Multiple choice

Regarding the reproduction in sponges, which of the following statements is INCORRECT?

  1. In the sponges the sperm are produced by collencytes.

  2. During spawning, sperm burst out of their cysts and are expelled via the osculum.

  3. Gemmules are aggregates of sponge tissue and food.

  4. Only a sponge fragment containing both collencytes and archeocytes will regenerate.

  5. Freshwater gemmules may also include phytosynthesising symbionts.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Most sponges are hermaphrodites (function as both sexes simultaneously), although sponges have no gonads (reproductive organs). Sperm are produced by choanocytes or entire choanocyte chambers that sink into the mesohyl and form spermatic cysts while eggs are formed by transformation of archeocytes, or of choanocytes in some species.

Keep practicing — related questions