Question

Whose secretion forms the pearl?

• A. Prismatic layer
• B. Columnar epithelial cells of mantle
• C. Ciliated epithelial cells of mantle
• D. Connective tissue of mantle

Answer 1

The correct option is B Columnar epithelial cells of mantle

The principal causative factor in pearl formation in a pearl oyster is the presence of a nucleus. It can be of organic or inorganic origin, such as parasites adults or larvae, molluscan eggs, decaying parts of plants, sand grains, epithelium or blood cells of the same animal, etc. These tiny particles or organisms enter the oyster when the shell valves are open for feeding and respiration. These foreign bodies may become embedded between the shell and mantle. In response to this stimulus, the foreign body is invaginated by the outer columnar epithelial cells of the mantle and a pearl-sac is formed around it.

Therefore, the correct answer is option B.