Cardiovascular System

1. Cardiovascular System Aka: The Circulatory System

2. Structure • Heart • Blood Vessels • Blood

3. What does it do? • Moves the blood • Protects the body • Transports nutrients • Removes metabolic waste • Regulates body temperature

6. Your Diagram • 1. Aorta • 2. Vena Cava • 3. Right Pulmonary Artery • 4. Pulmonary Veins • 5. Right atrium • 6. Tricuspid Valve • 7. Right Ventricle • 8. Lower / Inferior Vena Cava

7. Your Diagram 9. Left Pulmonary Artery 10. Left Pulmonary Veins 11. Left Atrium 12. Mitral or Bicuspid Valve 13. Aortic Valve 14. Left Ventricle 15. Septum

8. Four Steps of Circulation • Step 1: From right side of heart to lungs to collect O2 turning blood bright red and CO2 leaves the capillaries through diffusion. • Step 2: Oxygenated blood returns to the left side of the heart. (Pulmonary Circulation) • Step 3: Blood is pumped to all parts of the body distributing O2 and nutrients • Step 4: Blood returns to the right side of the heart a reddish-blue color to be oxygenated again (Systemic Circulation)

9. What allows the heart to keep its beat? • The sinoatrial node abbreviated SA node is the impulse-generating (pacemaker) tissue located in the right atrium of the heart, and thus the generator of normal sinus rhythm. • It is a group of cells positioned on the wall of the right atrium, near the entrance of the superior vena cava.

11. What allows the heart to keep its beat? • http://www.pennmedicine.org/encyclopedia/em_DisplayAnimation.aspx?gcid=000001&ptid=57 • http://kidshealth.org/parent/medical/body_basics/heart.html

12. What allows the heart to keep its beat? • The cardiac conduction system is a group of specialized cardiac muscle cells in the walls of the heart that send signals to the heart muscle causing it to contract. The main components of the cardiac conduction system are the SA node, AV node, bundle of His, bundle branches, and Purkinje fibers. The SA node (anatomical pacemaker) starts the sequence by causing the atrial muscles to contract. From there, the signal travels to the AV node, through the bundle of His, down the bundle branches, and through the Purkinje fibers, causing the ventricles to contract. This signal creates an electrical current that can be seen on a graph called an electrocardiogram (EKG or ECG). Doctors use an EKG to monitor the cardiac conduction system’s electrical activity in the heart.

13. 2 Phases of a Heart Beat • In the diastole phase, the heart ventricles are relaxed and the heart fills with blood. • In the systole phase, the ventricles contract and pump blood to the arteries. • One cardiac cycle is completed when the heart fills with blood and the blood is pumped out of the heart.

14. Blood Pressure • The force of blood pushing against artery walls • Strongest when heart contracts (systolic or the higher number) • Weakest when heart relaxes (diastolic or the low number) • 120/80 is considered normal BP

15. Pulse • Rhythmic contractions of arteries can be felt through the skin. • Keeps pace with heart beat. • A way to measure vital health statistics

16. Types of Vessels

17. Structure of the Blood

19. Blood is made of… • Erythrocytes (RBC) • Leukocytes (WBC) • Platelets • Plasma

20. Differentiated Blood Cells

21. Erythrocytes • Red Blood Cells (RBC) • Transport Oxygen and Carbon Dioxide • Flattened Doughnuts with depressed center for increased surface • Flexible to get through vessels • No nucleus – last 120 days broken down in spleen

22. Leukocytes • White Blood Cells (WBC) • Protects body from foreign microbes and toxins • Found in blood stream and some tissue • Last 18-36 days • Three types

23. Types of Leukocytes • Lymphocytes: Immune function • Granulocytes: Destroy bacteria, viruses, parasites • Macrophages: Break down old blood cells and foreign matter like dust and asbestos

24. Platelets • Aka: Thrombocytes • Clot blood • Release coagulating chemicals • No nucleus • Fragments of Megakaryocytes • Stimulate Immune System and Fight Infections

25. Plasma • Clear liquid protein and salt part of the blood • 55% of our blood volume • 95% of plasma is H2O • Contains: nutrients, clotting factor, hormones, antibodies, vitamins, lipids, sugars, other proteins, metabolic waste

26. Blood Formation - Hematopoiesis • Bone Marrow produces red blood cells, most white blood cells and platelets • All blood cells originate from stem cells • Production is based on body need such as infection or bleeding

27. How blood circulates…. • Closed system of blood vessels • Four chambers of the heart • http://www.youtube.com/watch?v=xagOnC6sZEU

28. The Heart - Structure • Four cavities that fill with blood • Two are Atria (Upper “Round” Half) • Two are Ventricles (Lower “pointed” Half) • Points to left side of chest at the bottom • Size of fist • Pumps 4300 gallons / day

29. Heart - Function • Connects to Aorta at the top. Main artery carrying blood away • Pulmonary Artery connects heart to lungs • Two largest veins = Carry blood into heart are superior vena cava and inferior vena cava.

30. Heart - Function • Cardiac Muscle • Contracts 70-80 times per minute • Nerves connected to the heart regulate speed of muscle contraction

31. Blood Vessels - Structure • Three Types: • Arteries - thick and flexible due to forceful bloodflow • Veins- appear blue, thinner walls than arteries, less forceful flow • Capillaries – tiniest vessels, connect arteries and veins. Very thin walls

32. Blood Vessel - Function • Arteries: Carry oxygenated blood from heart to tissues. Arteries to Arterioles to capillaries • Veins: Carry deoxygenated blood to heart. Capillaries – Venuoles – Veins • Capillaries: gas exchange and absorb metabolic waste