The Cardiovascular System

1. Describe the events of an action potential in cardiac muscle, and explain the importance of calcium ions to the contractile process. 

2. Discuss the difference between nodal cells and conducting cells, and describe the components and functions of the conducting system of the heart. 

3. Identify the electrical events associated with a normal electrocardiogram. 

4. Explain the events of the cardiac cycle, including atrial and ventricular systole and diastole, and relate heart sounds to specific events in this cycle. 
 

Part A  Cardiac Action Potentials 

1. Compare and contrast a cardiac action potential with a skeletal muscle action potential.  

2. Describe 3 similarities 

3. Describe 3 differences 
 
 

Skeletal Action Potential	Cardiac Action Potential
1.	1.
2.	2.
3.	3.

  

  A written response using the table above and submitted to the instructor. 

Part B  Questions 

1. Explain the physiological purpose of the plateau phase in the cardiac action potential. 

2. Why is it important for impulses from the atria to be delayed at the AV node before they pass into the ventricles? 

  
  A written response to the two questions submitted to the instructor. 
 

Part C  Measurement of the EKG 

1. Work in pairs. 

2. Conduct EKG measurements on your partner following the instructions provided by the professor.  

3. At the end of the activity you should have performed a resting and active EKG measurements on both members and recorded the information described in the lab activity handout.  
 

   Submit your written report to the instructor.