I've looked at several sources including my teacher and all of them seem to either contradict each other directly or give a rather hazy explanation in regards to the role of ATP in muscle contraction. From what I can gather from the official textbook, the following occurs:
One ATP molecule is used in each cycle.
ATP binds to the myosin head AFTER the cross bridge has been broken and only releases energy for the myosin head to resume its original position.
To me this doesn't really make sense because surely energy is needed to form the cross bridge in the first place and certainly to slide the actin across? It would be helpful if someone could clarify because all the textbooks I've looked at have failed to do so.
Thanks, hope this makes sense
AQA Bio5 - role of ATP in the cycle of actin-myosin crossbridge formation watch
- Thread Starter
- 14-05-2013 15:19
- 15-05-2013 19:15
think about a mouse trap.
You pay energy in to bend the spring back and 'set' the trap.
Later on the spring will be released and the trap moves. The energy for this movement comes from that stored earlier.