Question

Characteristic features of 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 habitat of animal.