Post-exercise 30 s Post-exercise 60 s Post-exercise 120 s Post-exercise Post Lab
ID: 3513646 • Letter: P
Question
Post-exercise 30 s Post-exercise 60 s Post-exercise 120 s Post-exercise Post Lab Questions 7. How is heart rate controlled by the nervous system? 8. What happened to the R-R interval and heart rate after exercise? 9. Immediately after exercise (Exercise 2), was the amplitude of the pulse smaller or larger than during the resting period? 10. Immediately after hand exercise (Exercise 3), was the amplitude of the pulse smaller 11. What happened to the blood volume pulse amplitude during recovery from hand or larger than during the resting period? exercise? Calculate cardiac output for an athlete with HR = 40 BPM and SV = 0.125 L. How would valvular stenosis (narrowing) of the atrioventricular valves affect ejection 12. 13. of blood from the heart? 14. Based on your understanding of heart and muscle function, why would it be necessary for a patient to be as still as possible while recording the ECG?Explanation / Answer
7. heart rate is controlled by the nervous system. the increase and decrease in the heart rate is controlled by the symphathetic and para synphathetic nervous systems. the medulla oblongata of the brain is connected with the two nerves with SA node of the heart.
symphathetic nervous system is responsible for the stimulation and release of neurotransmitter at the SA node to increase the heart rate. where as parasymphathetic nervous system releases neurotransmitters at SA node which decreases the heart rate. many symphathetic nerves are alos linked to the walls of the ventricles which involves in the increase the force of the ventricular contraction.