What is the role of radula in molluscs?
The radula is a file-like rasping organ found in molluscs. It helps in scraping food. It also used for creating depression in rocks.
What is the importance of pneumatic bones and air sacs in Aves?
Give one example each of an animal possessing placoid scales and that with cycloid scales.
Which group of chordates possess sucking and circular mouth without jaws?
Name the animal, which exhibits the phenomenon of bioluminescence. Mention the phylum to which it belongs.
