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Experiment Results Predict Question: Predict Question 1: When you increase the frequency of the stimulation, what do you think will happen to the amplitude (height) of the ventricular systole wave? Your answer : a. The amplitude will increase. Predict Question 2: If you deliver multiple stimuli (20 stimuli per second) to the heart, what do you think will happen? Your answer : a. wave summation 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) in the field below and then click Submit Data to record your answer in the lab report. You answered: 62 beats/min Which of the following statements about the contractile activity is true? You did not answer this question. Correct answer: a. The smaller waves represent the contraction of the atria. During which portion of the cardiac muscle contraction is it possible to induce an extrasystole? You correctly answered: d. during relaxation Experiment Data:
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Post-lab Quiz Results You scored 75% by answering 3 out of 4 questions correctly. 1. The amplitude of the ventricular systole did not change with the more frequent stimulation because You correctly answered: a. a new contraction could not begin until the relaxation phase 2. Which of the following do you think contribute to the inability of cardiac muscle to be tetanized? You correctly answered: a. the long refractory period of the cardiac action potential 3. Given the function of the heart, why is it important that cardiac muscle cannot reach tetanus? You correctly answered: b. The ventricles must contract and relax fully with each beat to pump blood. 4. An extrasystole corresponds to Your answer: b. an