Bird differs from bat in the absence of

Q. Birds differ from bats in the absence of

Q. Out of the given characters, which ones are present in birds and not mammals?

Q. Note down the differences in the sense of sight of birds like owl and bat and between birds like pigeons and parrots.(2 marks)

Q. Assertion: Bats and whales are classified as mammals.
Reason: Bats and whales have four chambered heart.

Q. Entamoeba differs from Amoeba in the absence of