stem cells, which produces nerve cells, digestive cells, gametes and cnidoblast during asexual growth of individual. These cells contain abundant free ribosomes and few other cell organelles.

The interstitial cells help in production of testosterone hormone, peristalsis of alimentary canal and formation of multipotent stem cells.

Hence, The correct answer is option (C).

Note: The peristalsis is the rhythmic contraction and relaxation of the alimentary canal that moves food to different organs of the alimentary canal.
The cnidoblast contains a thread-like, coiled stinging cell, which helps to capture the prey and anchorage.