1. The heart and the circulatory system

2. Purposes of the circulatory system Carry nutrients and Oxygen to cells Carry waste and Carbon dioxide away from cells Distribute heat throughout the body to help maintain body temperature Maintain body fluid levels Defend against invading pathogens

3. The Heart The central pump that moves blood around the body Split into 4 chambers (Left and right atriums, left and right ventricles) Atriums are sacs that collect blood coming into the heart Ventricles are chambers with thick muscle walls that pump blood out of the heart

4. Right Atrium: collects blood coming back from the body Right Ventricle: pumps blood to the lungs (to get oxygen) Left Atrium: collects blood coming back from the lungs Left Ventricle: pumps blood to the rest of the body

5. Other heart structures Vena Cava: Large vein that collects blood coming back from the body (There are two – superior, which collects blood coming from the upper body, inferior that collects blood coming from lower body) Aorta: large artery that carries blood away from the left ventricle to the body Pulmonary arteries: carry blood away from the right ventricle to the lungs Pulmonary veins: carry oxygenated blood to the left atrium from the lungs