The upcoming discussion will update you about the differences between Cartilaginous and Bony Fishes. Difference # Cartilaginous Fishes: 1. Cartilaginous fishes are mostly marine. 2. The mouth of cartilaginous fishes is ventral. 3. The external nares are ventral. 4. The scales of cartilaginous fishes are Placoid. 5. In cartilaginous fishes, operculum is absent except chimaera. 6. Caudal fins are heterocercal [...]
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 [...]