PhysioEx 7.0 Skeletal Muscle - Activities 2 & 3 help???

Activity 2: Determining the Latent Period (p. 18)

4. The latent period should be approximately 2.78 msec.

The muscle cell is biochemically preparing for contraction, including events such as the
release of calcium from the sarcoplasmic reticulum, and the movement of the chemicals
of contraction within the cell; includes all biochemical events beginning with acetyl-
choline binding to the sarcolemma through the beginning of cross-bridge binding.

Activity 3: Investigating Graded Muscle Response to Increased Stimulus Intensity (p. 20)

7. The minimal stimulus is about 0.8 volts.

The maximal stimulus can be estimated at approximately 8.0 volts. However, if you
look carefully at the force measurements recorded in the data grid, you will see that
force increases until 8.2 volts is achieved.

As more voltage is delivered to the whole muscle, more muscle fibers are activated and
total force produced by muscle is increased.

Activity 2
How long is the latent period? 
2.78msec

What occurs in the muscle during this apparent lack of activity?   
The muscle cell is preparing for contraction.


Activity 3
What is the minimal, or threshold, stimulus? __________ V
0.8V

What is the maximal stimulus? __________ V
8.0V

How can you explain the increase in force that you observe?
There are more muscle fibers that are activated when there is more voltage delivered. This is turn causes the total force produced by the muscle to increase.

Awesome.

Thank you!