What are the steps in the sliding filament theory of muscle contraction?
Answers
During muscle contraction the thin actin filaments slide over the thick myosin filament. When Calcium is present the blocked active site of the actin clears. Step B: Power stroke: myosin head pivots pulling the actin filament toward the center. Step C: The cross bridge detaches when a new ATP binds with the myosin.
The sliding filament theory of muscle contraction explain the working of muscle contraction of humans. The steps involved are:
● Ca++ ions are released in the terminal axon when nerve impulse is carried along the motor neurone from the brain and spinal cord to the muscle fibre.
● the increase in calcium Ion concentration stimulate the release of acetylcholine in synaptic cleft.
● this neurotransmitter released generate action potential across the muscle fibre for the contraction of muscles by binding on the receptor on sarcolemma.
● the action potential move to adjacent fibres transverse tubules
● the action potential in transverse tubules releases calcium ions from the sarcoplasmic reticulum, which stimulate muscle contraction.