Question

Organisms belonging to phylum Mollusca have a rasping organ called radula for feeding. What does Rasping mean?

Answer 1

Hint: Mollusca are the sluggish invertebrates which have soft fleshy body. They are triploblastic coelomate with bilateral symmetry. They have a specialises organ called radula which is similar in function to that of tongue. It is present in the mouth of the organism.

Complete answer:
We know that Mollusca are soft bodied sluggish animal who have a definite mouth for feeding. They have a unique structure called the radula which helps the organism to feed. Radula is similar to that of tongue. It is a chitinous ribbon like structure which contains minute tooth. It is used for rasping of the food before it enters the food pipe. The radula is used for feeding both plants based and animal-based food. The arrangement of radula varies from one group to another.

Rasping means scrapping and cutting. The Mollusca have a ribbon like structure, the radula. These radulae have rows of minute teeth that is used for scraping and cutting of the food. The mollusca rasps small diatoms and also algae attached to the rocks.

Note: The radula comprises of elastic membrane that can be a single tongue or two. The teeth present can bend in the sideways direction. The tooth has a base, shaft and a cusp and are interlocked tightly with the neighbours. The teeth are arranged in the manner of central, on each side lateral and beyond that is marginal. The shape of the teeth depends on the feeding habits.