Muscle Contraction is Triggered by an Influx of Calcium Ions:
- Action-potential from a motor neurone stimulates a muscle cell.
- Depolarisation of the sacrolema occurs.
- This depolarisation spreads down the T-tubules to the sacroplasmic reticulum.
- Sacroplasmic reticulum releases stored Ca2+ into the sacroplasm.
- Ca2+ bind to the troponin, causing it to change shape.
- The attached tropomysin is pulled away from the actin-myosin binding site on the…