The layer of blood vessels consisting of an endothelial layer with a basement membrane is the tunica:

Correct Answer: C

Rationale: The tunica interna (C), or intima, is the innermost layer with endothelium and basement membrane. Arterioles (A) are vessels, externa (B) is outer, and media (D) is muscular.

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: C

Rationale: The foramen ovale (C) is the fetal atrial opening, shunting blood from right to left atrium to bypass lungs. Ductus venosus (A) shunts liver, ductus arteriosus (B) lungs, circle of Willis (D) is cerebral.

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.