EVERYDAY SCIENCE

Detailed explanation-1: -Cnidarians have two body forms-polyp and medusa-which often occur within the life cycle of a single cnidarian. The body of a medusa, commonly called a jellyfish, usually has the shape of a bell or an umbrella, with tentacles hanging downward at the margin.

Detailed explanation-2: -There are two basic cnidarian body shapes: a polyp form, which is attached to a surface; and an upside-down free-floating form called a medusa. Some cnidarians change form at different phases of their life cycle, while others remain in one form for their entire life.

Detailed explanation-3: -Cnidarians reproduce both sexually and asexually. Some species can produce both eggs and sperm in the same organism. These organisms are called simultaneous hermaphrodites and release gametes into the ocean in egg-sperm bundles. Some species are also either male or female and produce either eggs or sperm.

Detailed explanation-4: -Cnidarians exhibit two basic body forms called polyp and medusa.

Detailed explanation-5: -Not all cnidarians reproduce sexually, but many species have complex life cycles of asexual polyp stages and sexual medusae stages. Some, however, omit either the polyp or the medusa stage, and the parasitic classes evolved to have neither form.