Pulse is defined as a(n):

Correct Answer: A

Rationale: Pulse is the arterial wall’s expansion and recoil (A) with each heartbeat. B is the cause, C is systolic pressure, D is diastolic, not the pulse itself.

Correct Answer: B

Rationale: The first branches of the aorta are the coronary arteries (B), arising from the aortic root to supply the heart. Brachiocephalic (A), carotid (C), and subclavian (D) branch from the aortic arch.

Correct Answer: C

Rationale: Blood from the right ventricle exits via the pulmonary valve (C) to the pulmonary artery. Tricuspid (A) is inflow, bicuspid (B) is left-sided, and aortic arch (D) is systemic.

Correct Answer: D

Rationale: the absolute refractory period (~0.25-0.3 s) lasts through systole (A), is longer than skeletal muscle (B, ~0.002 s), prevents restimulation (C), and matches the action potential (D).

Correct Answer: B

Rationale: Arterioles (B) regulate flow via resistance (smooth muscle). Arteries (A) conduct, capillaries (C) exchange, venules (D) collect.