Question

Identify the correct statement about the organisms Spongilla, Leech, Dolphin, and Penguin.

• A. Leech is fresh water while all others are marine.
• B. Spongilla has special collared cells called choanocytes while it is not found in the other three.
• C. All are bilaterally symmetrical.
• D. Penguin is homoiothermic while the remaining three are poikilothermic.

Answer 1

The correct option is B Spongilla has special collared cells called choanocytes while it is not found in the other three.

A. Spongilla is a freshwater sponge, Leech occurs both in freshwater and marine environment and Dolphin and Penguin are marine.

B. Choanocytes or collar are the characteristic feature of phylum porifera i.e. sponges. Since Spongilla is a sponge, hence, choanocytes are present only in Spongilla and not the other three.

C. Spongilla is asymmetrical while other three are bilaterally symmetrical.

D. Spongilla is a sponge and doesn't have blood. Dolphin and Penguin are homoiothermic and Leech is poikilothermic.

Hence, statement B is correct.

So, the correct answer is 'Spongilla has special collared cells called choanocytes while it is not found in the other three'.