What are the 5 differences between arteries and veins based on the observations under the microscopes?
For a typical artery and vein, here are some differences based on a sectional view through a microscope. 1. Arteries are round, with a relatively thick wall. Veins are usually flattened or collapsed, with a relatively thin wall. 2. The tunica interna in arteries is usually rippled due to vessel constriction. In veins, it is often smooth. The internal elastic membrane is present in arteries, but absent in veins. 3. The tunica media in arteries is thick, and dominated by smooth mucle and elastic fibers. In veins, it is thin, dominated by smooth muscle and collagen fibers. The external elastic membrane is present in arteries, absent in veins. 4. The tunica externa in arteries is composed of collagen and elastic fibers. In veins, it is collagen, elastic, and smooth muscle fibers. 5. Arteries have a small lumen, veins have a large lumen.
