Question

Explain the general characteristics of phylum Mollusca.

Answer 1

Phylum Mollusca:

It is the second-largest phylum of the kingdom Animalia. These are aquatic and terrestrial animals.

Characteristics:

1. The animals possess a soft and unsegmented body.
2. The body is triploblastic, bilaterally symmetrical, and coelomates.
3. The body is divided into a distinct head, muscular foot, and visceral hump.
4. The head consists of eyes, mouth, and tentacles.
5. The visceral hump is covered by a soft and spongy layer of skin called the mantle.
6. The foot present is used for moving around.
7. The body is covered by a calcareous shell.
8. The shells may be of various shapes.
9. The coelomic cavity is reduced.
10. There is little segmentation.
11. It includes apple snails (Pila), cuttlefish (Sepia), devilfish (Octopus) and mussels.