Biology : Animal Kingdom

Fill up the blank spaces appropriately.                                                                          

On a morning  walk  with your friend you came across an animal which looks like a snake. But on watching it closely, your friend says it is an earthworm. What helped him in identifying it as an earthworm?                                                                                                             

1.In order to eradicate mosquitoes Housing colony members were asked to keep the surroundings dry, not to let water standing any where and cover the drainage. It was found that the strategy worked and there was decline in the number of mosquitoes.What according to you is the reason for the decline in the number of mosquitoes.?

Ravi’s younger brother of class III stated that bats are like birds as they are able to fly.
How will you contradict him and make him understand that bats are mammals and not birds?

What is metagenesis? Mention an example which exhibits this phenomenon.

What is the role of radula in molluscs?

Identify the phylum in which adults exhibit radial symmetry and larva exhibit bilateral symmetry.

What is the importance of pneumatic bones and air sacs in Aves?

Which group of chordates possess sucking and circular mouth without jaws?

Give one example each of an animal possessing placoid scales and that with cycloid scales.