Question

Schizocoelomates and enterocoelomates are
A.Acoelomates
B.Invertebrates
C.True coelomates
D.Echinoderms only

Answer 1

Hint: In animals, the main cavity in the body contains the digestive tract and all organs are called coelom. The coelom is lined with mesodermal epithelium which is derived from the mesoderm. They help in protecting the organs by absorbing shock, facilitate the circulatory system in the body, and play an important role in the immune system of organisms.

Complete answer:
Option A- Acoelomates: The organisms in which the body cavity is not present i.e. they lack a coelom are called acoelomates. For example- tapeworms, planarians, etc.
Option B- Invertebrates: Not all invertebrates possess a coelomic cavity in the body. They may be acoelomic, pseudocoelomic, or true coelomic organisms.
Option C- True coelomates: These are the organisms that contain body cavities and are also known as coelomates. They can be of three types- schizocoelomates, haemo coelomates, and enterocoelomates. Schizocoelomates are the organisms in which coelom is developed from the splitting of mesoderm while enterocoelomates are the organisms in which coelom is developed from the wall of the embryonic gut and haemon coelomates are the organisms in which coelom is not fully developed and is filled with fluid lacking a circulatory system. For example- snails, octopuses, earthworms, etc.
Option D- Echinoderms: Echinoderms are marine animals that have a star-like appearance and are enterocoelomates. For example- sea urchins, sea stars.

Thus, the correct option is option C- True coelomate.

Note:
In some organisms, the coelomic cavity is not wholly lined by mesodermal epithelium and is called pseudocoelomates. For example- roundworms. A coelomic cavity can be formed by two processes i.e. Schizocoely and enterocoely.