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Without muscles, we wouldn't be able to do much of anything. This tutorial begins to explore what muscle cells are and how they contract in order to move our bodies (or do things like breath and pump blood).
How myosin and actin interact to produce mechanical force.
Tropomyosin and troponin and their role in regulating muscle contraction. How calcium ion concentration dictates whether a muscle is contracting or not.
The role of the sarcoplasmic reticulum in controlling calcium ion concentrations within the muscle cell.
Understanding the structure of a muscle fiber