Exercise 6: Cardiovascular Physiology: Activity 5: Examining the Effects of Various Ions on Heart Rate Lab Report Exercise 6: Cardiovascular Physiology: Activity 5: Examining the Effects of Various Ions on Heart Rate Lab Report Pre-lab Quiz Results
Pre-lab Quiz Results
You scored 100% by answering 4 out of 4 questions correctly. You scored 100% by answering 4 out of 4 questions correctly. 1.
1. Which organelle Which organelle in the in the cardiac muscle cardiac muscle cell stores cell stores calcium?calcium? You correctly answered: b. sarcoplasmic reticulum
You correctly answered: b. sarcoplasmic reticulum 2.
2. Verapamil is a Verapamil is a calcium-channel blocker. calcium-channel blocker. Its effectIts effects could be s could be described asdescribed as You correctly answered: d. negative chronotropic and
You correctly answered: d. negative chronotropic and negative inotropic.negative inotropic. 3.
3. When the cardiac When the cardiac muscle cell is at muscle cell is at rest, where is rest, where is most of the most of the potassium found?potassium found? You correctly answered: c. in the
You correctly answered: c. in the cytosolcytosol 4.
4. Resting cardiac Resting cardiac muscle muscle cells are cells are most most permeable topermeable to You correctly answered: b. potassium.
You correctly answered: b. potassium.
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07/31/13 07/31/13 page page 22 Experiment Results Experiment Results Predict Question: Predict Question: Predict Question 1:
Predict Question 1: Because calcium-channel blockers are negative chrBecause calcium-channel blockers are negative chronotropic and negative inotropic, what efonotropic and negative inotropic, what effect do youfect do you think increasing the concentration of calcium will have on heart rate?
think increasing the concentration of calcium will have on heart rate? Your answer : a. positive
Your answer : a. positive chronotropic, positive inotropicchronotropic, positive inotropic Predict Question 2:
Predict Question 2: Excess potassium outside of the Excess potassium outside of the cardiac cell decreases the resting potentcardiac cell decreases the resting potential of the plasma membrane,ial of the plasma membrane, thus decreasing the force of contraction. What effect (if any)
thus decreasing the force of contraction. What effect (if any) do you think it wildo you think it willl initially initially have on heart rate?have on heart rate? Your answer : b. decrease heart rate
Your answer : b. decrease heart rate Stop & Think Questions:
Stop & Think Questions:
Where in the cardiac muscle cell is most of the sodium normally found? Where in the cardiac muscle cell is most of the sodium normally found? You correctly answered: a. outside of the
You correctly answered: a. outside of the cellcell Experiment Data:
Experiment Data:
S
Soolluuttiioonn HHeeaarrttRRaattee
--- 6622
C
Caallcciiuumm 7722
Sodium
Sodium 34 34 then then erraticerratic
P
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07/31/13 page page 44 Post-lab Quiz Results
Post-lab Quiz Results
You scored 100% by answering 4 out of 4 questions correctly. You scored 100% by answering 4 out of 4 questions correctly. 1.
1. The addition The addition of most of most of the of the ions resulted ions resulted inin You correctly answered: c. an erratic heart rate. You correctly answered: c. an erratic heart rate. 2.
2. The effecThe effect of t of potassium on potassium on the heart the heart isis
You correctly answered: b. negative chronotropic, negative inotropic. You correctly answered: b. negative chronotropic, negative inotropic. 3.
3. The ion that The ion that had the had the most pronounced most pronounced effect on effect on heart rate heart rate waswas You correctly answered: c. potassium.
You correctly answered: c. potassium. 4.
4. Ectopic pacemakers can Ectopic pacemakers can be caused by excessive be caused by excessive leakage of potassium leakage of potassium into cardiac cells, rinto cardiac cells, resulting in pacemakersesulting in pacemakers appearing in abnormal locations in the heart muscle. This
appearing in abnormal locations in the heart muscle. This hyperkalemia hyperkalemia (excess potassium) decreases the resting potential(excess potassium) decreases the resting potential of the cardiac muscle cell.
of the cardiac muscle cell. What effect do you think this would What effect do you think this would have on the force of contraction?have on the force of contraction? You correctly answered: d. decrease, negative inotropic
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07/31/13 page page 55 Review Sheet Results
Review Sheet Results 1.
1. Describe the effect Describe the effect that increasing the that increasing the calcium ions had on calcium ions had on the heart in tthe heart in this activity. How well his activity. How well did the results did the results comparecompare with your prediction?
with your prediction? Your answer:
Your answer:
As my prediction and results show,
As my prediction and results show, Increasing the calcium ions made the Increasing the calcium ions made the blood pressure and heart rates to be blood pressure and heart rates to be irregular.irregular. This blocks movement of calcium through channels
This blocks movement of calcium through channels and throughout phases of cardiac action potentials.and throughout phases of cardiac action potentials. 2.
2. Describe the effect that incrDescribe the effect that increasing the potassium ions initially had on the heareasing the potassium ions initially had on the heart in this activity. Relate this to t in this activity. Relate this to the restingthe resting membrane potential of the cardiac muscle cell. How well did the results compare with your prediction?
membrane potential of the cardiac muscle cell. How well did the results compare with your prediction? Your answer:
Your answer: As shown in the
As shown in the results, excessive potassium ions decreases the resting potential results, excessive potassium ions decreases the resting potential of the plasma membrane and decreasesof the plasma membrane and decreases the force of contraction. My prediction was correct.
the force of contraction. My prediction was correct. 3.
3. Describe how calcium Describe how calcium channel blockers archannel blockers are used te used to treat o treat patients and patients and why?why? Your answer:
Your answer:
Calcium channel blockers are used
Calcium channel blockers are used to treat high blood pressure and to treat high blood pressure and abnormal heart rates. This blocks movement of calciumabnormal heart rates. This blocks movement of calcium through channels and throughout phases of cardiac
