Which of the following is the role of the pulmonary artery?

a. The right ventricle chamber has a smaller overall capacity than the left ventricle: While true, this doesn't directly explain the difference in muscle thickness.

b. The right ventricle receives blood from right atrium, which has lower pressure than left atrium: Both ventricles receive blood from low-pressure atria. The pressure difference is between the circulation systems they pump blood into.

c. The right ventricle pumps a smaller blood volume than the left ventricle. The right ventricle pumps blood to the lungs, a low-pressure system. Therefore, the right ventricle wall (myocardium) is thinner than the left ventricle wall. The left ventricle pumps blood against the higher resistance of the systemic circulation, so its wall is much thicker and stronger.

d. The right ventricle pumps blood into pulmonary circulation, which has lower resistance than systemic circulation: This is the core reason for the difference in muscle thickness.

a: Decreased osmotic pressure - Decreased osmotic pressure would lead to fluid retention within the capillaries, not lymph production.

b. Increased hydrostatic pressure: Lymph is produced when there is an increase in hydrostatic pressure within the capillaries, which forces fluid and solutes out into the interstitial space, forming lymph.

c: Decreased hydrostatic pressure - Decreased hydrostatic pressure would result in decreased filtration of fluid from the capillaries, hindering lymph production.

d: Increased osmotic pressure - Increased osmotic pressure would draw fluid back into the capillaries, opposing lymph formation.