2. Why are capillaries and not arteries or veins found in alveoli, nephrons, and villi?
Vessels must be small so that very little blood enters these tissues.
Vessels must be narrow so that only very small molecules can reach these tissues.
Vessel walls must be thin to allow ease of transfer of molecules to these tissues.
Vessels must be lightweight so that they do not interfere with the movements of these tissues.

Respuesta :

"Vessel walls must be thin to allow ease of transfer of molecules to these tissues" is why capillaries and not arteries or veins are found in alveoli, nephrons, and villi. The correct option among all the options that are given in the question is the third option or the penultimate option. I hope the answer helped you.