BIO 251: EXAM 3 ACTUAL COMPLETE REAL EXAM QUESTIONS AND CORRECT DETAILED ANSWERS (VERIFIED ANSWERS ) ALREADY GRADED A+.

BIO 251: EXAM 3 ACTUAL COMPLETE REAL EXAM QUESTIONS
AND CORRECT DETAILED ANSWERS (VERIFIED ANSWERS )
ALREADY GRADED A+.




The depolarization of the action potential in the pacemaker cells
is driven by the rapid influx of ________ ions through ________
channels.
A) sodium : funny

B) potassium : T-type calcium

C) potassium : funny

D) calcium : L-type calcium

E) sodium : T-type calcium - ANSWER-D



The period of ventricular contraction is called ________, whereas
the period of ventricular relaxation is called ________.
A) diastole : systole

B) action potential : refractory period

C) systole : diastole

D) V fib : A fib

E) action potential : graded potential - ANSWER-C



The P wave of the electrocardiogram is
created by A) ventricular depolarization.
B) atrial depolarization.

,C) ventricular repolarization.

D) atrial repolarization.

E) atrial hyperpolarization. - ANSWER-B



The repolarization of the ventricle is reflected in the
________ of the electrocardiogram. A) T wave
B) P-Q interval

C) P wave

D) R-R interval

E) QRS complex - ANSWER-A



The volume of blood that is pumped by the heart every minute
is determined by the equation A) EF = EDV - ESV.
B) CO = HR SV.

C) BP - PR VL.

D) T = PR/2.

E) SV = EDV - ESV. - ANSWER-B



What is the equation relating stroke volume (SV), end-diastolic
volume (EDV), and end-stroke volume (ESV)?
A) SV = EDV - ESV

B) SV = EDV ESV

C) SV = EDV + ESV/3

D) SV = EDV + ESV

E) SV = EDV/ESV - ANSWER-A

, Which of the following describes the effect of end- diastolic
volume on stroke volume?
A) An increase in end-diastolic volume stretches ventricular
muscle cells to lengths greater than optimum, decreasing the
strength of contraction and thereby decreasing stroke volume.
B) An increase in end-diastolic volume stretches ventricular
muscle cells to lengths closer to optimum, increasing the
strength of contraction and thereby increasing stroke volume.
C) A decrease in end- diastolic volume creates a vacuum
drawing more blood into the ventricle increasing stroke volume.
D) A decrease in end- diastolic volume allows ventricular
muscle cells to relax more during diastole, allowing more blood
to return to the heart increasing stroke volume.
E) A decrease in end- diastolic volume allows cardiac muscle
to relax, conserving energy for the next contraction, thereby
increasing stroke volume of that next contraction. - ANSWER-B


Which component of an ECG represents ventricular diastole?
A) T wave

B) QRS complex

C) Q-T interval

D) P-R interval

E) T-Q segment - ANSWER-E