Reptiles are ectotherms and cannot raise their body temperature above that of the environment.
<span>Unidirectional flow in the heart is ensured because the heart contains valves that prevent backflow.
These valves keep the flow of the heart going in one direction (hence the name "unidirectional").</span>
Light aka the sun I know for a fact
Answer:
I believe so. The shapes and ect. of bones determine how animals are evolving and how they will evolve more.
Explanation:
I hope this helps by the way. I'm not completely sure tho.