The heart is located in the mediastinum behind the sternum and consists of four chambers - the right and left atria which receive blood, and the right and left ventricles which pump blood out of the heart. It pumps deoxygenated blood to the lungs and oxygenated blood to the rest of the body through a one-way valve system, and has inner layers of epicardium, myocardium and endocardium.

1. THE HEART

2. THERE IS ONE immediate need for THE HEARTTHE HEART IS ESSENTIAL FOR PUMPING BLOOD THROUGHOUT THE BODY--WITHOUT IT WE WOULD NOT GET THE OXYGEN OUR CELLS NEED TO SURVIVELOCATION OF THE HEARTLeft of the midline posterior to sternum in the mediastinum

3. The heart consists of four chambersRight atrium

4. Right ventricle

5. Left atrium

6. Left ventricle Looks like a lot to learn.

8. Right atriumThe right atrium receives blood from the Superior and Inferior Vena Cava, this is deoxygenated bloodThe blood flows from there into the right ventriclethrough the tricuspid valve. Valves are important--they keep blood from flowing back into the heart

9. Right VentricleBlood in the right ventricle is still deoxygenated

10. Blood from the right ventricle is pushed out of the heart into the pulmonary artery where it is transported to the lungs

11. There is a valve between the pulmonary artery and the right ventricle-pulmonary semilunar valve

12. In the lungs oxygen is received into the bloodFollow the arrows to see how blood flows through the heart.

13. Left Atrium After the blood has oxygen, it is returned to the heart through the pulmonary veins into the left atrium.

14. In left atrium blood is pushed into the left ventricle through the bicuspid valve.A closer look at the valves

15. Right VentricleThe left ventricle receives oxygenated blood from the left atrium

16. From here blood is pushed out to the body through the aorta. Cardiac muscle tissue

17. LAYERS OF THE HEARTEpicardium: outermost layer of the heartMyocardium: is the heart muscleEndocardium: innermost layer made up of simple squamous epithelium

19. What structures can you identify?

20. Blood flow through the heart