Science 8: Cells & Systems

1. Science 8: Cells & Systems Circulatory System-The Heart

2. Circulatory System: • Delivers nutrients to every cell in our body • Transports oxygen to cells • Removes waste from cells

3. Our heart is an important part of our circulatory system! It has: 2 sides 2 pumps (one on each side)

4. Sides of the Heart The Right Side: Pumps bloodto the lungs to get fresh oxygen (and get rid of carbon dioxide) The Left Side: Receives oxygen-rich blood from the lungs Pumps oxygen-rich blood to your whole body

5. Top and Bottom Top 2 chambers: Atria Where blood enters the heart Bottom 2 chambers: Ventricles Where blood exits the heart

6. The Aorta: Largest artery in the body Sends blood to our whole body Remember *** Arteries carry blood away from your heart

7. Vena Cava: Large veins that carry blood to the heart Remember*** Veins carry blood to our heart

8. There are 2 Vena Cava: Superior Vena Cava Returns deoxygenated blood from the upper half of the body to the right atrium Inferior Vena Cava Returns deoxygenated blood from the lower and middle body to the right atrium

9. Valves: Blood flows from the right atrium to the right ventricle through the tricuspid valve. Blood flows from the left atrium to the left ventricle through the mitral valve.

10. The valves keep our blood flowing in one direction Lungs Left atrium Left Atrium Left ventricle Left ventricle Body Body Right atrium Right atrium Right ventricle Right ventricle Lungs Oxygenated blood Deoxygenated blood

11. Summary for Blood Vessels:

12. with Hemoglobin: • Contains iron (Fe) • Transport oxygen • flexible White blood cell Our Blood: Red Blood Cells + White Blood Cells + Platelets = 45 % of our blood Plasma, the liquid portion of our blood = the other 55% • Fight infection Platelets • Stop bleeding • Help form clots • Carries nutrients to cells • Carries waste away from cells