1. Circulation & Respiration Chapter 42

3. Circulatory systems 2 types Open circulatory system
Mollusks & arthropods
No distinction between blood & lymph
Flow through a network of vessels
Hemolymph
Circulating fluid

4. Circulatory systems Closed circulatory system Vertebrates Blood
Enclosed in blood vessels & heart
Lymph
Lymph system
Interstitial fluid

5. CLOSED CIRCULATORY SYSTEM
OPEN CIRCULATORY SYSTEM

6. Functions 1. Transportation Substances needed for cellular respiration
A. Respiratory
CO2 and O2
B. Nutritive
glucose
C. Excretory
Metabolic wastes, ions, water

7. Functions 2. Regulation 3. Protection Hormones
Temperature regulation (Endotherms)
Vessels constrict cold
Vessels dilate hot
3. Protection
Clotting
Proteins, platelets
Immune defense
WBC, AB

8. Components of the system
Heart
Blood vessels
Blood

9. Heart Fish 2 chambered Amphibians/some reptiles 3 chambered
Cutaneous circulation:
Oxygen diffuses in from environment
Birds/mammals 4 chambered
Separation of systemic & pulmonary blood systems

10. Circulation

11. Heart Systemic circulation: Blood flow in the body
Pulmonary circulation:
Blood flow between the heart & lungs

12. Circulation

13. Heart structure Atrium Small chambers Receive blood Ventricles
Larger chambers
Pump blood from heart
Septum
Separates chambers

14. Septum

15. Heart structure Valves Atrioventricular valves (AV)
Between the atrium and ventricles
Tricuspid is on the right
Bicuspid or Mitral is on the left
Semilumar valves
Exits from the ventricles
Aortic valve (L ventricle)
Pulmonary valve (R ventricle)

16. Valves

18. Heart structure Heart sounds “lub-dub” -valves closing
“lub” closing of the AV valves
“dub” closing of the semilunar valves
Murmur:
Abnormal heart sound
Harsh sound of blood flowing over valve

19. Heart structure Superior & inferior vena cava
Brings blood to heart from body
Pulmonary arteries
Blood from right side of heart to lungs
Pulmonary veins
Returns blood from lungs to heart
Aorta
Blood goes from the heart to body

20. Circulation

21. Blood flow
E:\Chapter_42\A_PowerPoint_Lectures\42_Lecture_Presentation\42_06PathOfBloodFlow_A.html

22. Blood flow Vena cava Right atrium Tricuspid valve (AV) Right ventricle
Pulmonary valve (semilunar)
Pulmonary artery
Lungs

23. Blood flow Pulmonary veins Left atrium Mitral valve (AV)
Left ventricle
Aortic valve (semilunar)
Aorta

24. Blood flow

25. Blood flow Cardiac cycle: One cycle of heart filling & emptying
Diastole
Heart resting
Heart filling with blood
AV valves open
Semilunar valves closed

26. Diastole

27. Blood flow Systole Ventricles contracting
Pumping blood out of the heart
AV valves closed
Semilunar valves open

28. Systole

30. Blood pressure Measurement of pressure of blood in the arteries
Systolic measures ventricular contraction
Diastolic measures ventricular resting
Sphygmomanometer or BP cuff
Brachial artery
120/80 normal

31. Blood pressure

32. Cardiac output
Volume of blood pumped by the left ventricle into systemic circuit per minute
5 liters per minute
Depends on heart rate
Stroke volume
Amount of pumped out per contraction (70 ml)

33. Cardiac output Increases with exercise Increased HR
Better stroke volume

34. Blood pressure Cardiac output Flow resistance in the arteries
Affect BP
More constriction higher BP
More dilation lower BP
Baroreceptors
Aorta & carotids
Medulla oblongata

35. Blood pressure Depends on blood volume Decreased volume
Decreased cardiac output
Decreased BP

36. Heart structure Coronary arteries First branches off the aorta
Supply blood to the heart

37. Coronary arteries

38. Conduction Depolarization of heart muscle stimulates contraction
Heart contains autogenic cells
Self stimulate
SA node (sinoatrial)
Pacemaker of the heart
Located in R atrium wall
Near the superior vena cava

39. Conduction SA node Causes atrium to contract
Sends signal to the AV node
AV (atrioventricular) node
Located in wall between R atrium & ventricle
Sends signal to the bundle of His

40. Contraction Bundle of His Sends signal to the Purkinje fibers
Cause the ventricle to contract
SA⇨AV⇨Bundle of His⇨Purkinje fibers

42. Conduction

43. Conduction

44. EKG Electrocardiogram Records electrical impulses of the heart P-wave
First wave-atrium contraction
QRS-wave
Ventricles contracting
T-wave
Heart re-polarization

45. EKG or ECG

46. Vessels Arteries, arterioles Veins, venules Capillaries
arteries⇨arterioles⇨capillaries⇨venules⇨veins

47. Capillaries

48. Blood vessels

49. Vessels Basic structure (except capillaries)
Inner layer is endothelium
Next is a layer of elastic fibers
Smooth muscle layer
Connective tissue
Capillaries are single cell layer thick
Endothelium only

50. Arteries Carry oxygen rich blood away from heart Arterioles:
Smaller arteries
Larger the artery
More elastic & recoil as blood is pumped

51. Arteries Vasoconstriction: Contraction of smooth muscle in arterioles
Decrease blood flow
Vasodilation:
Relaxation of smooth muscle
Increase blood flow
Precapillary sphincters:
Regulate blood flow

52. Veins Carry oxygen poor blood to heart Venules Smaller veins
Less smooth muscle
Skeletal muscles constrict
Help flow of blood to heart
Venous valves:
Help blood flow to heart prevent backflow

53. Varicose veins
Too much blood in legs
Valves veins do not work

54. Capillaries Passage of oxygen & nutrients
Into cells or extracellular fluids
Passage of carbon dioxide & wastes
From cells to blood

55. Blood

56. Blood Plasma (matrix) yellow Fluid part of the blood
Metabolites, wastes, hormones
Ions (sodium, chlorine, bicarbonate)
Proteins
Albumin (fluids), globulins (antibodies), fibrinogen (clots)
Cells
RBC, WBC, platelets

57. Blood cells

58. Blood formation

59. RBC Erythrocyte O2 & CO2 transport Hemoglobin (protein) Erythropoietin
Hormone secreted by kidney that stimulates RBC production
Erythropoiesis
Process of RBC production from stem cells
Spleen, bone marrow & liver remove RBC

60. Heme

61. Hemoglobin

62. RBC

63. WBC Leukocyte Larger than RBC Contain a nucleus
Fights against infection and FB
Interstitial fluid as well as blood
5 types of WBC split into 2 groups
Granulocytes: neutrophils, eosinophils, basophils
Non-granulocytes: lymphocytes, monocytes

64. WBC

65. Platelets Cell fragments Megakaryocyte
Large cell in bone marrow that forms platelets
Clotting
First to site of injury
Fibrin (protein that forms clot)

66. Platelets

67. Clotting Tissue damage Platelets arrive Cascade reactions are started
Prothrombin is changed to
Thrombin (enzyme)
Changes fibrinogen to fibrin
Forms clot

68. Fibrin

69. Blood More RBC than WBC Hematocrit Measurement of RBC’s in the blood
RBC last about 120 days

70. Lymph system Interstitial fluid
Fluid from the blood plasma that leaves the capillaries
Surrounds the tissues
Lymph:
Returns to circulation via lymph system
Lymph nodes, lymph vessels & organs (spleen & thymus)

71. Edema Swelling of tissues Usually ankles or feet
Interstitial fluid cannot be returned
Low protein (albumin)
Liver disease
Heart disease
Pregnancy

72. MI

73. Flutter

74. Atherosclerosis

75. Aneurysm

76. Infarct

77. Pacemaker

78. VSD

79. MVP