What are two things that parasites can do?

Parasites are organisms that infect the body of another living being and live off their hosts to survive. While some parasites create no symptoms in their hosts, others can cause severe illness. Parasitic infections occur when parasites grow, reproduce, or invade organ systems that make their hosts ill.

hello there the answer is d

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.