Muscle Exam

 

 

1. After a skeletal muscle fiber is treated with a membrane permeable drug that speeds up the action of the SR Ca+2-ATPase, how would the first twitch differ?

 

 

2. After a skeletal muscle fiber is treated with a membrane permeable drug that speeds up the action of the SR Ca+2-ATPase, how would contraction differ after multiple and frequent action potentials?

 

 

3. During muscle contraction, the portion of the sarcomere that shortens is:

 

 

4.Which of the following is the typical order of motor unit recruitment?

 

 

5. Which factor regulates cross-bridge formation in skeletal muscle?

 

 

6.Which of the following types of muscles have sufficient numbers of gap junctions between fibers to propagate action potentials between cells?

 

 

7. The dominant mechanism for the removal of Ca²⁺ from the cytosol following contraction of the cardiac muscle cell is the:

 

 

8.Smooth muscle cells differ from skeletal muscle cells in that smooth muscle does NOT contain:

 

9. In smooth muscle cells, a pacemaker potential differs from a graded potential because pacemaker potentials: