In this article we will discuss about the General Characters and Classification of Phylum Cnidaria. General Characteristics of Phylum Cnidaria: Some of the important General Characters of Phylum Cnidaria are listed below: 1. Habitat: All are aquatic and are mostly marine, except a few like Hydra, are fresh water. 2. Body Form: Body form varies considerably. Many colonial cnidarians like [...]
In this article we will discuss about the meaning and classification of phylum cnidaria. Meaning of Phylum Cnidaria: The phylum Cnidaria (coel=hollow; enter on—gut) includes the simplest of the cellular animals or xnetazoa. The coelenterate body is a two-layered sac, opening to the exterior by a single aperture called mouth. The mouth is surrounded by a number of tentacles and [...]
In this article we will discuss about the histological organisation of Cnidarians. 1. Ectoderm: In most cases it is distinctly cellular. Presence of ciliated ectoderm in larval cnidarians is usually seen. The cellular ectoderm is mainly composed of the supporting cells, called the Epitheliomuscular cells. They are usually cuboidal or columnar in shape. They may be thin and flattened (exumbrellar [...]