Spermatophores, Biology

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Spermatophores

Many non-chordates do not release free sperms during copulation. They have a mechanism to bundle and enclose a number of sperms in a sheath usually made of gelatinous material. Such bodies are called spermatophores. Most insects, the centipedes and certain molluscs produce spermatophores. Male centipede emits spermatophores and places it on a web already made. The female picks up the spermatophores and takes it into her genital opening. In many male cephalopods such as Loligo and Argonauta one of the arms gets specialised for the transfer of spermatophore into the females. Such an arm is called hectocotylized arm. The spermatophore, after having been deposited in the female, finally releases the sperms which move into the female ducts or the spermathaca.


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