It is because the capillary wall is only one-cell-thick. In addition, they have a large total surface area in contact with body cell and the blood flow is low.
Capillary: A tiny blood vessel where substances are exchanged between the blood and the body cells.
The capillary is the smallest of the blood vessels. It is the site of gas exchange between the blood and the tissues.
Capillary vessels.
Capillaries are the tiny blood vessels where exchange of nutrients, gases, and waste products occurs between the blood and body tissues through the process of diffusion. They have thin walls that allow for efficient exchange of substances.
capillary
the blood vessel which allows gas exchange to occur is the capillaries
Capillary: these tiny blood vessels facilitate the exchange of nutrients, oxygen, and waste products between the blood and tissues. Their small size allows for efficient nutrient and gas exchange due to their proximity to body cells.
Nicotine is the blood vessels' constrictor. Not all blood vessels, of course, but mainly the peripheral blood vessels, including the brain capillary blood vessels.
The capillaries are the blood vessels that connect arteries and veins. Capillaries are the site of gas exchange in the body.
Capillary
Capillaries are the small blood vessels where oxygen is exchanged for carbon dioxide. They are located throughout the body and allow for the exchange of gases between the blood and tissues.
capillary blood sugar vs venous blood sdugar