Physiology 3120 Lecture Notes - Lecture 11: Rigor Mortis, Calsequestrin, Rate-Determining Step

• School: Western University
• Department: Physiology
• Course: Physiology 3120
• Professor: Tom Stavraky

Document Summary

So even if each of them shortens a tiny bit, with all 100 000 sarcomeres shortening, the muscle cell shortens as well. Very long sarcomere with no overlap of thick and thin myofilaments thus cannot grab on to actin in thin myofilament thus no muscle contraction = 0% tension in muscle cell. As start overlap of thick and thin myofilaments, start to increase tension in muscle cell. The more the overlap, the higher the tension. In the human body, only steps 2-5 are possible ie: never gets to the extremes: ap in red is going down the t-tubule. Atpases can be saturated thus it cannot work as fast as the release channels at 20 molecules/sec/atpase. When carry heavy bags of groceries and then put down the bags, the arm still cannot relax. Because when you were carrying the bags, the muscle were contracting, aps were being fired, Ca++ was being released continuously until muscle cells were flooded with ca++