Getting to the Heart of the Matter…

1. Getting to the Heart of the Matter… The Circulatory System

2. The Circulatory System • Components: • Heart – cardiac muscle, involuntary • blood vessels – lined w/smooth muscles • Blood – is a tissue • AKA (also known as) - Cardiovascular System • Cardio – means heart • Vascular – means blood vessels

3. The blood vessels of the circulatory system reachthroughout the entire body • Blood flows through these vessels to every organ in the body • Capillaries reach every cell of the body

4. Functions of the Circulatory System • Carries needed materials to the cells • Oxygen from the lungs • Glucose for energy • Carries waste products away from the cells • Carbon dioxide (CO2) • Other wastes • Carries cells that fight disease throughout the body (white blood cells)

5. The Heart • The heart is made up of four chambers (sections) • Split into left and right side by a muscular wall (septum) • The heart works with the lungs to provide oxygen to the body

6. The Parts of the Heart • Atrium – the two upper chambers of the heart • Receive blood coming into the heart • Ventricles – the two lower chambers of the heart • Pump blood out of the heart • Valve – a flap of tissue that prevents blood from flowing backward • Located between each chamber and in the veins

7. Label the heart on your notes

8. How the Heart Works • The heart muscle relaxes and the atrium fill with blood • The atrium contract, pushing blood into the ventricles • The ventricles contract to pump the blood out of the heart and into the arteries

9. The Heart Beat • The sound that your heart makes is the valves between the chambers opening and closing • lub-dub, lub-dub

10. Your heart does not work alone • Your brain tracks the conditions around you—climate, stress, and your level of physical activity—and adjusts your cardiovascular system to meet those needs

11. Regulation of Heartbeat • The pacemaker regulates the heart beat. • A group of cells located in the right atrium • Sends signals that make the heart contract • Constantly receives internal stimuli about the body’s oxygen needs

12. Two Loops • In one loop • blood travels from the heart to the lungs and back to the heart. • In the second loop • blood travels from the heart to the body and back to the heart. http://www.mikecurtis.org.uk/heart.htm

13. First Loop – to the lungs and back • Blood from the body enters the right atrium • Through a valve to the right ventricle • Out of the right ventricle into the pulmonary artery  to the lungs where the blood releases waste gases and picks up oxygen • L & R atria pump together

14. Do right and left seem backward? • That's because you're looking at an illustration of somebody else's heart • To think about how your own heart works, imagine wearing the picture on your chest

15. Second Loop-to the body and back • The newly oxygen-rich blood (shown in red) returns to the heart and enters the left atrium • Through a valve into the left ventricle • The left ventricle contracts, pushing the blood into the aorta  eventually to all parts of the body • L &R ventricles pump together

16. http://www.pbs.org/wgbh/nova/heart/heartmap.html

17. Three kinds of Blood Vessels • Arteries – blood vessels that carry blood away from the heart • Veins – blood vessels that carry blood back to the heart • Capillaries – tiny blood vessels capable of exchanging substances between the blood and body cells

18. Three kinds of Blood Vessels

19. Study Your Notes!! • You will take a quiz over these notes tomorrow