Information on Hydras 1

Hydra Profile

Hydra are small-bodied freshwater polyps with a tube-like body and a mouth surrounded by tentacles. The hydra's simple tubular body with its crown of tentacle has earned it a place in every elementary textbook of zoology and made it the object of many detailed studies.

The hydra is one of a few freshwater cnadarians. The body of a hydra is a bag whose wall is made up of two layers of cells separated only by a very thin layer of non-cellular material. Hydra usually have 5-6 hollow tentacle, but may have up to 12. These tentacles surround the mouth. The other end of the body is a basal disc which normally anchors the hydra by a sticky secretion. Both tentacles and body are very extensible, for the bases of many of the cells are drawn out as muscle fibers. The nervous system is extremely simple, made up of only a network of nerve cells. There is no brain of any sorts.

Habitat

Hydras are primitive marine animals found in ponds.

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