Given a scientific question, generate a correct answer to it.

What is the process of the transfer of pollen from an anther to a stigma in angiosperms called?
pollination

Carboxylic acids have an acidic hydrogen atom, but esters do not. what do esters have in place of an acidic hydrogen atom?
hydrocarbon group

In mammals, air is warmed and humidified in what?
nasal cavity