2. Here Is Your Heart Let’s Find Out! How Does It Work?

3. Amazing Facts! The heart beats an average of 3 billion times during your life. About 8 million blood cells die every second. It takes 20 sec. for a red blood cell to circulate the whole body. The heart pumps about 1 million barrels of blood during the average lifetime.

4. The Heart The Heart Is A Muscle Divided Into Left And Right Halves It Pumps The Blood 5 Liters Per Minute When You Are At Rest

5. Where Does The Blood Go? To The Head To The Limbs To The Internal Organs To The Skin To The Heart Itself Everywhere!

6. Through Arteries Carry Blood Away From The Heart Muscular Walls Maintain Blood Pressure Oxygen Rich Blood

7. To The Capillaries One Cell –Layer Thickness Site Of Gas Exchange Cells Pass Single File Help Control Body Temperature

8. To The Veins Carry Blood Back To The Heart Less Muscular Low Pressure Oxygen-Poor Blood Contain Valves

9. And Back To The Heart

10. During Your Lifetime Your Heart Will Beat Some 2.5 Billion Times Pump Enough Blood To Fill About 2000 Swimming Pools And Never Stops To Rest How Does It Do It?

11. The Heart Has 4 Chambers Right Atrium Left Ventricle Left Atrium Right Ventricle

12. Let’s Follow The Flow 1.Body To Right Atrium 2.To Rt. Ventricle 3.To The Lungs 4.From The Lungs To The Lt. Atrium 5.To Lt. Ventricle 6.Out To The Body

13. The Right Side… Oxygen-Poor Blood Enters The Heart At The Right Atrium Passes Through The Tricuspid Valve Enters The Right Ventricle Passes Out Through The Pulmonary Artery RA RV PA

14. To The Lungs Where… 1.Waste Carbon Dioxide Is Removed 2.Needed Oxygen Is Gained 3.Exits Through The Pulmonary Veins To…

15. …The Left Side Oxygen-Rich Blood Enters The Left Atrium Passes Through The Bicuspid (Mitral)Valve To The Left Ventricle Out The Aorta To The Body LA LV

16. Let’s Watch It Happen Very Cool!

17. The Heart Is Controlled By Electrical Signals

18. Pacemakers Coordinate Contraction SA Node Initiates AV Node Continues Conduction Pathways Finish

19. Artificial Pacemakers Control Pace When The Heart Can’t

20. Coronary Circulation Begins In Aorta Supplies The Heart Muscle With Blood Shown Here In An Arteriogram Narrowing Can Cause Pain (Angina) Blockage Results In A Heart Attack (M.I.)

21. Narrowing Can Occur In Other Arteries Too

22. We Can Check The Heart With An Echocardiogram Sound Is Used Shows The Chambers Shows The Valves Shows Blood Flow In Color It’s Painless

23. To Be Heart Healthy Exercise Regularly Eat Heart-Healthy Meals Reduce Stress Don’t Smoke Get Plenty Of Rest

24. OTHER ANIMALS MAY CIRCULATE BLOOD DIFFERENTLY THAN IN MAMMALS PART - 2

25. Do Worms Have Hearts? Worms have a closed circulatory system. Their blood travels through vessels. Worms have 5 “heart arches” that move blood through vessels. The top vessel carries blood forward. The bottom vessel moves blood rearward. Worms don’t have red blood cells.

26. WORM CIRCULATION

27. INSECT CIRCULATION Insects have an open circulatory system. Blood doesn’t flow through vessels Blood doesn’t carry oxygen and isn’t red. Insects don’t need much oxygen.

28. Other Heart Arrangements