Blood Biology B3

Capillaries

Capillaries use diffusion to deliver food & oxygen directly to muscle tissues & take away carbon dioxide and any other waste materials. Walls usually just 1 cell thick so substances can easily pass in and out.

Blood is made of:

platelets, white blood cells, plasma & red blood cells

Red Blood cells

Job is to carry oxygen from lungs to every body cell. Doughnut shape gives them large surface area to…