1. Cardiovascular/Circulatory System

3. Consists of…. Blood vessels Blood Heart

4. Blood Vessels Two pathways: –Pulmonary Circulation Carries blood to lungs and back –Systemic Circulation Carries blood to body and back

5. Capillaries of head and arms Capillaries of abdominal organs and legs Inferior vena cava Pulmonary vein Capillaries of right lung Superior vena cava Aorta Pulmonary artery Capillaries of left lung

6. Pathway of Circulation-3 Types of Vessels –Arteries- carries blood Away from heart Large Thick-walled, Muscular Elastic Oxygenated blood –Capillaries Smallest vessel Microscopic Walls one cell thick Nutrients and gases diffuse here –Veins Carries blood that contains waste and CO 2 Blood not under much pressure Carries deoxygenated blood

8. BLOOD! Body contains 4-6 L (Depending on size) Consists of –Water –Red Blood Cells –Plasma –White blood cells and platelets It is a tissue

9. What’s in Blood? Liquid Portion Carries Blood cells –Erythrocytes (RBC - red blood cells) –Leucocytes (WBC - white blood cells) Platelets (non cellular particles)

10. More About What's In Blood Proteins –Enzymes –Hormones – Endocrine System Nutrients - Digestive System Gases - Respiratory System

11. RBCs Transporters of –Oxygen –Carbon Dioxide RBC –Lack a nucleus –Contain hemoglobin –Disk-shaped

12. RBCs RBC are produced in red bone marrow of ribs, humerus, femur, sternum Lives for 120 days Old RBC are destroyed in liver and spleen

14. WBCs Fight infection Larger size Less in number Most live for a few days, but can live for months Several types All contain nuclei

15. Infection

16. Platelets PLATELETS are for CLOTTING blood Cell fragments Produced in bone marrow Short life span (1 week)

17. Blood Clotting Break in Capillary Wall Blood vessels injured. Clumping of Platelets Platelets clump at the site and release thromboplastin. Thromboplastin converts prothrombin into thrombin.. Clot Forms Thrombin converts fibrinogen into fibrin, which causes a clot. The clot prevents further loss of blood..

18. The Heart At REST, the heart pumps about 5 QUARTS of blood a minute. During EXTREME EXERTION (exercise) it can pump 40 quarts a minute. Composed of –Cardiac muscle –Mitochondria –Enclosed in a sac (Pericardium)

20. Heart Structure Four chambers –Two upper (Atria) Walls thinner Less muscular –Two lower (Ventricles) Walls thicker More muscular Do more work

21. Path Through The Heart Both Atria fill at same time –Right atrium receives oxygen POOR blood from body from vena cava –Left atrium receives oxygen RICH blood from lungs through four pulmonary veins After filled with blood atria contract, pushing blood into ventricle

22. More on the Path Right ventricle contracts and pushes oxygen-poor blood toward lungs against gravity, through pulmonary arteries Left Ventricle contracts and forces oxygen rich blood out of heart through aorta (largest vessel)

24. Heart Wall Epicardium – visceral layer of the serous pericardium Myocardium – cardiac muscle layer forming the bulk of the heart Fibrous skeleton of the heart – crisscrossing, interlacing layer of connective tissue Endocardium – endothelial layer of the inner myocardial surface

25. The Structures of the Heart Right Ventricle Right Atrium Left Atrium Inferior Vena Cava Tricuspid Valve Pulmonary Valve Pulmonary Veins Superior Vena Cava Aorta Pulmonary Arteries Aortic Valve Mitral Valve Left Ventricle Septum

26. Physiology of the Heart Pulmonary Valve: Keeps blood from flowing back into the right ventricle Bicuspid Valve: Prevents blood from flowing back into the left atrium, A.K.A. Mitral valve Left Atrium: Receives oxygen rich blood from the pulmonary veins Pulmonary Trunk: Transfers blood through the pulmonary arteries to the lungs

27. More Physiology Tricuspid Valve: Prevents backflow of blood to the right atrium Aorta: Blood flows from the aorta throughout the entire body Left Ventricle: Pumping chamber which forces blood through the aortic valve, more muscular than the right ventricle Right Atrium: Collecting chamber, Receives blood from the superior and inferior vena cava

28. More Physiology Inferior Vena Cava: Vein that brings oxygen-poor blood from the lower part of the body to the right atrium Aortic Valve: Prevents blood from going back into the left ventricle Interventricular Septum: Separates the pumping chambers of the heart Right Ventricle: Receives blood from the right atria

29. Heart Valves Heart valves insure unidirectional blood flow through the heart Atrioventricular (AV) valves lie between the atria and the ventricles AV valves prevent backflow into the atria when ventricles contract Chordae tendineae anchor AV valves to papillary muscles

30. Heart Valves Figure 19.9

31. Heart Valves Aortic semilunar valve lies between the left ventricle and the aorta Pulmonary semilunar valve lies between the right ventricle and pulmonary trunk Semilunar valves prevent backflow of blood into the ventricles

32. Heart Valves Figure 19.10

33. Blood Pressure Blood against the blood vessel’s walls (Systole – contraction of heart muscle, Diastole – relaxation of heart muscle) –The systolic pressure refers to the pressure recorded while the ventricles pump the blood. –The diastolic pressure refers to the pressure recorded as the ventricles fill with blood. A normal blood pressure is 120/80

34. Disorders Atherosclerosis Hypertension Heart Attack Stroke Endocarditis Pericarditis Deep Venous Thrombosis (DVT) Varicose Veins