Do beings of the class Reptilia have direct or indirect development?

Which is the vertebrate class that is considered the first entirely terrestrial?

Do beings of the class Reptilia perform gas exchange in the same way amphibians do?

How is reproduction done in beings of the class Reptilia?

Which is the type of nitrogen waste eliminated by beings of the class Reptilia?

What are examples of a carnivorous and a herbivorous reptile?

How is the circulatory system of reptiles characterized? What is the basic difference between the reptile and the amphibian heart? 

Compared to amphibians what is an example of evolutionary novelty present in beings of the class Reptilia against the loss of water through the skin?

Concerning the maintenance of body temperature how do beings of the class Reptilia classify?

What is an example of a hypothesis which may explain why there is not a big representation of the class Reptilia found in polar regions?