Young Hydra shortly after emerging from an egg 插畫檔

Tentacles: The finger-like projections at the top are the tentacles. In these young specimens, they are just beginning to develop and are fewer and shorter than those of an adult.Body Column: The long, cylindrical part of the animal. It is composed of two main cell layers (ectoderm and endoderm) separated by a jelly-like substance called mesoglea.Basal Disc (Foot): Though not labeled, the bottom of the column is where the Hydra attaches itself to surfaces like underwater plants or rocks.