Question

Earthworms are hermaphrodites and reproduce primarily by

• A. self-fertilisation
• B. cross-fertilisation
• C. asexual reproduction
• D. all of these

Answer 1

The correct option is B cross-fertilisation

Earthworms are bisexual in nature. They have the sex organs of both male and female in the same organism (hermaphrodites). But they are capable of cross-fertilisation because the spermatozoa and ova mature at different times in the same earthworm. In cross- fertilisation, one of the earthworms deposits the sperms in the genital pouch of another earthworm. The earthworm which deposits sperms becomes the male earthworm and the latter becomes the female earthworm.
Fertilization within the same organism is called self-fertilization. For example in some bisexual flowers self fertilisation occurs wherein the male gamete and female gamete of the same flower fuses.
A type of reproduction which does not involve the fusion of gametes is called asexual reproduction. Budding, fission are various types of asexual reproduction.