Question

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

Answer 1

Hint: Coelom is the body cavity present in most of the animals.
It is mainly found in between the intestinal and body wall.
It acts as a protective cushion for their internal structure.
The coelom helps in the movement of the internal organs and grows independently of the outer layer of the body wall.

Complete step-by-step answer:
The coelom is the primary body cavity present in most of the animals.
It is placed inside the body to surround and it also contains the digestive tract and other organs.
In some animals, it is lined with mesothelium whereas In other animals, such as molluscs, it remains undifferentiated.
In the past, and for practical purposes, coelom characteristics have been used to classify bilateral animal phyla into informal groups.
There are three types of coelom present such as:
1. Acoelomate: Coelom is absent.
The blastocoel is completely occupied by mesoderm.
2. Pseudocoelomate: True coelom is not present.
Because the blastocoel is partly or fully filled by mesodermal cells.
3. Eucoelomate: Animals that have a true coelom.
The true coelom is divided into two types-
1. Schizocoelom
2. Enterocoelom.
They are divided on the basis of their ways in which true body cavity or coelom originates in different animals.
 Schizocoelom originates from the mesodermal split.
Example: Organisms belonging to the Phylum Annelida, Mollusca, and Arthropoda.
Enterocoelom originates from out pocketing of the embryonic gut (endoderm).
This type of body cavity is formed by out pocketings of the primitive gut that break off and form the coelom.
Example: Organisms belonging to the Phylum Echinodermata and Chordata.

So, the correct option is option C. True coelomates

Note: A coelom can absorb shock or provide a hydrostatic skeleton.
It can also support an immune system.
The coelom allows muscles to grow independently of the body wall.
This feature can be seen in the digestive tract of water bears.