axoneme

Spermatozoon and Its Structure

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A spermatozoon is a highly specialized, free swimming, actively motile cell which measures about 60 µm in length. The spermatozoon is made up of three parts. They are: a head, a neck and a tail or principal piece. Head is piriform in shape and measures 4 µm in length. It is derived from the nucleus, … Read more

Differences between prokaryotic and eukaryotic cell

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S.N Prokaryotic cell Eukaryotic cell 1. An organized nucleus is absent. An organized nucleus is present. 2. Nucleus is represented by packed mass of DNA fibres, which lacks nuclear membrane and nucleoli. It contains chromatin network, nuclear membrane and nucleoli. 3. DNA is naked i.e. it lacks protein association. DNA is covered with histone proteins … Read more