Chapter 12 A&P

  1. Circulatory system divsions
    • Pulmonary Circuit
    • Systemic circuit
  2. Pulmonary circuit
    Carries blood to and from the lungs
  3. Systemic circuit
    Transports blood to and from the rest of the body
  4. Arteries carry blood?
    Away from the heart
  5. Capillaries are?
    Tiny vessels between the smallest arteries and the smallest veins
  6. Four chambers of the heart?
    • Right atria
    • Right ventricle
    • Left atria
    • Left ventricle
  7. The heart is surrounded by?
    Pericardial cavity
  8. The _____ ______ covers the hearts outer surface and the _____ _____ is the opposing lining
    • Viseral pericardium
    • Parietal pericardium
  9. The coronary sulcus is?
    A deep groove that marks the boundary between the atria and the ventricles
  10. The myocardium is?
    Muscular bulk of the heart
  11. The endocardium ?
    Lines the inner surfaces of the heart
  12. Cardiac muscle cells are interconnected by _______ _______ which convey the force of contraction fr cell to cell and conduct action potentials
    Intercalated Discs
  13. Interatrial Septum
    Separates atria
  14. Interventricular Septum
    Divides the ventricles
  15. Superior and Inferior Vena Cava
    Lg veins from the systemic circuit delivering blood to the rt atrium
  16. Rt Atrioventricular Valve (AV) aka _____?
    • Blood flows fromt the R atria into the R ventricle through this valve.
    • aka tricuspid
  17. The R AV opening is bounded but 3 ______ of fibrous tissue braced by tendinous ______ ______ which are connected to _______ _______.
    • Cusps
    • Chordae Tendonae
    • Papillary Muscles
  18. Pulmonary Semilunar Valve
    Blood leaving the rt ventricle enters the pulmonary trunk after passing through here
  19. The 2 divisions of the pulmonary trunk are?
    Left and Right pulmonary arteries
  20. Left and Right pulmonary veins
    Return oxygenated blood to the left atrium
  21. Left atrioventricular valve (AV) and aka's
    • Blood leaving the left atrium flows into the left ventricle through here
    • AKA's --- bicuspid valve or mitral valve
  22. Aortic semilunar valve
    Blood leaving the left ventricle passes through here and into the systemic circuit through the aorta
  23. Due to functional demands what makes the ventricles different?
    The wall of the right ventricle is relatively thin whereas the left ventricle has a massive muscular wall
  24. Regurgitation
    Backflow of blood prevented by by one way valves
  25. Fibrous Skeleton
    Encircles the valves and vessels of the heart and stablizes them
  26. Coronary Arteries & What R & L supply
    • Originate at the base of the aorta at the aortic sinuses
    • RCA supplies R atrium and portions of the ventricles
    • LCA supplies L ventricle, L atrium, interventricular septum
  27. Anastomoses
    Interconnections between the branches of the LCA & RCA that provide alternate pathways for blood supply to reach cardiac muscle.
  28. 2 branches of the RCA
    Marginal and Posterior interventricular branches
  29. 2 branches of the LCA
    Circumflex and anterior interventricular branches
  30. Great and Middle cardiac Veins
    carry blood away from the coronary capillary veins and drain into the coronary sinus
  31. Coronary sinus
    Lg thin walled vein in the posterior portion of the coronary sulcus
  32. Two general classes of cardiac cells are involved in the normal heartbeat?
    • Contractile Cells
    • Cells of the conducting system
  33. Contractile Cells
    Form a bulk of the hearts muscle tissue and produce powerful contractions that propel blood
  34. Conducting System
    Ctrl and coordinate activities of the contractile cells
  35. Nodal Cells
    • Conducting sys cells the establish rate of cardiac contraction.
    • Pacemaker cells are nodal cells that reach threshold 1st
    • Located in the sinoatrial and atrioventricular nodes
  36. Conducting Cells
    • Distribute the contractile stimulus to the general myocardium
    • Locations include AV bundle, bundle branches and purkinje fibers
  37. Progression of Cardiac Conduction Electrically
  38. SA node--> Internodal--> AV Node--> Bundle --> L & R -->Purkinje
    • of His Bundle Fibers
    • Branches
  39. Electrocardiogram
    Recording of electrical activities in the heart
  40. P Wave
    Atrial depolarization
  41. QRS Complex
    Ventricular depolarization
  42. T Wave
    Ventricular repolarization
  43. The 2 parts of a cardiac cycle are?
    • 1. Systole -- Heart contraction
    • 2. Diastole-- Heart relaxation
  44. Heart sounds like?
    Lupp Dupp -- closing of the heart valves
  45. Stroke Volume
    Amt of blood ejected by a ventricle during a single beat
  46. Cardiac Output
    Amt of blood pumped by each ventricle each minute
  47. 3 major factors affecting cardiac output?
    • 1. blood volume reflexes
    • 2. autonomic innervation
    • 3. hormones
  48. Venous Return
    • Amt of blood that enters the heart
    • Changes in stimulate blood volume reflexes
  49. Atrial Reflex
    Accelerates the HR when entering blood stretches the walls of the R atrium
  50. Frank-Starling Principle Says?
    Ventricular contractions become more powerful & increase stroke volume when ventricular walls are stretched
  51. Basic HR is established by _____ _____ but can be altered by the _____
    • Pacemaker Cells
    • ANS
  52. ACh released by the parasympathetic motor neurons does what to HR and stroke volume?
    Lowers it
  53. NE released by sympathetic neurons does wht to HR and stroke volume?
    Increases it
  54. E and NE released by the ____ ____ during ____ ____ increase both HR and stroke volume. These 2 also act to increase cardiac output
    • Adrenal Medullae
    • Sympathetic Activation

    • Thyroid hormones
    • Glucagon
  55. Cardioacceleratory Center is located in, activates & receives inputs fr?
    • Medulla Oblongata
    • Sympathetic Neurons
    • Receives inputs fr higher ctrs & fr receptors that monitor BP & disolved gasses
  56. Cardioinhibitory Center does what?
    • Governs activities of parasympathetic neurons
    • Receives inputs fr higher ctrs & fr receptors that monitor BP & disolved gasses
  57. The blood supply to the muscles of the heart is provided by
    Coronary circulation
  58. The autonomic centers for cardiac function are located in
    Cardiac centers in the medulla oblongata
  59. The simple squamous epithalium that covers the valves of the heart constitutes the
  60. Blood leaves the L ventricle by passing through the
    Aortic semilunar valve
  61. The QRS complex of the ECG is produced when
    Ventricles depolarize
  62. During diastole the chambers of the heart
    Relax and fill with blood
  63. What roles do chordae tendineae and papillary muscles have in normal function of the AV valves?
    During ventricular contraction, tension on the papillary muscles pulls against the chordae tendoneae keeping cusps of AV valve fr swinging into the atrium preventing backflow or regurgitation into the atrium as ventricle contracts
  64. What are the principle heart valves and what is their function?
    • Tricuspid (R AV) Prevents backflow of blood fr ventricles into atria
    • Bicuspid (mitral or L AV) Prevents backflow of blood fr ventricles into atria
    • Pulmonary & aortic semilunar Valves - prevents backflow of blood fr
    • pulmonary trunk & aorta into R & L ventricles
  65. Normal path of elec impulse through the conducting system of the heart
    SA node--> AV Node--> Av Bundle (bundle of his)--> R & L bundle branches--> Purkinje Fibers--> mass of ventricular muscle tissue
  66. What is the cardiac cycle?
    Complete heartbeat including a contraction/relaxation period for both the atria & ventricles
  67. Steps in the complete the cardiac cycle (blood flow through the heart)
    superior/inferior vena cava-->R atria-->Tricuspid valve-->R Ventricle-->Pulmonary semilunar valve-->pulmonary artery-->Lungs-->L atria-->bicuspid-->L ventricle-->aortic semilunar valve-->aorta-->body
  68. Tetanic muscle contractions cannot occur in a normal cardiac muscle cell b/c?
    the refractory period lasts until the muscle cell relaxes
  69. The amt of blood forced out of the heart depends on
    • Degree of stretching at the end of ventricular diastole
    • Contractility of the ventricle
    • Amt of pressure required to eject blood
  70. Cardiac output cannot increase indefinitely because
    Available filling time becomes shorted as the HR increases
  71. Describe the relationship of the four chambers of the heart to the pulmonary and systemic circuits
    R atrium receives blood fr systemic circuit & passes it to R ventricle which discharges it into the pulmonary circuit.

    L atrium collects blood & passes it to the L ventricle which upon contraction ejects it inot the systemic circuit
  72. What effect does sympathetic stimulation have on the heart?
    Causes release of NE by postganglionic fibers & secreation on NE & E by the adrenal meduleae. These hormones stimulate metabolism of cardiac muscle cells & increase force & degree of contraction
  73. What is the effect of parasympathetic stimulation on the heart?
    Causes release of ACh @ membrane surfaces producing hyperpolarization & inhibition resulting in decreased HR & force of cardiac contractions
  74. What r the lubb dupp sounds of the heart telling
    • Lubb--1st sound--Start of ventricular contraction & results fr AV valves
    • closing & semilunar valves opening

    • Dupp--2nd sound--Semilunar valves close marking start of ventricular
    • diastole
  75. Damage to semilunar valves on R side of the heart would interfere w blood flow to which vessel?
    Pulmonary artery
  76. What prevents AV valves fr opening back into the atria?
    Papillary muscle contraction counteract the force that is pushing the valves upward
  77. Why is the L ventricle more muscular than the R ventricle?
    B/c L ventricle propels blood throughout the body whereas R ventricle only has to propel it a few cm's into the lungs
  78. Cardiac muscle not undergoing tetanus affects the function of the heart how?
    Longer refractory period prevents tetanus resulting in longer relaxation period which allows chambers to refill w blood
  79. If cells of the SA Node were not functioning HR would be affected by?
    Slowing HR b/c cells of the AV Node would act as pacemaker cells
  80. Y is it important for impulses fr atria to be delayed @ AV Node b/f passing into ventricles?
    If they werent delayed they would be conducted so quickly by bundle branches & purkinje fibers that ventricles would contract prior to being full of blood & the heart would be less efficient
  81. Is the heart always pumping blood when pressure in the L ventricle is rising?
    No. Blood does not leave t heart until enough pressure is generated to exceed pressure in t aorta forcing semilunar valves open and ejecting blood fr t ventricle
  82. What effect does stimulation of ACh receptors of t heart have on cardiac output?
    Stimulation of ACh receptors lowers HR & b/c cardiac output = stroke volume x HR cardiac output declines as well
  83. What effect does increased venous return have on stroke volume?
    Stroke volume would increase b/c venous return fills t heart w/ blood stretching t muscle invoking t Frank-Starling Principle
  84. How would increased sympathetic stimulation of t heart affect stroke volume?
    Increased sympathetic stimulation results in increased HR & increased force of contraction
  85. Angina Pectoris
    Severe chest pain resulting fr ischemia whenever hearts work load increases
  86. Cardiac Arrhythmias
    Abnormal patterns of cardiac elec activity that indicate abnormal contractions
  87. Cardiac Tamponade
    Condition resulting fr pericardial irritation & inflammation: fluid collects in pericardial sac restricting cardiac output
  88. Carditis
    Inflammation of the heart
  89. Coronary Arteriography
    Introduction of dye into 1 coronary artery thru a catheter resulting in an x-ray image of circulation called coronary angiogram
  90. Coronary Artery Bypass Graft (CABG)
    Routing of blood around an obstructed coronary artery by a vessel transplanted fr another part of t body
  91. Coronary Artery Disease (CAD)
    Disorder resulting fr obstruction of coronary circulation
  92. Coronary Ischemia
    • Deficiency of blood supply to t heart due to restricted circulation
    • May cause cardiac tissue damage & reduction in cardiac efficiency
  93. Coronary Thrombosis
    • Presence of thrombus (clot) in a coronary artery
    • May cause circulatory blockage resulting in a heart attack
  94. Echocardiography
    Ultrasound analysis of t heart & of blood flow thru the great vessels
  95. Electrocardiogram
    Recording of elec activities of t heart over time
  96. Heart Block
    Impairment of conduction in the heart which damage to conduction pathways disrupts hearts normal rhythm
  97. Heart Failure
    Condition where heart weakens & peripheraltissues suffer fr O2 & nutrient deprivation
  98. Miocardial Infarction
    Condition where blockage of coronary circulation causes cardiac muscle cells to die fr O2 starvation
  99. Pericarditis
    Inflammation of the pericardium
  100. Rheumatic Heart disease (RHD)
    Diasorder where heart valves become thickened & stiffen into a partially closed position& reduces efficiency of the heart
  101. Valvulver Heart Disease (VHD)
    Disorder caused by abnormal functioning of 1 of the cardiac valves
  102. Equation for calculating cardiac output
    • Cardiac Output = Stroke Volume x Heart Rate
    • mL/min mL/beat beats/min
Card Set
Chapter 12 A&P
Summary outline p463