BIO 132 – Anatomy and Physiology II

LECTURE 15:  CARDIAC PHYSIOLOGY I

Study Outline

Answers

 

15.1.  Comparison of Cardiac and Skeletal Muscle:

a.       sarcomeres; action potentials; calcium

b.      pacemaker; gap junctions

c.       involuntary

d.      about 1 msec; several hundred msec

 

15.2.  Action Potential of a Cardiac Contractile Cell:

a.         –90 mV; K+; Na+

b.      voltage gated Na+ channels; ENa

c.       an increase in Ca2+ permeability; a decrease in K+ permeability; voltage gated Ca2+ channels.

d.      K+ permeability; Ca2+ permeability; Na+ permeability

e.       refractory; relax

 

15.3.  Action Potential of a Cardiac Conducting Cell:

a.       conducting cells; conduction system

b.      extrinsic nerves; hormones; auto-rhythmicity

c.       maximum diastolic potential

d.      a decrease in K+ permeability; threshold

e.       Ca2+

f.        K+ permeability; Ca2+ permeability

 

15.4.  The Conduction System:

a.       SA node; sinus rhythm

b.      superior vena cava; right atrium; connective tissue

c.       internodal path

d.      right atrium; interatrial septum

e.       AV delay

f.        Bundle of His; bundle branches; Purkinje cells

g.       muscular interventricular septum; papillary muscles; ventricular walls

h.       arrhythmias; fibrillation

i.         ectopic focus

 

15.5.  The EKG:

a.       extracellular electrical currents; electronegativity; electropositivity

b.      atrial depolarization; half

c.       ventricular depolarization; AV node; Bundle of His; bundle branches

d.      ventricular repolarization; QRS complex

e.       fully depolarized; plateau

f.        RR interval; tachycardia; bradycardia; 75 beats/min

g.       P waves; ventricular fibrillation

 

15.6.  Excitation-Contraction Coupling:

a.       Ca2+; Ca2+ release from the SR

b.      troponin C

c.       Ca2+ ATPase on the sarcolemma; Ca2+ ATPase on the SR; Ca2+ /Na+ exchanger on the sarcolemma

d.      increased force of contraction; epinephrine; cardiac glycosides; Na+/K+ pump; increase

e.       inotropic

 

15.7.  The Cardiac Cycle: 

a.       cardiac cycle

b.      isovolumetric relaxation; mitral; aortic semilunar valves; atrial pressure

c.       rapid ventricular filling; diastasis; diastole

d.      end diastolic volume

e.       mitral valve; first; isovolumetric contraction

f.        aortic semilunar valve; ventricular ejection

g.       T; aortic semilunar valve; second heart sound

h.       end systolic volume; stroke volume; end diastolic volume; end systolic volume