- ATP binds to Myosin head. It causes the Myosin to release Actin. ATP hydrolyzes into ADP + Phosphate + Energy.
- ATP – ADP + Phosphate + Energy
- It cocks the Myosin enzyme (protein ) to high energy conformation(shape)
- Now the Phosphate released from Myosin. This releases a spring
- It pushes on the actin
- Now ADP is released
Chemical Energy -> Mechanical Energy
ATP is the energy currency of biological
Tropomyosin, Troponin
- Without calcium, the tropomyosin is blocking the ability of the myocin to attach or slide up the Actin so ite can keep pushing on it
- If the calcium concentration is high enough, they will bond to the troponin, which essentially nails down the tropomyosin that’s wound around the actin and when they change their conformation with the calcium ions, it moves the tropmyosin out of the way so the myocin can do what it does.
If we have a high calcium concentration within the cell the muscle will contractIt we have a low calcium concentration again, then all of a sudden these will release .They will be blocked and then the muscle will relax again.
Role of the sarcoplasmic reticulum in muscle cells