except for the pulmonary vein) Allows diffusion of gases and nutrients from blood into the body cells Wall Thick, muscular Thinner Very thin, one cell thick Lumen Small Large Very small ...
except for the pulmonary vein) Allows diffusion of gases and nutrients from blood into the body cells Wall Thick, muscular Thinner Very thin, one cell thick Lumen Small Large Very small ...
Exercise increases your blood pressure, which can expand the veins, and while lifting heavy weights, muscle contractions can ...