Integument in Different Classes of Chordates | Zoology

The fundamental structure of skin in all the vertebrates is the same but there are certain variations in different classes. 1. Protochordata: In Branchiostoma the skin is simple without keratin. The epidermis is single layered made of tall or columnar cells. These are ciliated in Balanoglossus. Epidermis has numer­ous unicellular gland cells which secrete a thin cuticle in Branchiostoma. Dermis [...]