In this article we will discuss about Sea Anemone:- 1. Habit and Habitat of Sea Anemone 2. Structure of Sea Anemone 3. Nutrition 4. Histology 5. Nervous System 6. Reproduction 7. Development. Contents: Habit and Habitat of Sea Anemone Structure of Sea Anemone Nutrition in Sea Anemone Histology of Sea Anemone Nervous System of Sea Anemone Reproduction in Sea Anemone [...]
The relationship between metagenesis and polymorphism has raised the question—is metagenesis an outcome of polymorphism or has it lead to the emergence of polymorphism? A discussion on the existence of different grades of metagenesis in cnidarians will help us to find a logical answer. Gradations of Metagenesis: Four different forms of life-histories are seen in the cnidarians which exhibit a [...]
The following points highlight the two main types of polymorphic variabilities in Siphonophora. 1. Modifications of the Polyp: A. Gastrozooids or Trophozooids or Nutritive Zooids: Characters: 1. It is like a typical polyp (Fig. 12.34A,B). 2. Each gastrozooid is a cylindrical and funnel-shaped body with a large mouth. 3. Presence of a well-formed coelenteron. 4. A single long contractile and [...]