The Circulatory System.pptxSDFGHJKLASDFGHJ

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1. The Circulatory System

2. Learning Targets: At the end of the lesson the students can be able to: - identify and described the structure of the organs and issues composing the cardiovascular system - trace the flow of the blood in cardiovascular system.

3. Can you imagine what can happen when the heart rests?

4. Function of Circulatory System Circulates OXYGEN and removes Carbon Dioxide. Provides cells with NUTRIENTS.

5. Removes the waste products of metabolism to the excretory organs for disposal. Protects the body against disease and infection. Clotting stops bleeding after injury.

6. The Circulatory System is divided into three major parts: The Heart The Blood Vessels The Blood

7. One of the most amazing and most complex organs in the body. It is highly muscular organ and is the size of our fist. The Heart and Blood Vessels

8. It pumps blood throughout the body by way of involuntary contractions of the cardiac muscle. The heart is located in the center of the thoracic or chest cavity, slightly toward the left.

9. The right atrium receives oxygen-poor blood from the body and pumps it to the right ventricle. The right ventricle pumps the oxygen-poor blood to the lungs.

10. The left atrium receives oxygen-rich blood from the lungs and pumps it to the left ventricle. The left ventricle pumps the oxygen-rich blood to the body.

11. Four Valves of the Heart

12. The four valves help maintain the proper blood flow through the heart.

13. The tricuspid valve is between the right atrium and right ventricle. They often and close with precise timing to make the heart pump blood effectively.

14. The tricuspid and the bicuspid valves are called atrioventricular (AV) valves , meaning they are located between the atrium and ventricle.

15. The bicuspid valve or mitral valve is located between the left atrium and left ventricle.

16. The pulmonary valve lies between the right ventricle and the pulmonary artery, which takes blood to the lungs

17. The aortic valve lies between the left ventricle and the aorta. This valve (aortic valve) prevents blood from entering the aorta prematurely.

18. The aortic valve opens when the ventricle contract, allowing blood to move from the heart and start the journey to the rest of the body.

19. The heart needs passageway to distribute blood throughout the body. These passageway are the:

20. The arteries carries blood away from the heart and generally transport oxygen-rich (oxygenated/carbon dioxide poor) blood

21. Capillaries connect arteries and veins. This is where the gas exchange between the blood and the tissues takes place

22. Capillaries then merge into venules then into larger channels called veins . Veins - carry blood to the heart and generally transport oxygen-poor, carbon dioxide rich blood .

23. The Blood Avery vital red fluid (blood) that flows through our blood vessels, provide oxygen and nourishment to our body cells This red fluid (blood) also take away carbon dioxide and waste product from our body cells.

24. It also helps maintain body temperature and controls pH . Blood is transported to the different parts of our body by the circulatory system.

25. Blood is composed mainly of : a) Plasma - the yellowish liquid that is composed of 90% water that carries nutrients, hormones, and other important substances

26. b) Different blood cells:

27. The Red Blood Cells (RBC) The red blood cells, also known as erythrocytes , carry oxygen to the cells.

28. After transporting oxygen to the cells, red blood cells collect the waste gas (carbon dioxide, the by-product of cellular respiration) and transport it back to the lungs, where carbon dioxide is expelled from the body as we exhale.

29. The red blood cells are the most abundant of the blood cells (around 5,000,000 red blood cells in drop of blood) and its lifespan is 120 days.

30. The red blood cells are red in color because they contain hemoglobin . Hemoglobin contains iron (Fe) making it an excellent transporter of oxygen and carbon dioxide.

31. The White Blood Cells (WBC) The white blood cells , also known as leukocytes , battle infection, attack and destroy germs or foreign proteins that enter the body.

32. There are about 7,000 WBCs per milliliter of blood (mL) and this number can be used as an indicator of a disease. During infection, the body produces more white blood cells to help fight off the infection.

33. Several types of white blood cells:

34. Several types of white blood cells: Neutrophil combats bacterial and fungal infection b) Eosinophil defends against parasitic infections c) Lymphocytes B-cells make antibodies to fight the foreign protein and T-cells function in immune response.

35. d) Monocytes remove dead cells debris and clean up the “crime scene” where the body’s soldiers battle an infection. e) Basophil functions during allergic and antigen (foreign protein reactions.

36. Platelets Platelets, also known as thrombocytes , help the blood clot, thereby preventing bleeding when an artery or vein is severed or broken.

37. Blood clotting is a temporary solution to stop bleeding. The lifespan of a platelet is from five to nine days only. A normal platelet count of a healthy individual is from 150,000 to 450,000 per milliliter of blood

38. Plasma Blood plasma is the pale, yellow fluid where the blood cells are suspended. Plasma makes up more than half of the total blood volume, roughly 55%.

39. Plasma also plays a very important role in osmosis, thereby promoting the balance of electrolytes Blood serum is blood without the blood cells and the clotting factors

40. Human Circulatory Paths The circulatory system has two distinct paths, the pulmonary circuit and the systemic circuit. Although they are two distinct path, they actually occur simultaneously and not in a sequential manner. Both side of the heart work together.

41. Human Circulatory Paths Pulmonary circulation can be summed up as the part of the circulation that carries oxygen-poor blood to the lungs and bring back oxygen-rich blood to the heart.

42. Blood enters the pulmonary circuit when the right atrium receives oxygen-poor (carbon dioxide-rich) blood from body tissues through the superior vena cava and the inferior vena cava.

43. As the blood leaves for the pulmonary circuit, some of the blood move through the systemic circuit. The superior vena cava receives blood from the upper part of the body , and the inferior vena cava receives blood from the lower part of the body .

44. The blood passes through the tricuspid valve into the right ventricle. From the right ventricle, the deoxygenated blood is pumped out from the heart through the pulmonary tract that splits into the right and left pulmonary arteries going to the lungs for oxygenation.

45. Carbon dioxide in the blood diffuses into the lungs to pick up fresh load of oxygen. At this point, blood is now oxygen-rich (carbon dioxide-poor). From the lungs, the blood returns to the heart by way of the right and left pulmonary veins. Pulmonary circulation end when oxygenated blood returns to the heart

46. Systemic Circulation Systemic circulation is the movement of oxygenated blood from the heart for distribution throughout the body and bringing in of deoxygenated blood to the heart.

47. Oxygenated blood enters the left atrium, then the blood passes through the mitral or bicuspid valve and into the left ventricle.

48. With the great pressure, the oxygenated blood from the left ventricle is pumped into the aorta, the biggest artery in the body, to be distributed throughout the body via a network of blood vessels.

49. The aorta branches into smaller arteries, then into arterioles and finally into capillaries. Waste and carbon dioxide diffuses out of the cells and into the blood, the oxygen diffuses out of the blood and into the cells.

50. The blood is now carbon dioxide-rich and oxygen-poor.

51. This deoxygenated blood then continues its travel and the capillaries merge into venules then to larger veins and finally into the superior and inferior vena cavas that drain into the right atrium of the heart.

52. STRUCTURE and FUNCTION: Working Together of the Different Organ Systems The circulatory system supplies food nutrients and oxygen that all the cells of a living body needs. In turn, it collects the metabolic wastes that body cells produce.

53. Such dual function of the circulatory system requires a systematic coordination with other organ system. To carry out its vital functions, it is imperative for the circulatory system to reach out to all organs of the body,

54. The Circulatory System and Digestive System Most of the digested foods are absorbed in the intestinal villi . Intestinal villi is the tiny fingerlike projections at the lower portion of the small intestine. Each villus is provided with two kinds of vessels: capillaries and lacteals.

55. Molecules of simple sugars and amino acids diffuse into the capillaries and reach the blood. Molecules of fatty acids and glycerol diffuse into the lacteals and reach the lymph. At this point, the circulatory system takes over. The circulatory fluids, blood and lymph, distribute the digested foods to all cells of the body

56. The Circulatory System and the Excretory System The circulatory system plays a very important role in the excretion of metabolic waste products for our body. The circulating blood is responsible for collecting these waste products from all body cells and transporting them to various excretory organs through which particular wastes are expelled from the body. How does the circulatory system work with the kidneys , our body’s major excretory organs?

57. The renal artery brings blood with many impurities to the kidney. In the kidney, the renal artery subdivides into small arterioles that branch into a network of tiny capillaries making up the glomerulus , which is enclosed by the Bowman’s capsule.

58. As blood passes through the glomerulus, urine, water, glucose, and salt are filtered into the Bowman’s capsule. However, when the blood passes through the long convoluted tubules of the nephron, much of the water absorbed through the glomeruli is reabsorbed together with the salts, blood sugar, blood proteins and other substances needed by the body.

59. The liquid which remains in the tubules is now called urine. This excretory waste is passed on from the kidney to the ureter and to the urinary bladder for temporary storage. As urine fills up the urinary bladder, it becomes heavier and heavier until the sphincter muscle that closes the opening of the bladder relaxes and the smooth muscles of the bladder contracts, expelling the urine through the urethra and out of the body.

60. How does the circulatory system work with other excretory organs? The liver cells change amino acids, through the series of chemical reactions, into urea. Urea, the nitrogenous waste is then transported by the blood from the liver mostly to the kidney where it is filtered out of the blood and expelled as part of the urine.

61. The liver also breaks down old blood cells. Most of the iron salts from the blood cells are brought back to the bone marrow by the blood.

62. The rest of the broken blood cells become part of the bile which helps in fat digestion. Urea is also transported by the blood from the liver to the sweat glands of the skin where it is expelled as part of sweat, another excretory waste.

63. The Circulatory System and the Nervous System The nervous system works with the circulatory system mainly in the heart by controlling the flow of blood in the different chambers of the heart.

64. The nervous system controls the “electrical relay system” in the heart by opening or closing chambers of the heart to ensure that blood travels out of the left ventricles into the rest of the body.

65. The muscle of the heart and that of the blood vessels are called involuntary muscle because they are not under the control of our will. Their action are governed by the autonomous nervous system through the sympathetic and parasympathetic nerves whose actions are opposite each other.

66. A sympathetic nerve makes the heart beat faster while a parasympathetic nerve slows down heart beat. Thus, the sympathetic and the parasympathetic nerves regulate and control each other’s activity to maintain homeostasis or the dynamic balance in the functioning of the heart.

67. The hypothalamus of the forebrain in the central nervous system plays another important role for homeostasis . Among its vital functions are to regulate blood pressure and to control the secretions of many hormones.

68. The Circulatory System and the Endocrine System Certain glands in the body release their secretions directly into the bloodstream instead of through tiny tubelike duct.

69. These tiny tube like duct are called ductless or endocrine glands . Their secretions are called hormones , are special protein substances that are present in small quantities in the body. They bring about changes in cells or tissues which are referred to as their “targets”

70. The effect of a hormone may be an increased activity or a decrease activity of the target cells. It may also be just plain maintenance of the cells.

71. Following are some examples of hormone actions involving the circulatory system 1.Adrenalin (adrenal gland hormone) increases blood pressure and heart rate and dilate blood vessels. 2. Insulin (a pancreatic hormone) lowers blood sugar level. 3. Parathyroid hormones raises blood calcium level.

72. The Circulatory System and Some Other Organ System The circulatory system depends on the skeletal system for the production of blood cells. The red blood cells are produced in the red marrow of flat bones (such as the ribs) and long bones (such as thigh bones)

73. Blood cells, including red blood cells, certain white blood cells and blood platelets are formed from special connective tissues referred to as hemocytoblasts.

74. The circulatory system and the muscular system keep each other healthy. The healthier and more active the muscular system is, the healthier the circulatory system. Active muscles demand a greater amount of oxygen and nutrients for energy source and repair of worn-out tissues.

75. The heart pumps harder to enable the blood to provide these needs. Blood also collects waste products from the hardworking muscles and carries them to their respective excretory organs.

76. If the circulatory system fails to supply the necessary requirements, the muscles will cramp and eventually become dysfunctional. Long-term inactivity of the muscles is detrimental to the overall health of the cardiovascular system.

77. The heart will weaken and lose mass while the blood vessels serving the muscles will atrophy or shrink along with the muscles themselves. On the other hand, enough and regular exercise increases the mass of body muscles over time. The heart muscle strengthen and the size of the blood vessels connected to the active body muscles increases as well.