NEET PG DENTAL EXAM

Detailed explanation-1: -The muscular middle layer is called the tunica media, and the outermost layer is called the tunica adventitia. Because capillaries are only one cell layer thick, they only have a tunica intima. This ultra-thin design allows for the exchange of gases and nutrients through the capillary walls.

Detailed explanation-2: -Capillaries are thin-walled vessels composed of a single endothelial layer. Because of the thin walls of the capillary, the exchange of nutrients and metabolites occurs primarily via diffusion. The arteriolar lumen regulates the flow of blood through the capillaries.

Detailed explanation-3: -The vessel walls of veins are thinner than arteries and do not have as much tunica media. The tunica media is smaller in relation to the lumen than in arteries.