Question

Write any two foot modifications in Mollusca.

Answer 1

The visceral mass is present above the foot, in the visceral hump. This includes digestive, nervous, excretory, reproductive, and respiratory systems. Mollusk species that are exclusively aquatic have gills for respiration, whereas some terrestrial species have lungs for respiration. Additionally, a tongue-like organ called a radula, which bears chitinous tooth-like ornamentation, is present in many species, and serves to shred or scrape food. The mantle (also known as the pallium) is the dorsal epidermis in mollusks; shelled mollusks are specialized to secrete a chitinous and hard calcareous shell.





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Answer 2

The molluscs are characterized by a muscular foot present on the ventral (under) side of the body, which is modified to perform various purposes in different classes.

Let's discuss two such modifications here.

1. Foot for locomotion

Molluscs that live in terrestrial environment typically have a large flat creeping lobe or sole with numerous mucus-producing gland cells.  

For example: Gastropods

1. Foot for burrowing

In some molluscs that live in soft bottom habitat, the foot becomes modified to act as burrowing organ.  It is usually a laterally compressed and blade-like with the anterior or front part acts as a burrowing organ.

For example: Bivalves

Know more:

Examples of molluscs without shell. ?

https://brainly.in/question/91708

Scales of fish and shells of molluscs are homologous or analogous organs

https://brainly.in/question/2664947