Circulatory System

1. Circulatory System

2. Circulatory System • Consists of the blood, heart, and blood vessels

3. Blood • Type of Connective tissue • 4-6 liters in the body • Has a liquid and solid portion.

4. Liquid portion: Plasma (55%) • (mostly water) • Solid portion: platelets, Red blood cells, and White blood cells (45%) • Buffy coat (wbc and platelets) less than 1% • The bottom is red blood cells

6. The “formed elements” of blood • Erythrocytes (red blood cells) • Leukocytes (white blood cells) • Thrombocytes (platelets)

7. Functions of Blood • Transportation- waste nutrients, and hormones • Regulation- body temp, pH • Protection- blood clots to prevent blood loss and fights infections

8. Plasma • Extra cellular matrix in blood • Mostly water (>90%) • Proteins (7%) produced by the liver • Albumin- helps with water balance in blood stream • Globulin- transports HDL and LDL proteins • Fibrinogen – clotting proteins • Other solutes such as oxygen, carbon dioxide, urea

9. Structure of a Erythrocyte • Small (7micrometers by 2 micrometers) • Biconcave • Flexible • No nucleus or organelles • “ghost of a cell” • Packed with hemoglobin • *2 ½ trillion in one person*

10. Hemoglobin carries oxygen • Oxygen binds to the iron containing heme group • Some carbon dioxide will bind as well

11. Oxygen loading and unloading • Oxygen is loaded onto the heme in the lungs forming oxyhemoglobin (bright red) • Oxygen is unloaded in the tissues forming deoxyhemoglobin (darkish red to purple)

12. Lifespan of Erythrocytes • Made in the red marrow of the long bone • Live for about 120 days • Dead RBCs go to the spleen were they are decomposed

13. Anemia • Reduction in oxygen carrying capacity • Measured as hematocrit- percentage of blood volume made up by RBCs (should be 45%) • Symptoms: Tired, bruising easily • Types of anemia • Iron deficiency • Hemorrhagic (bleeding) • Hemolytic (breaking RBC) • Sickle Cell (genetic disorder) • CO poisoning (takes place of O)

14. Sickle Cell Anemia • Many RBCs have a Sickle like shape • Genetic Recessive disorder • You can be a carrier or actually have sickle cell anemia • Thought to be a defense against malaria

15. Polycythemia • Excess of RBCs in blood • Increases blood viscosity (difficult to circulate blood)

16. White Blood Cells (WBC) • “Leukocytes” • Fewer in number (5,000-10,000 in the body) • True cells with nuclei and organelles • Guard/Fight Infections • Larger than RBCs • Found in the “Buffy Coat”

17. 2 different classes of WBCs • Granular Leukocytes (Granulocytes) • Agranular Leukocytes (Agranulocytes)

18. Granular leukocytes • Neutrophils- fight bacterial infection • Eosinophils- fight parasitic infection • Basophils- release histamines, allergic responses

19. Agranular Leukocytes • Lymphocytes- • T lymphocytes attack virus infected cells and tumors • B lymphocytes produce antibodies • Monocytes- largest WBC, phagocytize, high with chronic infections

20. Leukemia • Uncontrolled reproduction of WBCs • Named for abnormal cell type • Myelocytic leukemia – uncontrolled granular line • Lymphocytic leukemia- uncontrolled agranular line

21. Mononucleosis • Caused by ebstein-barr virus • Excessive numbers of agranulocytes and basophils

22. Platelets • “Thrombocytes” • Important in Clotting

23. Hemostasis: Stopping Blood loss • Tear a blood vessel due to a cut or scrape • Positive feedback cycle • Platelets form a temporary plug • Coagulation- formation of clot with fibrin strands

24. Hemophilia • Blood is not able to clot properly because its missing a clotting factor • Bleed for a long time • located on the X chromosome • females can carry and pass to sons

25. Hemophilia

26. Blood Typing • Erythrocytes carry antigens on their surface • Antigens make the immune system respond • Antigens are proteins • Plasma contains antibodies that will attack FOREIGN antigens

27. The ABO Blood System • 4 Types: A, B, AB, and O • Each type has specific antigens on the RBC surface • specific antibodies in the plasma

28. The ABO Blood System • Type A blood, has A antigens on the red blood cell’s surface. • Type B blood will have B antigens. • Type AB blood will have A and B antigens • Type O blood IS THE EXCEPTION, it has NO antigens on its surface

29. Antibodies • Located in the plasma • protect body against foreign substances INCLUDING foreign blood types

31. The ABO Blood System • Blood type AB is the most rare. • Blood type O is the most frequent blood type.

32. The ABO Blood System • Type O- is considered to be a “universal donor” • Type AB+ is considered to be a “universal recipient”

33. Rh Factor • Another way to classify blood • “Rhesus Factor” • Rh+ is positive for the Rh protein on RBC surface • Rh- negative for the Rh protein on RBC surface

34. Rh Factor • people with Rh+ blood will not have Rhantibodies • People will Rh- blood will have Rhantibodies in plasma • react by coagulating when exposed to Rh+ blood.

35. Hemolytic disease of the newborn • Seen with children who are Rh+ and their mother is Rh- • Blood is transferred through the placenta, mother develops strong antibodies against + • 1st child will be fine, next child is at risk from mom’s antibodies attacking baby • Rhogam is given to the mother to protect baby

36. Transfusions • Transfusions- blood from one person is taken OUT of their body and PUT into another person’s Body.

37. Transfusion Reaction • Occurs when antibodies attack foreign RBCs that have entered the body • Coagulation • Heart attack, stroke, renal failure may result

38. The Heart • Provides the force to propel blood through the system • Located in thoracic cavity, medial to the lungs, anterior to the vertebrae, and posterior to the sternum

39. Two Circuits • Heart is involved in the two circuits of the circulatory system. • Pulmonary • Heart, lungs, Heart • Systemic • Heart, body, heart

40. Stats of the heart • Size: clenched fist • Shape: Cone shaped • Pointed apex, points toward left and rests on diaphragm

41. Surroundings • Surrounded by the pericardial cavity • Parietal pericardium: Lines the PERICARIDAL SAC • Visceral pericardium “epicardium” covers the OUTER SURFACE of the heart

42. Layers of the Heart From OUT to IN • Epicardium: covers outer surface • Myocardium: muscle (walls) • Endocardium: lining of the inside of the heart

43. Chambers of the Heart • 2 Atria and 2 Ventricles • Atria- superior; RECEIVE blood, thin walls • Ventricles- inferior; PUMP blood, thick walls

44. Atria • Small and ear like in shape. Located superiorly. • There is a right and a left • The right receives deoxygenated blood from the body • The left receive oxygenated blood from the lungs.

45. Atria on a heart

46. The Heart- Ventricles • take up the majority of the heart. • Left is largest and most muscular • right receives deoxygenated blood from the right atrium and pumps out to lungs • left receives oxygenated blood from the left atria and pumps out to body

47. Ventricles

48. Valves • All 4 Valves prevent back flow of blood • 2 Atrioventricular (AV) valves prevent blood from coming back out of the ventricles and into the atria • 2 Semilunar values prevent backflow from the great vessels into the ventricles

49. AV valves • Bicuspid- between Left atria and left ventricle • Tricuspid- between right atria and right ventricle • Attached to chordaetendinae “Heart stings” which are attached to papillary muscles

50. Semilunar Valves • Aortic valve and pulmonary valve • Aortic semilunar valve separates the left ventricle and aorta • Pulmonary semilunar valve separates the right ventricle and the pulmonary artery