Muscle Contraction

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…