2. Human Circulatory System: Also known as the cardio-vascular system It is a closed system, which means that blood is confined within vessels

3. The Human Circulatory System contains 3 parts: 1. Heart 2. Blood Vessels 3. Blood

4. The Heart A. Your heart is a muscle, mostly cardiac muscle –It continually beats without stopping for your entire life –It pumps about 1/3 cup of blood with each beat, and about 2,000 gallons of blood daily

5. The Heart: b.. Birds and mammals have a 4-chambered heart (2 atria and 2 ventricles) *Fish have 2 chambers and reptiles have 3 chambers

6. Function of the heart: Every cell in your body needs oxygen in order to live and function. The purpose of the heart is to deliver the oxygen-rich blood to every cell in the body

7. The 4 main parts of the heart are: 1.The Atria 2.The Ventricles 3.The Septum 4.Valves

9. 1. The Atria: Top two chambers of the heart Have thin walls They collect blood returning to the heart from the body They then pump blood to ventricles through valves

10. 2. The Ventricles Bottom two chambers Have much thicker walls More powerful than the atria, The left ventricle is the strongest chamber because is pumps blood to the rest of the body. The right ventricle pumps blood to the lungs to pick up oxygen

12. The Septum Thick tissue that separates the two sides of the heart so that blood does not mix

13. Heart Valves There are 4 valves in the heart that help to direct blood flow Blood should only move in one direction to avoid contamination between oxygen-poor blood and oxygen-rich blood –As they open and close, the valves produce sounds that can be heard with a stethoscope –These sounds can often tell your doctor about your heart’s function

14. Semilunar Valve

16. There are 3 main types of blood vessels: Arteries Veins Capillaries

18. Arteries Carry oxygen- rich blood AWAY from the heart toward the body.

19. Veins Carry oxygen-poor blood from capillaries back to the heart and lungs

20. Capillaries Thin-walled blood vessels in which gases, nutrients, wastes, and hormones are exchanged Are only one cell layer thick and microscopic in size

21. Capillary Bed

22. There are 3 different types of Circulation throughout your body: 1.Coronary (to the heart) 2.Pulmonary (to the lungs) 3.Systemic (to the body)

23. Coronary Circulation Refers to the movement of blood through the tissues of the heart

24. Pulmonary Circulation The movement of blood from the heart to the lungs and back to the heart again Blood flows to the lungs to pick up oxygen

25. Systemic Circulation The movement of nutrient-rich blood to all of the tissue located throughout your body

30. What is Blood Pressure? Pressure exerted by the blood against artery walls Consists of 2 numbers: –Systolic –Diastolic

31. Blood Pressure: NOT IN NOTES! Systolic Pressure: –The pressure as a result of contraction of the left ventricle Diastolic Pressure: –Pressure as a result of the relaxation of the left ventricle

32. What should my blood pressure be? Typical blood pressure for an adult is: 120 70 Systolic Diastolic

33. High Blood Pressure: Also known as hypertension Result of stretched out arteries which makes the heart work harder to force blood through Can also result from a narrowing of arteries

34. What is my Pulse? A measure of how fast the heart is contracting Pulse is taken in an artery Normal resting pulse rate for an adult is 60-80 bpm (beats per minute)

35. Pulse Sites

36. Does our heart rate change as we age? AgePulse Newborn130 3 months140 6 months130 1 year120 2 years115 3 years100 4 years100 6 years100 8 years90 12 years85 Adult60-100

38. Two problems of the circulatory system we will be discussing are: 1.Stroke 2.Heart Attack

39. Stroke Results from a blockage of artery (Carotid artery) towards the head As a result, nervous tissue in the brain dies

40. HEART ATTACK!

41. Heart Attack When part of the heart muscle is damaged or dies due to lack of oxygen. Oxygen is carried to the heart by the arteries Most heart attacks are caused by a blockage in these arteries.

42. What causes a Heart Attack? HIGH FAT DIET!!!!

44. How does circulation maintain homeostasis? The heart keeps the blood flowing through the body which regulates body temperature and also delivers nutrients that the body needs, thereby maintaining homeostasis

46. How does your heart keep beating? The answer lies in a special group of cells that have the ability to generate electrical activity on their own. These cells separate charged particles. This produces electrical impulses in the pacemaker cells which spread over the heart, causing it to contract. These cells do this more than once per second to produce a normal heart beat of 72 beats per minute. The natural pacemaker of the heart is called the Sinoatrial node (SA node). It is located in the Right Atrium. The heart also contains specialized fibers that conduct the electrical impulse from the pacemaker (SA node) to the rest of the heart

47. Steps of Pulmonary Circulation: 1.Veins bring oxygen-poor blood back to the heart through the Vena Cava. 2.Right atrium fills with the de-oxygenated blood and then contracts, pushing the blood through a one-way valve into the right ventricle 3.The right ventricle fills and then contracts, pushing the blood into the pulmonary artery which leads to the lungs. (the blood entering the lungs will be dark red in color because it has little oxygen) 4.In the lung capillaries, CO 2 is dropped off and O 2 is picked up 5.The fresh, oxygen-rich blood (bright red) enters the pulmonary veins and returns to the heart, re-entering through the left atrium 6.Now, oxygen-rich blood is ready to go to the body!