Question

Which of the following cells are useful for feeding in sponges?

• A. Thesocytes
• B. Collar cells
• C. Pinacocytes
• D. Sclerocytes

Answer 1

The correct option is B Collar cells

Thesocytes are present in the sponges for the purpose of food storage.

Pinacocytes are involved in the maintenance of the structure and size of sponges.

Choanocytes (also known as "collar cells") are cells that line the interior of sponges. These are ovoid cells with one end embedded in the mesophyll and the other exposed. The collar cells have a sticky, funnel shaped collar and a hairlike whip at the exposed end which is called a flagellum. They beat their flagella back and forth to force water through the sponge. The water brings in nutrients and oxygen, while it carries out waste and carbon dioxide. The microvilli which are adjacent to the flagellum are connected to each other by delicate micro-fibrils, forming the fine filtration device for straining food particles from the water.

So, the answer is B.