Lect 33.begining of Heart

Question 1

Why is it beneficial to have longer contractions in cardiac muscles compared to skeletal muscles?
a. Ensures that the heart
chambers will relax and
refill with blood before
the next contraction
b. Increases the number
of contractions per
minute
c. Prevents the heart
chambers from refilling
with blood before the
next contraction

Answer 1

a. Ensures that the heart
chambers will relax
and refill with blood
before the next
contraction

Question 2

what is an Electrocardiogram

Answer 2

records electrical signal from heart to check for different heart conditions

Question 3

how does an EKG begin

Answer 3

atrial
depolarization. Atrial
contraction starts during
the latter part of the P
wave and continues during
the P-R segment

Question 4

what is the QRS complex

Answer 4

the Q R A waves representing depolarization of ventircles

Question 5

what occurs in the st segment

Answer 5

ventricles contract

Question 6

what occurs in the T wave

Answer 6

ventricle are repolarizing which is followed by ventricular relaxation

Question 7

what is the p wave

Answer 7

atrial depolarization

Question 8

what is the pr segment

Answer 8

atria contraction, conduction through av node/bundle

Question 9

hos to calculate an ekg ?

Answer 9

300/ # of boxes

Question 10

what is arrhythmia

Answer 10

irregular heart rhythm

Question 11

Which part of the graph would
most likely be affected if the AV
node pacemaker
cells did not fire an
action potential?
a. P wave
b. QRS complex
c. T wave
d. All of the above

Answer 11

b. QRS complex
c. T wave

Question 12

Which part of the
graph is most likely to be
affected during atrial
fibrillation?
a. P wave
b. QRS complex
c. T wave
d. All of the above
equally likely to be
affected

Answer 12

a. P wave

Question 13

ventricular fibrillation will result in
A. Low blood pressure
B. High blood pressure
C. No change in blood pressure
D. Fluctuating blood pressure

Answer 13

A. Low blood pressure