Cardiac Muscle Contraction Quiz

Please wait while the activity loads.
If this activity does not load, try refreshing your browser. Also, this page requires javascript. Please visit using a browser with javascript enabled.

If loading fails, click here to try again

This quiz covers topics on cardiac muscle contraction. Have fun and enjoy!

Start

Congratulations - you have completed Cardiac Muscle Contraction Quiz. You scored %%SCORE%% out of %%TOTAL%%. Your performance has been rated as %%RATING%%

Your answers are highlighted below.

Question 1

What is the end systolic volume?

	The amount of blood left in the ventricle right after ventricular contraction.
	The amount of blood in the ventricle before ventricular contraction. Hint: This is actually the end diastolic volume. Come on, try again, I know you’ll get it this time.
	The amount of blood in the atrium right before atrial contraction. Hint: Nope. You have to try again... I know you’ll get it this time.
	The amount of blood left in the atrium right after atrial contraction. Hint: I think you got it all mixed up. Change a few parts and you’ll get the answer :)

Question 1 Explanation:

Wow, you’re doing good at this! When the ventricles contract, and it pushes the blood out to the lungs and out to the rest of the body, the amount of blood we have left is the end systolic volume. If you want to go back and review this concept, you can watch this video.

Question 2

If the end diastolic volume is 110 mL and end systolic volume is 40 mL, what is the stroke volume?

	70 mL
	150 mL Hint: This one is too much.
	100 mL Hint: How did you get this? Come on, I know you can get it.
	40 mL Hint: This one’s exactly the same as the end systolic volume which wouldn’t make sense. Try again, I know you’ll pick the right one.

Question 2 Explanation:

Perfect! Stroke Volume is the difference between the end diastolic volume and end systolic volume. This is explained more in this video.

Question 3

What does the Frank-Starling mechanism of the heart generally tells us?

	Stroke volume is increased because of an increase in the filling of blood in the heart.
	Stroke volume is increased because of increased oxygen in the blood. Hint: It’s not the oxygen that’s increased. I know you’ll pick the right one this time.
	Stroke volume is increased because of increased end systolic volume. Hint: In fact, systolic volume is not increased at this point. Think of something else that increases during this time.
	Stroke volume is decreased because of a decrease in the end systolic volume. Hint: I think you got it all mixed up. Come on, think harder. I know you’ll get it.

Question 3 Explanation:

That’s right! This is one way of regulating stroke volume. If the heart gets filled with more blood, that is naturally going to cause a stronger contraction sending more blood out of the heart and increasing the stroke volume even further by decreasing the end systolic volume. More of this topic is clearly explained in this video.

Question 4

What happens during an isovolumetric contraction?

	The ventricles contract but the semilunar valves do not open to allow blood to be ejected to the lungs.
	The blood volume in the atrium remains the same during contraction. Hint: You’re just a little bit confused. I do know you’ll get it this time :)
	The blood volume remains the same because the bicuspid valve remains closed. Hint: It’s not the bicuspid valve that doesn’t allow the blood to be ejected to the lungs. Hmm, that should give you a clue :)
	The stroke volume remains the same as the atrium contracts. Hint: Yes, the volume remains the same but, we are not concerned about the atrial contraction here. I guess, you know this by now. :)

Question 4 Explanation:

You’re really good! During an isovolumetric contraction, the blood volume stays the same in the ventricle as the ventricle contracts because the semilunar valves do not open. This happens upto a point where the valves open and ejects the blood. More of this is explained in this http://www.interactive-biology.com/2368/051-isovolumetric-contraction/v.

Question 5

What does this “T wave” of the ECG/EKG represents?

	repolarization of the ventricles
	depolarization of the atria Hint: I think you got confused right there. This is represented by the P wave. Come on, try again. I know you’re good at this.
	depolarization of the ventricles Hint: Nope, try the opposite of this process. This is represented by the QRS wave. I know you’ll get it.
	repolarization of the Purkinje fibers Hint: No, that’s not enough to cause such a wave. Try another one.

Question 5 Explanation:

Good job! If you want to review more on repolarization and depolarization, you can go back and watch Episodes 009, 010, 045, and 047 for a better understanding of muscle contraction specifically cardiac muscle contraction.

Question 6

The sinoatrial node has significantly strong conductance for which of the following ions?

	sodium ions
	potassium ions Hint: No, but this exists with this other ion only in a smaller number.
	zinc ions Hint: No, try again. It has an charge of +1.
	magnesium ions Hint: Come on try again, I know you know the answer.

Question 6 Explanation:

Because the cell is much more permeable to sodium, more sodium will be coming in than potassium leaving. Because there will be more positives going in than leaving, a pacemaker potential is achieved where the cell normally depolarizes. This is discussed more in this video.

Question 7

How does a skeletal muscle pump help in increasing the stroke volume in the heart?

	By increasing the end diastolic volume causing more blood to be sent back to the heart or an increase in venous return.
	By increasing end systolic volume. Hint: It’s not the end systolic volume that’s increased, that would decrease the stroke volume. Think again. I know you’ll get it this time.
	By increasing end diastolic blood by increasing the amount of time for the ventricles to be filled. Hint: It’s not because of the length of time that we are increasing the end diastolic blood with a skeletal muscle pump. Try another answer. I think you know what it is by now.
	By decreasing venous return to the heart. Hint: No, but quite the opposite happens.

Question 7 Explanation:

Skeletal muscles contracts in a way that helps to push the blood in the direction that it needs to go, helping to push that blood so the blood can go faster and more blood can go to the heart. This is explained more in this video.

Question 8

Which wave in an ECG/EKG represents the depolarization of the ventricles?

	QRS wave
	P wave Hint: This represents the depolarization of atria.
	T wave Hint: This represents the repolarization of ventricles.
	U wave Hint: This doesn’t normally appear in an EKG. Sometimes, they are said to represent repolarization of the Purkinje fibers.

Question 8 Explanation:

You can see more on how to read an EKG in this video.

Question 9

Which test records the electrical activity of the heart?

	electrocardiogram
	cardiogram Hint: It’s missing something. Take note, “electrical activity.”
	electrical cardioigraphy Hint: Please, try something else.
	electropump Hint: Give it another try. I know you can do this.

Question 9 Explanation:

Good job! You can watch Episode 048, e to learn more about ECG and how they are read, "How to Read an Electrocardiogram (ECG/EKG)."

Question 10

What do you call the amount of blood that is pumped by one ventricle during each heart beat?

	Stroke volume
	end systolic volume Hint: This is the amount of blood left in the ventricle RIGHT AFTER the ventricular contraction.
	end diastolic volume Hint: This is the amount of blood in the ventricle RIGHT BEFORE ventricular contraction.
	systo-diastolic volume Hint: I don’t think there is such thing. Come one, try again. I know you’ll get it this time :)

Question 10 Explanation:

Right! Stroke volume is derived by subtracting the end systolic volume from the end diastolic volume. You can learn more about this in this video.

Once you are finished, click the button below. Any items you have not completed will be marked incorrect. Get Results

There are 10 questions to complete.

List

Return

Shaded items are complete.

1	2	3	4	5
6	7	8	9	10
End

Return

Cardiac Muscle Contraction Quiz

Cardiac Muscle Contraction Quiz

Image Sources

Support Interactive Biology

What People are Saying