KIN 252 Vagus Nerve PhysioEx PDF

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PhysioEx assignment that looked at the vagus nerve...

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PhysioEx Exercise 6 Activity 2

https://media.pearsoncmg.com/bc/bc_0media_ap/physioex/10/ex6/act2

PhysioEx Lab Report Exercise 6: Cardiovascular Physiology Activity 2: Examining the Effect of Vagus Nerve Stimulation Name: Jack Denton Date: 24 September 2020 Session ID: session-468a7069-edde-df3c-27b1-6d9ae173e4b9

Pre-lab Quiz Results You scored 100% by answering 4 out of 4 questions correctly. 1 The effect of the parasympathetic nervous system on the heart is to You correctly answered: decrease the heart rate. 2 The branch of the autonomic nervous system that dominates during exercise is You correctly answered: the sympathetic branch. 3 Parasympathetic stimulation reaches the heart through You correctly answered: vagus nerves, which are cranial nerves. 4 The usual pacemaker of the heart You correctly answered: is the sinoatrial node.

Experiment Results Predict Question 1 Predict Question: What do you think will happen if you apply multiple stimuli to the heart by indirectly stimulating the vagus nerve? Your answer: The heart rate will decrease and the heart will stop. Stop & Think Questions 1 Watch the contractile activity from the frog heart on the oscilloscope. Enter the number of ventricular contractions per minute (from the heart rate display). i

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PhysioEx Exercise 6 Activity 2

https://media.pearsoncmg.com/bc/bc_0media_ap/physioex/10/ex6/act2

You answered: 62 beats/min. 2 The vagus nerve carries You correctly answered: signals that decrease the heart rate. 3 Enter the number of ventricular contractions per minute (from the heart rate display). You answered: 62 beats/min. 4 The response that resumed the heartbeat after the vagus nerve stimulation is called You correctly answered: vagal escape. Experiment Data

Post-lab Quiz Results You scored 100% by answering 4 out of 4 questions correctly. 1 Extreme vagus nerve stimulation affects the heart by You correctly answered: stopping the heart completely. 2 Vagal escape probably involves You correctly answered: sympathetic reflexes. 3 Research shows that, in the absence of neural and hormonal influences, the SA node generates action potentials at a frequency of approximately 100 times per minute. However, the resting heart rate is approximately 70 beats per minute, which suggests that i

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PhysioEx Exercise 6 Activity 2

https://media.pearsoncmg.com/bc/bc_0media_ap/physioex/10/ex6/act2

You correctly answered: the parasympathetic nervous system has more control over heart rate. 4 The SA (sinoatrial) node in the human heart is located You correctly answered: in the right atrium.

Review Sheet Results 1 Explain the effect that extreme vagus nerve stimulation had on the heart. How well did the results compare with your prediction? Your answer: The extreme vagus nerve stimulation caused the heart to slowly decrease the heart rate which eventually stopped. My prediction was correct because as the stimulation occurred the heart rate decreased and then went into a flat line indicating the heart stopped. 2 Explain two ways that the heart can overcome excessive vagal stimulation. Your answer: Two ways that the heart can overcome excessive vagal stimulation is sympathetic reflexes and the initiation of a rhythm by the Purkinje Fibers. 3 Describe how the sympathetic and parasympathetic nervous systems work together to regulate heart rate. Your answer: The sympathetic nervous system increases the heart rate and the parasympathetic nervous system decreases the heart rate. 4 What do you think would happen to the heart rate if the vagus nerve was cut? Your answer: If the vagus nerve was cut the heart rate would increase.

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