Midwife toad is another name for

Which of the following is a characteristic of $Amphibia$?

In this class,the cloaca serves as a common opening for the digestive,urinary,and reproductive tracts.

Statement $X$: The skin of amphibians acts as a respiratory organ.
Statement $Y$: Amphibians lack an exoskeleton and have moist skin.

Which class is the first class of vertebrates?

Annual migration does not occur in the case of