BIOD43H3 Lecture Notes - Lecture 1: Endoplasmic Reticulum, Swim Bladder, Maximum Force
Tutorial 1: Design and Function of Superfast Muscles: New insights into the Physiology of
Skeletal Muscle
• Participation, 10%
• Tutorial Assignments, 10%
• Oral Presentation, 20%
o Evaluation of peers included in this
1. Wh is a ight‐shifted foe/pCa curve thought to be supportive of faster
contraction/relaxation cycling in the toadfish singing muscle? (Note: look up what pCa means
if you've forgotten)
Figure 4:
In the x we have pCa, y axis is % Maximum Force. We have red, white and swimbladder muscle.
We have faster contraction and relaxation time for swimbladder compared to the other
muscles, since we have a steeper slope for swimbladder shifted to the right, which indicates
more Ca2+. The lower the pCa the higher the Ca2+. The threshold is lower. Faster time of
relaxation, Ca2+ pumping faster and direction is changing.
2. Why is it suggested that PARV does not play a role in sequestering AND THEN releasing (to
Ca++ ATPase pump activity, etc.) Ca++ with each contraction cycle?
There is active pumping of Ca2+ in sarcoplasmic reticulum, high in fast muscle.
Toadfish call for many hours, which may suggest PARV would become quickly
saturated, and hence ineffective at sequestering Ca2+. The pump is actively working.
Considerable Ca2+ can be left bound in the myoplasm at the point of relaxation and that this is
sequestered during the postrelaxation phase accompanied by hydrolysis of ATP.
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
Tutorial 1: design and function of superfast muscles: new insights into the physiology of. In the x we have pca, y axis is % maximum force. We have faster contraction and relaxation time for swimbladder compared to the other muscles, since we have a steeper slope for swimbladder shifted to the right, which indicates more ca2+. The lower the pca the higher the ca2+. Faster time of relaxation, ca2+ pumping faster and direction is changing: why is it suggested that parv does not play a role in sequestering and then releasing (to. There is active pumping of ca2+ in sarcoplasmic reticulum, high in fast muscle. Toadfish call for many hours, which may suggest parv would become quickly saturated, and hence ineffective at sequestering ca2+. Considerable ca2+ can be left bound in the myoplasm at the point of relaxation and that this is sequestered during the postrelaxation phase accompanied by hydrolysis of atp. Each of the spikes corresponds to one contraction/relaxation.
