Capillaries in the human body are responsible for the flow of blood. Due to this flow of blood in the capillaries, oxygen is given to each cell of the body. There are capillaries on the lungs and when lungs get oxygen during breathing, then the oxygen from the lungs are diffused into capillaries which form a network on the lungs. The blood flows towards the cells and the oxygen is diffused into the cells from the capillaries. This diffusion process in the capillaries because of the concentration gradient is known as capillaries diffusion.
