Archive | Deuterostomes

Coelomates are animals that have internal body cavities, or coeloms. Humans are coelomates, since we have an abdominal cavity containing digestive organs, some of the excretory and reproductive organs, and a thoracic cavity that contains the heart and lungs, Coelomates also form a variety of internal and external skeletons. External skeletons and coeloms appeared during the Cambrian- Ordovician time. These [...]