In this article we will discuss about the integument of various chordates:- 1. Fishes 2. Amphibians 3. Reptiles 4. Birds. 1. Fishes: In bony fishes, dermal scales do not actually pierce the epidermis, but they are so close to the surface they give the impression that the skin is hard (Fig. 2.4). The epidermal covering includes a basal layer of [...]
In this article we will discuss about the digestive systems of Branchiostoma and Ascidia. Digestive System of Branchiostoma: In Branchiostoma, the digestive and the respiratory systems are intimately associated with one another. The pharynx is a very elaborate structure which occupies more than half of the total surface area of the body. The food particles are filtered from the respiratory [...]
In this article we will discuss about:- 1. Integument in Mammals 2. Horns in Mammals 3. Antlers. Integument in Mammals: Epidermis is divided into five layers; from outside these are as follows (Fig. 2.20): (i) Stratum corneum: This is the outermost keratin layer. Cell boundary is indistinguishable and nucleus is absent. This layer is thick in the palm and sole [...]