Arterioles are small arteries that branch off from larger arteries and carry blood to the capillaries. They are much smaller than arteries, with a diameter of only about 10-100 micrometers. Arterioles have a muscular wall that can constrict or dilate to control the flow of blood to the capillaries.
Capillaries
Capillaries are the smallest blood vessels in the body, with a diameter of only about 5-10 micrometers. They are formed by a single layer of endothelial cells and allow for the exchange of oxygen, carbon dioxide, and other nutrients between the blood and the tissues.
Arterioles and capillaries are essential for the functioning of the circulatory system. Arterioles control the flow of blood to the capillaries, while capillaries allow for the exchange of oxygen, carbon dioxide, and other nutrients between the blood and the tissues.