Circulatory System

Blood Vessels

• arteries, veins, capillaries
• arteries= blood
• veins = blood ---> heart
• capillaries= arteries --> veins

Arteries

• "bright red"blood vessel
• thick in walls bc high pressure
• carry oxygenated blood

Veins

• "dark red" or blue veins in all diagrams
• less muscular than arteries
• closer to the skin
• carry de-oxygenated blood
• have valves to help blood flow against gravity (see diagram)

Capillaries

• Capillary walls contain small pores that allow certain substances to pass in and out
• oxygen goes out, CO2 goes in
• carry both oxygenated and de-oxygenated blood

The Heart

• has four chambers
• right and left atrium- holds de-oxygenated blood
• right and left ventricals- holds oxygenated blooc

4 Important Blood Vessels

• Vena cava= body blood into RA
• Pulmonary artery=blood to lungs
• Pulmonary veins=from lungs to LA
• Aorta= Blood from LV to body

Valves

• Blood goes in but cannot go back out
• "Lub Dub" sound its the valves opening and closing

4 Important valves

• Tricuspid valve
• Pulmonic valve
• Mitral valve
• Arotic valve