Which of the following statements is true?
a. arteries carry only oxygenated blood.
b. the systemic circuit leaves the heart from the left ventricle.
c. blood never passes through more than one capillary bed on its trip through the systemic circuit.
d. platelets survive a longer time than erythrocytes.
e. blood from the pulmonary system returns to the heart at the right atrium.

The true statement is option B.

Explanation:

The systemic circuit is the component of the circulatory system, which carries the blood from the heart, and supply it to the majority of the organs and tissues, and returns it back to the heart. The oxygenated blood from the lungs goes into the left atrium and is mediated towards the left ventricle in order to supply the blood to the organs of the body.  

The systemic circuit is different from the pulmonary circuit that only mediates blood between the heart and lungs.  

videntify the dna change shown in the diagram and explain how that change can result in the increased genetic diversity often seen among siblings.identify the dna change shown in the diagram and explain how that change can result in the increased genetic diversity often seen among siblings.

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.