Question

Characteristic features of organisms belong to the phylum Mollusca are:
i. Soft body
ii. Jointed legs
iii. Presence of internal/external shell.
iv. Gills as the organ of respiration
v. Presence of mantle and mantle cavity
vi. Distinct body segmentation

• A. i, ii, iii, iv
• B. i, ii, iii, v
• C. ii, iii, v, vi
• D. i, iii, iv, v

Answer 1

The correct option is D i, iii, iv, v

The salient features of phylum Mollusca are:

i. Soft body.
ii. Shell is present, may be internal (e.g. sepia) or external (e.g. snail).
iii. Presence of Mantle and mantle cavity. The body covering folds onto itself leaving a space between this fold and body. This cavity is known as mantle cavity and its covering is the Mantle. Both help in respiration.
iv. Presence of Radula; it is the masticating organ present in the buccal cavity, just after the mouth.
v. Presence of broad muscular foot which is seen variously modified according to the habitat of animal.