Where are pacemaker cells located? Why are they called pacemaker cells? Be able
ID: 3517070 • Letter: W
Question
Where are pacemaker cells located? Why are they called pacemaker cells? Be able to interpret the graph of pacemaker action potentials of cardiac pacemaker cells. The movement of what ions causes slow depolarization, until threshold is reached? What ion channels open at threshold? What causes repolarization? What is the intrinsic rate of the pacemaker cells? During resting, what neurons help control these cells? How does this neuronal control affect the rate of the pacemaker cells?
Will give thumbs up if all questions answered!
Explanation / Answer
1. Where are pacemaker cells located?
Answer- the pacemaker cells - the sinoatrial node also known as the SA node is located in the right atrium.
2. Why are they called pacemaker cells?
Answer- they are called pacemaker cells because they are primarily responsible for the heart's electrical activity.
3. The movement of what ions causes slow depolarization, until threshold is reached?
Answer- the slow influx of sodium ions causes slow depolarization until threshold is reached.
4. What ion channels open at threshold?
Answer- voltage-gated sodium ion channels open at threshold.
5. What causes repolarization?
Answer- potassium leaving the cell through voltage-gated potassium channels causes repolarization.
6. What is the intrinsic rate of the pacemaker cells?
Answer- 60 to 100 beats per minute (bpm).
7. During resting, what neurons help control these cells?
Answer- parasympathetic nerves ( particularly vagus nerve) and sympathetic nerves ( T1-T4)
8. How does this neuronal control affect the rate of the pacemaker cells?
Answer- parasympathetic nerves ( particularly vagus nerve) - decreases the rate of action potential production and therefore decreases the heart rate. sympathetic nerves ( T1-T4)- increases the rate of action potential production and therefore increases the heart rate.
Related Questions
drjack9650@gmail.com
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.