Capillaries

Arterioles feed into networks of capillaries
1. The capillaries link the arterioles to the venules
2. BLOOD ENTERING THE CAPILLARIES IS OXYGENATED
  1. BLOOD LEAVING CARRIES LESS OXYGEN AND MORE CARBON DIOXIDE
Capillaries are very small vessels that spread throughout the tissues of the body
1. They branch between cells, no cell is far away from a capillary
  1. Substances can diffuse between cells and the blood quickly
  2. Because the diameter of the capillaries is small blood travels slowly allowing more time for diffusion
STRUCTURE
1. Thin walls with no elastic fibers or muscle
  1. Helps them fit between cells
2. Walls consist one one thin cell
  1. Diffusion occurs at a faster rate
    1. Oxygen and other molecules can quickly diffuse out
    2. Carbon dioxide and waste molecules can quickly diffuse in

Resource summary

	Created by giorgi.rebecca over 10 years ago