The sperm They are usually cells, much smaller than the eggs and are structured to allow maximum displacement efficiency, which increases their chance of reaching the egg.

They are small, elongated, hydrodynamically shaped cells with a long tail that is used for propulsion.

Scheme of the human sperm

Although the vast majority of animal sperm are flagellated, there are sperm without flagella. This is the case of sperm of nematodes, vermiform animals whose best known representative is the roundworm (Ascaris lumbricoides), a parasite of the human intestine.

Sperm vary greatly in size and shape among different species.

1- Snail sperm (gastropod)
2- Ascaris sperm (nematode)
3- Salamander sperm (amphibian)
4- Frog (amphibian) sperm
Rooster sperm (bird)
6- Rat sperm (mammal)
7- Lamb sperm.
8 - Man sperm