3.6.1 Blood Vessels
- The circulatory system includes structures that move the transport fluids throughout the body (incl. blood vessels and the heart): - arteries: thick walled blood vessels containing cardiac muscle that helps maintain blood flow via contractions called the pulse. Conduct blood away from the heart, towards body tissues. - veins: relatively thin-walledblood vessels which containone-way valves that aid forwardblood movement. Conduct bloodtoward the heart, away from thebody tissues. - capillaries: microscopic bloodvessels with very thin walls. Readily exchange dissolved materials between body tissues and blood, by diffusion.
