Choose the correct description of a typical medium-sized vein.

Question

Quizplus · Accepted Answer

A medium-sized vein typically ranges from 2 mm to 9 mm in diameter and has a relatively thick tunica externa that contains longitudinal bundles of elastic and collagen fibers. The thin tunica media consists of one to two layers of smooth muscle cells. Option A describes a vein with a thick tunica externa composed mostly of collagen fibers, whereas option B describes a vein with a thin tunica media consisting of one to two layers of smooth muscle cells. Option C describes a vein with a diameter of approximately 0.4 cm and more smooth muscle cells and fewer elastic fibers. Option E describes a large vein with a diameter up to 2.5 cm, where the tunica media is dominated by elastic fibers rather than smooth muscle cells.

Choose the Correct Description of a Typical Medium-Sized Vein