The length of cardiac muscle in a resting individual is not at its optimal length for contraction. Greater cardiac muscle length, such as occurs with greater ventricular filling, will result in additional stretching of the cardiac muscle, increasing the muscle length and increasing the force of contraction.
1. Press the Start button and observe the recording. Allow to record for 10 seconds.
2. With the dropdown box set at 9mm, click the Change length button and observe your recording. What happens to the force of contraction? Why does this happen?
3. Use the cursor to measure the initial force of contraction and the change in force following the increase in muscle length. Put these values into the table underneath the trace.
View the video below before commencing this simulation.
In this experiment the initial muscle length is 8mm. Clicking the Change length button will increase the length to 9mm.
The recording time is 600 seconds.
Time (s)
Complete the below table based on data from the above simulation.
Make sure you collect data from a point after the contractions have stabilised
Selected value: (0, 0).
Enable plot values