Anatomy and Physiology 2 Exam 2

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Anatomy and Physiology 2 Exam 2
2011-03-19 07:53:03
Anatomy Physiology Terra

Anatomy and Physiology 2 Exam 2 Chap 20
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  1. What is the conducting system of the heart?
    • 1. Sinoatrial (SA) node
    • 2. Internodal pathways
    • 3. Atrioventricular (AV) node
    • 4. AV Bundle
    • 5. Bundle Branches
    • 6. Purkinje Fibers
  2. What are the electrical events associated with a normal electrocardiogram?
    • P wave-atrial depolarization
    • QRS complex-ventricle depolarization, atrial relaxation
    • T wave-ventricular repolarization
  3. What are the events of the cardiac cycle?
    • Systole
    • Diastole
  4. What is atrial systole and what sound is heard with it?
    • Atrium contraction to top off the volume in the ventricle
    • Sound-S4
  5. What is ventricular systole and what sound is heard with it?
    • Venticularr contraction and forces the blood upward and the AV valves close
    • The first heart sound is heard S1 or lub
  6. Cardiac output
    The aboutof blood pumped by each ventricle in one minute

    CO = HR x SV
  7. What is Ventricular Diastole?
    • Ventricular relaxation
    • The semilunar valves close
    • The second heart sound is heard S2 or Dup
  8. Stroke Volume
    blood ejected during ventricular systole

  9. End Diastolic Volume (EDV)
    at the completion of atrial systole each ventricle is full and the amount in both equal EDV

    Increase in HR=Shorter diastole=smaller EDV

    Increase in venous return=larger EDV and vice versa
  10. Ejection Fraction
    The percentage of the EDV represented by the SV

    EF = SV/EDV as a percent
  11. End Systolic Volume (ESV)
    the amount of blood remaining in each ventricle at the end of ventricular systole

    EDV - SV = ESV (End Systolic Volume)
  12. Preload
    Degree of stretch on the heart before it contracts
  13. Contractility
    the forcefulness of contraction of individual ventricular muscle fibers
  14. Afterload
    The pressure that must be exceeded before ejection of blood from the ventricles can occur
  15. Frank-Starling law of the heart
    The more the heart fills with blood during diastole, the greater the force of contraction during systole
  16. Contractility
    the strength of contraction

    Increase=positive inotropic agents-Promote Ca inflow-SNS (NE/E)

    Decrease=negative inotropic agents-Reduce Ca inflow- PNS takes over
  17. Afterload
    The pressure that must be overcome before the Semilunar valve will open

    Ejection of blood from the heart begins when pressure in rt. ventricle is greater than the pressure in the pulmonary trunk (20mmHg) and pressure in lt ventricle exceeds pressure in the aorta (80mmHg)

    Increase after load=decrease in SV
  18. What regulates HR?
    • Autonomic innervation
    • Hormones
    • Venous return
  19. Cardiac center
    autonomic headquarters for cardiac control
  20. Cardioacceleratory center
    Increase heart rate (SNS)
  21. Cadioinhibitory center
    slow the heart rate (PNS)
  22. Cardiac Reflexes
    • BP (barorecptors)
    • Oxygen levels (chemoreceptors)
  23. Autonomic Tone
    • Resting autonomic tone
    • Steady background levels of both divisions
  24. Pericardium
    • Protects the heart
    • Around the heart
    • Loose allow heart to move
  25. Fibrous pericardium
    • Outer layer
    • Prevents overstretching, protection, and anchoring
  26. Serous Pericardium
    inner thin membranous layer
  27. Parietal Pericardium
    outer serous membrane lining the cavity
  28. Visceral Pericardium
    • attached to the surface of the heart
    • Also called Epicardium
  29. Pericardial Cavity
    • filled with serous fluid
    • decreases friction acros surface tissues
  30. Myocardium
    • The cardiac muscle
    • Responsible for the pumping action of the heart
  31. Endocardium
    • the innermost layer
    • a thin layer of connective tissue covered by endothelium
    • continuous with the lining of the blood vessels
  32. Right Atrium
    Recieves de oxidized blood from the sstemic circulation
  33. Pectinate muscles
    Muscular Ridges
  34. Tricuspid valve
    • Atrioventricular valve
    • movement of blood from right atrium to right ventricle
  35. Right ventricle
    blood is pumped from the right ventricle into the pulmonary trunk through the pulmonary semilunar valves
  36. Chordae tendinae
    papillary muscles that hold the valve closed when the ventricle contracts
  37. Pulmonary circuit
    • left and right pulmonary arteries
    • branch repeatedly in lungs
    • at capillaries CO2 is exchanged for O2
    • Oxygenated blood dumped into left atrium
  38. Left Atrium
    receives blood from four pulmonary veins which ha just been oxygenated in the lungs
  39. Left atrioventricular valve
    • guards the entrance to the left ventricle
    • also called bicuspid valve/mitral valve
  40. Coronary circulation
    R and left coronary artery in the central sulcus get blood before any cell in the body
  41. Arterial Anastomoses
    Interconnection between arteries
  42. Coronary sinus
    The r and l coronary arteries drain deoxygenated blood into the right atrium on the posterior surface of the heart
  43. Electrocardiogram (ECG)
    • Technique that measure the electrical potentiol changes that occur in the heart during the cardiac cycle
    • Monitored by electrodes on the skin
    • Electrocardiograph
    • Leads detect differences in electrical potential between two points
  44. Heart Murmurs
    abnormal sound consiting of a clicking, rushing, or gurgling sound heard before, between, or after normal heart beat