1. Unit J – Circulation and Blood

2. TYPES OF BLOOD VESSELS’

3. Arteries: Function: Transport blood away from the heart. Structure: Thick, elastic walls Location: Usually deep, along bones Veins: Function: Transports blood back to the heart. Structure: Thin walls; contain valves Location: Often on the surface surrounded by skeletal muscle

4. Capillaries: Function: Interconnect arteries to veins. Structure: Very thin walls ( 1 cell thick) Location: Everywhere; within a few cells of each other. Capillaries have sphincter muscles that can dialate and constrict the vessel. If all capillary beds were open at one time, it would decrease the blood pressure. If all the capillary beds were closed, it would increase blood pressure.

6. Arterioles and Venules: - All the features of arteries and veins apply to arterioles and venules, but on a smaller scale. -Arterioles leading into a particular organ or region, are often equipped with sphincter muscles. When triggered, they can dilate or constrict to regulate blood pressure, increasing or decreasing blood flow to that particular capillary bed. -The term afferent arteriole means the incoming arteriole where efferent arteriole is the outgoing arteriole.

8. MAJOR BLOOD VESSELS OF THE BODY 1. Aorta: This is the major blood vessel carrying oxygenated blood out of the heart. It leaves the left ventricle, loops over top of the heart creating the structure known as the aortic arch and descends along the inside of the backbone Function: Branches from this blood vessel feed the rest of the body.

9. 2. Coronary Arteries and Veins: The very first branches off the Aorta are the Coronary arteries. These relatively small blood vessels can be seen on the surface of the heart. Function: Feeds the heart muscle. (The heart does not receive its nutrients from the blood that travels through it. The muscle is too dense and thick and the blood is traveling through it to hard and fast.) -Coronary Vein takes the “spend blood” back to the heart.

10. 3. Carotid Arteries: These branches of the aortic arch take the blood to the head including the brain. Function: They are highly specialized in that they contain a number of different types of nerve endings: Chemoreceptors that detect oxygen content, and Pressure Receptors that detect blood pressure changes. Maintains homeostasis.

11. 4. Jugular Veins: The match for the Carotid Artery. They do not contain valves. Blood flow is through gravity. Function: They conduct blood out of the head region to the Anterior Vena Cava.

12. 5. Subclavian Arteries and Veins: Also branch from the Aorta. Travels under the Clavicle. Function: Branch to feed the arms (brachial artery). Veins collect blood from the arms.

13. 6. Mesenteric Arteries: These arteries branch off from the aorta as it travels posteriorly. They go to the intestines where they branch into capillaries that can be identified as villi. There is no corresponding mesenteric vein. Function: Feeding the organs of the digestive system and picks up newly digested nutrients in the body.

14. 7. Hepatic Portal Vein: Instead of a mesenteric vein, it is called a hepatic portal vein. Hepatic means liver; portal indicates that there is a capillary bed on both end of it. Function: Brings blood from Digestive tract to Liver.

15. 8. Hepatic Vein: Once the liver has done its thing to the blood, the blood must return to the venous system. Function: Carries blood from the liver to the posterior Vena Cava.

16. 9. Renal Arteries and Veins: The Renal Arteries branch off the dorsal aorta as it passes through the lumbar region of the body. Function: The Arteries take blood to the kidneys while the Renal Veins take blood away from the kidneys and back to the posterior Vena Cava.

17. 10. Iliac Arteries and Veins: When the dorsal aorta gets to the pelvic area. It branches into two Iliac Arteries, one goes down each leg. Off the iliac arteries is another branch that feeds the upper leg. This is called the Femoral artery. Function: To supply the legs with oxygenated blood and return deoxygenated blood to the Posterior Vena Cava.

18. 11. Anterior (Superior) and Posterior (Inferior) Vena Cava: Large Vein that collects all the deoxygenated blood from smaller veins to the heart (right atrium). The largest vein of the body. Function: Large Vein that collects all the deoxygenated blood from smaller veins to the heart (right atrium). The Anterior Vena Cava collects blood from the Jugular and Subclavian Veins, while the Posterior Vena Cava collects blood from the lower body.

19. 12. Pulmonary Veins and Arteries: The Pulmonary Circuit is comprised of the pulmonary trunk and arteries that deal strictly with the heart and the lungs. The Systemic Circuit services oxygenated blood to the body tissues. Only Artery in the body that carries deoxygenated blood. Only Vein in the body that carries oxygenated blood.

20. Function: The artery brings deoxygenated to the lungs to get oxygen for the body, while the vein returns oxygenated blood to the Left Atrium.

21. PULMONARY AND SYSTEMIC CIRCULATION

22. Pulmonary Circuit: --Path that goes to and from the lungs. --From right ventricle through the pulmonary trunk --> pulmonary arteries--> Lung capillaries --> Pulmonary Veins --> Left atrium. --Carries carbon dioxide filled blood to lungs for cleaning. --Returns oxygen rich blood to heart.

23. Systemic Circuit: -- Path from Left Ventricle to body back to right Atrium of heart. -- Carries oxygen rich blood to body tissues. -- Returns carbon dioxide filled blood to heart.

24. FETAL CIRCULATION SYSTEM Fetal systems have FOUR features not present in Adult Systems: 1. OVAL OPENINGS -- An opening between the 2 atria. -- It is covered by a flap of tissue that acts like a valve. -- Blood flows directly from the right atrium to the left atrium. -- Bypassing the lungs, which do not work yet.

25. 2. ARTERIAL DUCT -- A connection between the Pulmonary Artery and the Aorta. -- Blood flows from the Pulmonary Artery to the Aorta, again bypassing the lungs.

26. 3. UMBILICAL ARTERY AND VEIN -- Umbilical Artery takes waste (Carbon Dioxide and Urea ) to the Placenta. -- Umbilical Vein takes nutrients (Oxygen and Glucose and Amino Acids) to the Fetus from the Placenta.

27. 4. VENOUS DUCT -- A connection between the Umbilical Vein and the Vena Cava. --Blood from the placenta passes directly into the liver through this duct and from there, to the right atrium of the heart.

29. PATH OF A BLOOD CELL THROUGH THE BODY Start in the Left Ventricle and go through the Circulatory System

30. COMPONENTS OF BLOOD A. Plasma: 55 % of blood B. Formed Elements: 45% -- Erythrocytes (RED BLOOD CELLS) -- Leukocytes (WHITE BLOOD CELLS) -- Thrombocytes (PLATELETS)

31. FEATURERED BLOOD CELLSWHITE BLOOD CELLSPLATELETS SHAPEBiconcaveVariable, AmoeboidTiny, Cell fragments FUNCTIONTransportCombat infectionBlood clotting ORIGINBone marrow Lymphoid Tissue Bone Marrow ALSO CALLEDErythrocytesLeukocytesThrombocytes

32. NAMEFUNCTION A. Water (90%)Blood Volume Transport of cells and materials B. Plasma Proteins Helps maintain Osmotic pressure in blood. a) Albumen-Transports b) Fibrinogen-Blood Clotting c) Globulins-Infection fighting C. Gases a) Oxygen-For respiration b) Carbon Dioxide-Waste D. NutrientsEnergy source - Raw materials for the body a) A.A. Glucose, Fatty acids, Glycerol E. Salts Osmotic Pressure Helps in Metabolism F. Wastes Waste production of Cellular Reactions. CONSTITUENTS OF PLASMA

33. SHAPE, FUNCTION AND ORIGIN OF BLOOD CELLS 1. RED BLOOD CELLS—Erythrocytes -- Live about 120 days -- Produced in Red Bone Marrow (In Skull, ribs, vertebrae, and long bones.) --Myeloid stem cells form RBC. These stem cells are called Erythroblasts. Erythroblasts will differentiate into Erythrocytes. -- Produces about 5 million every second. -- RBC contains a protein called HEMOGLOBIN.

34. -Hemoglobin contains iron (gives blood its red color). -Picks up oxygen in the lungs (cooler blood) -It combines with oxygen in lungs and releases it in the warmer tissues. -Approximately 200, 000, 000 hemoglobin molecules in one RBC -If Hemoglobin was not packaged up in RBC, Oxygen would leak out of circulatory system. -RBC allow the blood to remain liquid so the heart does not have to work as hard. -Destroyed in the liver and spleen.

35. LUNGS BODY Cooler less acidic Warmer more acidic Causes Hemoglobin (HG) to pick up oxygen. (HG) to drop off oxygen.

36. 2. WHITE BLOOD CELLS – Leukocytes -- Larger than RBC -- They have nucleus (RBC do not) -- Less numerous than RBC (700:1) -- Do not have a definite shape. -- Function: Fights against infection: 1) Phagocytic 2) Produce Antibodies

37. Types of White Blood Cells Granulocytes -Have grains or granules in their cytoplasm. -Formed in Bone Marrow. -60 – 70 % of Leukocytes (WBC) are Ganulocytes. Example: NEUTROPHIL – Phagocytize and digest bacteria. Agranulocytes - No granules in cytoplasm - Produced by lymphoid tissue. - 25-30 % of Leukocytes (WBC) Example: Monocytes and Lymphocytes

38. Lymphocytes: 1) B-Lymphocytes-Produced in the bone and lymphoid tissue. T-Lymphocytes- Produced in the Thymus and give rise to plasma cells Monocytes: 1) Largest WBC 2) Take up residence in tissues Differentiate into larger macrophages which phagocytize microbes and stimulate other WBC

40. 3.PLATELETS (Thrombocytes) -- Produce 2 billion a day. -- Broken fragments of larger cells. -- Very important role in blood clotting Blood Clotting- Need three things in blood 1) Prothrombin 2) Fibrinogen 3) Platelets - Platelets clump at the site of the “leak” and partially close it. - The platelets and the injured tissue together release an enzyme called THROMBOPLASTIN.

41. - Thrombolplastin converts a blood protein (prothrombin) (produced by the liver) to a new substance called THROMBIN. Calcium is needed for this to occur. Prothrombin (activator protein) is made up of Potassium. If potassium is missing from diet, then it can cause hemorrhaging disorders to occur. -Thrombin acts as an enzyme that breaks the ends off another blood protein called FIBRINOGEN. (also produced by the liver)

42. - Fibrinogen is then converted into FIBRIN - Fibrin has sticky ends and forms a lattice or network over the leak. Blood cells get trapped and form a clot. - Fibrin clot is only temporarily present. As soon as the blood vessel repair is initiated, an enzyme called Plasmin destroys the network.

44. RBC trapped in the FIBRIN network

45. ABO Blood System Blood GroupProteins on Red Blood Cells (Antigen) Clumping Chemicals in Plasma (Antibody) Can Accept Transfusions from Group(s) AAAnti BA, O BBAnti AB, O ABA and BNoneA, B, AB, O ONoneAnti A Anti BO

46. Red blood cells may have another antigen called antigen D. This is known as the Rhesus Factor. This distinguishes blood as being RH+ or RH-. Therefore there are 8 possible blood types. If mother is RH- and father is RH+ then baby has a chance of being RH+. This could be a concern

48. RH factor plays a role in childbirth. If RH- mother is carrying a RH+ baby then the situation has to be monitored. Baby’s blood comes in contact with mom’s. The antigen D in baby’s blood would be perceived as foreign and mother would try and destroy the baby’s Red blood cell by producing antibody D. This is known as ERYTHROBLASTOSIS.

49. Mother and child would be fine, but next birth there would be a problem. If second baby is RH+ then agglutination would occur and the baby will be in trouble. This is why doctors would strongly suggest mothers not to have more children after the first RH+ baby. It still has to be monitored today, but RHOgan (an enzyme) can be injected into Mom, which eliminates antibody D.

50. LYMPHATIC SYSTEM Functions: 1. Takes excess tissue fluid and sends it to the circulatory system. The Lymphatic system joins the Circulatory System at the subclavian veins. 2. Products of fat digestion are absorbed into Lacteals, which lead to the Lymph Vessels and Nodes. 3. Lymph Nodes produce Lymphocytes. ( A type of White Blood Cell) 4. Lymph Nodes act as filters and trap bacteria and other debris. (helps to purify the body fluids)

51. Examples: Spleen: -Largest lump of Lymphatic Tissue. -Produce Lymphocytes and stores excess blood. -If your blood pressure is high, it stores blood so that blood pressure lowers. -If your blood pressure is low, it contracts and adds blood, so that blood pressure rises. Thymus Gland: -Bi-lobed structure which is important in the maturing of some Lymphocytes. -Becomes smaller with age. Tonsils and - Also contain Lymphoid tissue Appendix - Thought to help remove invading organisms and viruses. Lymphatic Tissue - Produce lymphocytes and stores excess blood.

52. STRUCTURES IN THE LYMPHATIC SYSTEM Lymph Vessels: Similar to veins, but fluids only travel in one direction. Contain lymph veins and capillaries, but NO Lymph Arteries. Lymph Nodes: Small oval or round tissues which filter fluids and produce Lymphocytes. Lacteals: Blind sacs in villi of Digestive System which absorb products of Fat Digestion.52

53. INFECTION FIGHTING –Inflammatory Response 1) - Foreign substance (bacteria or viruses) attacks - Monocytes and Neutrophils engulf the bacteria or viruses in amoeboid fashion (Phagocytosis). - These WBC are able to travel to the site of the infection through the capillary network. - Dead tissue, cells, bacteria, dead and living neutrophils all together make up PUS.

54. 2) Lymphocytes -- Produce antibodies. -- One antibody fights a specific antigen (foreign protein). -- Antigen + Antibody --> Inactive complex. Antigens – A Protein found in the outer membrane of blood -- The type of protein determines the type of blood Antibodies - A protein that attacks unwanted proteins. - End result is agglutination

56. CAPILLARY FLUID EXCHANGE Blood is oxygenated as it passes through lung tissue. Oxygen (higher in concentration in the inhaled air) diffuses through the thin walled tissues of the lung to capillaries and into the blood where it bonds to hemoglobin (the iron containing protein that is part of the RBC). A single hemoglobin molecule has four bonding sites for oxygen and is called oxyhemoglobin when transporting oxygen.

57. The blood reaches arterioles and then the capillaries. Blood pressure has decreased. Nutrients (products of digestion) and oxygen diffuse into the tissues. The larger particles in blood stay where they are too big to get out. Because of these large molecules, the blood is said to be hypertonic to the tissues. As a result, the water from the tissues is drawn back into the venule side of the capillary bed. When the fluid returns it carries carbon dioxide and wastes with it.

58. Blood pressure on arteriole side of capillary is higher than osmotic pressure and will try and push substances out of blood. Osmotic pressure pushes substances into blood and since blood pressure is greater than osmotic pressure, Oxygen, glucose and water are taken from blood and put in the tissues. Blood pressure on the arteriole side of capillary is lower than the osmotic pressure and therefore wastes such as Carbon dioxide, ammonia and water forced into the blood.