Which blood vessels are composed of a single endothelial layer?

Correct option is C

(c) Capillaries

Sol.Capillaries are smallest blood vessels composed of a single endothelial layer, allowing efficient exchange of oxygen, nutrients, and waste between blood and tissues.

Information Booster:

• Capillaries connect arteries and veins.
• Function:Gas exchange, nutrient diffusion.
• Types: Continuous, Fenestrated, and Sinusoidal capillaries.
• Capillary walls are one-cell thick, allowing rapid diffusion.
• Capillary beds help in tissue perfusion.
• Diseases: Capillary fragility can lead to edema and bleeding disorders.

Additional Information:

• (a) Arteries → Have thicker walls, carry oxygenated blood.
• (b) Veins → Have valves, carry deoxygenated blood.
• (d) Atrium → Chamber of the heart, not a blood vessel.