Question

Name the respiratory organ of phylum mollusca.

Answer 1

Phylum Mollusca:

1. Mollusca is the second-largest phylum of invertebrates after Arthropoda, and its members are known as molluscs or mollusks.
2. All molluscs breathe through gills known as ctenidia (comb-gills, due to their comb-like form). It helps in the exchange of respiratory gases.
3. This respiration organ is diminished in terrestrial molluscs, although respiration occurs in the pallial cavity. As a result, it is also known as the snail's respiratory cavity.
4. Example: - apple snails (Pila), cuttle fish (Sepia), devil fish (Octopus) and mussels.