The _______________ of a feather is a structure that typically emerges from the skin. 

The site of gas exchange between the mammalian lungs and the bloodstream is the

The lungfishes

The site of gas exchange between the mammalian lungs and the bloodstream is the

The following animal is a member of what class? 

Which of the following is justification for resorting to war?

Which of the following can lead to the process of speciation? 

This is a doctrine holding that justice requires equal distribution of goods and social benefits among all persons.

Which of the following scale types would NOT be found in Actinopterygii? 

Which of the following scale types would NOT be found in Actinopterygii?