Question

40. Which is not correct for sponges ?
(a) Internal fertilisation
(b) External fertilisation
(c) Gemmule formation
(d) Gametes are formed from epidermal cells
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Answer 1

Answer:

•Sponges are hermaphrodite as both male and female gametes are produced by the same individual. Fertilisation is internal as the sperm and ovum gets fused inside the body of sponge.

•Gemmules are the asexual reproductive bodies that are formed by endogenous budding in all freshwater and some marine sponges.

•In sponges, gametes are formed from archaeocytes. Archaeocytes are undifferentiated embryonic amoebocytes with blunt pseudopodia and show totipotency. These cells are found in mesenchyme which is the inter connecting proteinaceous matrix between the outer and inner body wall layers of sponges.  

Hence, option B is incorrect as external fertilisation is not found in sponges.

So, the correct answer is 'External fertilisation'.

Explanation:

Answer 2

option d is correct✅✅✅✅