Question

Unlike amphibians, reptiles 

A. have lungs to oxygenate blood.B. use single-loop circulatory system.C. have a closed circulation system in which blood circulates entirely within blood vessels.D. have ventricles that are further divided to lessen mixing of oxygen-rich and oxygen-poor blood.

Answer 1

C. have a closed circulation system in which blood circulates entirely within blood vessels. Most reptiles have a closed circulatory system compared to amphibians' double circulation system. Some reptiles possess a four chambered heart and some three chambered.