Imagine you are a fish stranded in a small pool of water on land. The pool of water occasionally almost dries up. What challenges does life on land present? What are 2 key changes in vertebrate evolution from aquatic to terrestrial habitats?

the oxygenated blood then leaves the lungs through pulmonary veins, which return it to the left heart, completing the pulmonary cycle. this blood then enters the left atrium, which pumps it through the mitral valve into the left ventricle. from the left ventricle, the blood passes through the aortic valve to the aorta.

deoxygenated blood leaves through the right ventricle through the pulmonary artery. from the right atrium, the blood is pumped through the tricuspid valve (or right atrioventricular valve), into the right ventricle.

voluntary muscles are controlled by the cerebellum.