2Examine the exterior or outside surface of the heart. Heart ExteriorExamine the exterior or outside surface of the heart.Locate the blood vessels on the surface of the heartand the places where blood vessels enter and leavethe heart. Look at the picture below to help you.large blood vesselsentering and leavingthe heartsurface blood vessels
3blood vessels entering The blood vessels on the surface of the heart carryblood to the cells of the heart. The larger bloodvessels entering and leaving the heart carry bloodto and from the heart. There are six blood vesselsentering and leaving the heart.surface bloodvesselsblood vessels enteringand leaving the heart
4Turn the heart over and examine the interior of the Heart InteriorTurn the heart over and examine the interior of theheart. Notice there are four chambers or compartmentsin the heart. The bottom chambers are much larger thanthe top chambers.top chambersbottom chambers
5The chambers on the top are called atriums and the chambers on the bottom are called ventricles. Twoblood vessels enter each atrium and one blood vesselleaves each ventricle. The atrium and ventricle oneach side are connected by a valve. The valve onlyallows the blood to flow in the correct direction, fromthe atrium to the ventricle.atriumvalveventricle
6Blood low in oxygen comes from the body and enters Blood CirculationBlood low in oxygen comes from the body and entersthe right atrium. The right atrium contracts and pushesthe blood into the right ventricle. The right ventriclecontracts and sends the blood to the lungs to pick upoxygen and get rid of carbon dioxide.right atriumright ventricle
7After the blood leaves the lungs, it travels back to the left atrium. The left atrium contracts and sends theblood to the left ventricle. The left ventricle contractsand sends the blood out of the heart to deliver oxygento all the cells of the body.left atriumleft ventricle
8Questions & Conclusions 1. What is the function of the blood vessels on the surfaceof the heart?2. How many blood vessels enter and leave the heart?3. How many chambers or compartments are there inthe heart?4. Which chambers are larger, the top or bottom?5. How many blood vessels enter each atrium?6. How many blood vessels leave each ventricle?7. Are the atrium and ventricle on each side connected?8. Where are the valves located?9. What is the function of the valves?10. Where does blood low in oxygen enter the heart?11. Where does the blood go after it leaves the rightatrium?
912. Where does the blood go after it leaves the right ventricle?13. What does the blood pick up when it is in the lungs?14. What does the blood get rid of when it is in the lungs?15. Where does the blood go after it leaves the lungs?16. Where does the blood go after it leaves the leftatrium?17. Where does the blood go after it leaves the left18. What does the blood deliver to all the cells of thebody?*Label the diagram showing the structure of the heartand the circulation of blood through the heart. Usethe diagram on the board to help you.