In this article we will discuss about the Structure of a Typical Fish. Fishes are cold blooded animals, typically with backbone, gills and fins. The body of a typical fish comprises the head, trunk and tail. The head bears two eyes, with well developed nictitating membrane, two internal ears, two nostrils which are closed internally (except in lung fishes) and [...]
The below mentioned article provides biology notes on Phylum Hemichordata. (Gk. hemi- half, chordate- notochord) Due to some similarities with chordates, some workers considered Hemichordata as a subphylum under phylum chordata. But, on grounds of its general organization, recent scientists, like Vander Horst (1939), Dawyd off (1948), Marcus (1958) and Hyman (1959), have given it the status of a phylum [...]
The below mentioned article provides biology notes on Eucoelomates. The animals which possess true coelom are called eucoelomates or coelomates. The true eucoelomates is a body cavity which arises as a cavity in embryonic mesoderm. In this case, the mesoderm of the embryo provides a cellular lining, called coelomic epithelium or peritoneum, to the cavity. The eucoelomates is filled with [...]