Question

UPSC Prelims 2021 Question:

Which one of the following is a filter feeder?

1. Catfish
2. Octopus
3. Oyster
4. Pelican

Answer (Detailed Solution Below)

Option 3: Oyster

Detailed Solution

Explanation:

Filter feeders are animals that get their food by moving water through a structure that acts as a sieve.
Oysters are filter feeders. They draw water over their gills by beating Cilia. Suspended plankton and non-food particles trap in the mucus of a gills and from there get transported to the mouth of Oysters.

Therefore, option (3) is the correct answer.

Subject: Environment | Ecology

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