In this article we will discuss about the sense organs in aurelia, explained with the help of a suitable diagram. i. Sense Organs: The sense organs include the olfactory pits, the ocelli and the tentaculocysts or rhopalia. ii. Olfactory Pits: Two, lined with sensory epithelium—one lie on the ex-umbrella and the other in the sense club. These are chemoreceptors and [...]
In this article we will discuss about the structure of aurelia, explained with the help of a suitable diagram. a. The body consists of a gelatinous disc with a slightly convex ex-umbrella (Fig. 20.17) and bears a four-cornered mouth on a short manubrium guarded by four oral arms at the centre of the sub-umbrella. b. The margin bears a [...]
In this article we will discuss about the classification of phylum cnidaria. Classification of the Phylum Cnidaria: 1. The Cnidaria are radially symmetrical in oral-aboral axis (biradial in some Anthozoa); no head and segmentation; simplest of all metazoans with a low grade of tissue formation. 2. The body wall is composed of two principal layers, an outer epidermis (ectoderm) and [...]