Question

1. what are setae?

setae are specialized digestive glands that secrete enzymes.
setae are the flagella found on the choanocytes of sponges.
setae are tentacles that contain stinging cells in cnidarians.
setae are bristles found on the segments of annelids.

Explanation:

To determine the correct answer, we analyze each option:

• The first option is incorrect because setae are not digestive glands.
• The second option is incorrect as choanocytes of sponges have flagella, not setae.
• The third option is incorrect because tentacles with stinging cells in Cnidarians are called cnidocytes - containing tentacles, not setae.
• The fourth option is correct: Setae are bristle - like structures found on the segments of Annelids (e.g., earthworms) and they help in locomotion.

Answer:

D. Setae are bristles found on the segments of Annelids.