Question

Given figure of Hydra shows its reproductive structures and manner of fertilisation.

Observe and answer that why is it not showing self fertilisation?

• A. Distance between testis and ovary is more
• B. Sperms do not swim downwards
• C. Ovary matures earlier than testis
• D. Testis matures earlier than ovary

Answer 1

Answer: (D)

Cross fertilisation occurs in Hydra. The testis matures earlier than ovary. The spermatozoa released from the testis of one Hydra swim in water with their tails and finally come into contact with the ovum of another Hydra. Ovum lives only for a short time after it is exposed. During this period, fertilisation must take place. Thus, given figure is not showing self-fertilisation but cross-fertilisation.