Heart & ECG Lab
What is the correct order the flow of blood entering the heart from the systemic circulation through the venae cava?
1. right atrium 2. right ventricle 3. pulmonary trunk 4. pulmonary veins 5. left atrium 6. left ventricle
How many chambers does the heart consist of?
4
Which ECG component corresponds to the depolarization of the atria?
P wave
The time from ventricular depolarization to the end of ventricular repolarization corresponds to which ECG component?
Q-T interval
The electrical signal on an ECG that represents atrial repolarization is masked by which of the following components:
QRS complex
The first heart sound, "lubb" is heard when the AV valves close, and this is related to the _________ on an ECG
QRS complex
When ECG component reflects depolarization of the ventricles?
QRS complex
In an ECG, the _____ wave is associated with ventricular repolarization
T
Which ECG component corresponds to the repolarization of the ventricular fibers?
T wave
True or False: the QRS complex on an ECG reflects ventricular depolarizaton
True
The _______ ______ can be determined by counting the number of QRS complexes on the ECG during one minute
cardiac rate
True or False: they sympathetic nervous system increases heart rate while the parasympathetic nervous system decreases heart rate
True
The AV valves are closing during ventricular __________
contraction (systole)
The ________ is a straight line used as a point of departure for the electrical activity recorded in an ECG
baseline
Leads that measure the potential differences between two electrodes (a positive and a negative) are called ______ leads
bipolar
How are the sounds of a heartbeat created?
by heart valves closing
________ is the phase of the cardiac cycle when the heart is relaxing
diastole
At which point on an ECG is the first heard sound, "lubb", heard?
during the QRS complex
_________ impulses stimulate cardiac muscle to contract
electrical
What does an ECG measure?
electrical impulses
The electrical activity that occurs in the heart when it contracts and relaxes can be recorded, and is called a(n) _________
electrocardiogram
The second heart sound "dupp" is heard when the semilunar valves close, and this is related to the ________ on an ECG
end of the T wave
Blood leaves the ventricles during which period?
from the end of the first heart sound to the beginning of the second heart sound
The mitral (or bicuspid) atrioventricular valve controls the flow between the:
left atrium and ventricle
Which ventricle pumps blood through the aorta to the body?
left ventricle
A turbulent noise, created by the back flow of blood as a heart valve closes is called a _________
murmur
Which of the following correctly describes the electrode placements in the Einthioven's triangle arrangement?
one on each wrist and one on the left side
An interval of an ECG is:
one or more waves and a straight line
The semilunar valves are closing during ventricular _________
relaxation (diastole)
After contracting, the heart relaxes. This happens because of an electrical change called ___________
repolarization
Which valves are located between the exits of the ventricles and the two large arteries?
semilunar valves
What is happening in the heart during the second heart sound ("dupp")?
semilunar valves are closing
The P-Q interval of an ECG corresponds to the time for a cardiac impulse to travel from:
the SA node through the node
To record an ECG, electrodes are placed on the test subject. A lead is:
the arrangement of electrodes with respect to each other
The P-Q (or P-R) interval is the time it takes for:
the electrical impulse to spread through the atria
At which point on an ECG is the second heart sound, "dupp", heard?
the end of the T wave
Which heart sound is shorter and crisper?
the first heart sound
On an ECG, the P wave has a smaller amplitude than the QRS complex. Why is this?
the muscle mass of the atria is smaller than the muscle mass of the ventricles
The ventricles relax during:
the second heart sound
Which heart chamber have the thickest walls?
the ventricles
The atria pump blood into the ventricles, while the ventricles pump blood around the entire body. How is the difference in function reflected in the structure of the heart?
the ventricles are thicker than the atria an dthe ventricles are larger than the atria
What is the function of the four heart valves?
they allow the blood to flow in only one direction through the heart
A cardiac cycle covers the events that occur from the beginning of one heart beat to the beginning of the next
true
The S-T segment of an ECG is the time for:
ventricles to contract
In an ECG, the _____ wave is associated with atrial depolarization
P
True or False: you cannot record an ECG on a person who has a heart condition
False
The following information can be determined from an ECG:
HR and heart rhythm
A segment of an ECG is:
a straight line between two waves
The vertical valves on the ECG are a measure of:
amplitude
The electrical impulse is delayed in the AV node before propagating to the bundle of His. During this delay the _________ contract
atria
The first heart sound, "lubb", is associated with the closing of which valves?
atrioventricular (AV) valves
Which valves are located between the atria and the ventricles?
atrioventricular (AV) valves
