Animals that change greatly as they mature are said to undergo.

Animals that change greatly as they mature are said to undergo metamorphosis. Metamorphosis is actually a biological process by which an animal develops after birth and then there is a sudden or abrupt change in the animal as it reaches adulthood. One of the best example of metamorphosis can be found in the development of a tadpole to a frog. 

Sorry its not enough info

Carbon dioxide is the correct answer