The left ventricle is responsible for pumping oxygenated blood throughout the entire body, which requires a lot of work and pressure, hence why it is super thick.
A group of atoms bonded together
B. because natural selection is when the environment causes an organism to evolve, the climate becoming colder and wetter would likely overtime cause the rats to have thinner hair and have skin that can handle staying wet more
Hemlck looks at question
Starts typing.
Sees "Elementary School"
Delete. The best thing to do is to ask your parents about this question as its not best suited for the internet. Since it is a biology question though, it depends on the species.
If its human, it would be... you know... just ask your parents
