HELP wtih ATP!!!!

[mtonell5]

A couple questions here..hopefully someone can help me. Im really stuck. I know that muscle cells in the biceps contain many mitochondria which are responsible for cellular respiration. And that in that process ATP and carbon dioxide are produced. So how is this ATP used by a muscle cell to effect contraction and then how is the carbon dioxide removed from the cell???
hope someone can help me
thaanks

[mith]

http://www.biology-online.org/9/10_muscle.htm

long story short, it causes a shape change

[MrMistery]

Myosin changes it's shape when it binds to ATP, making it able to detach from actin and move forward => sarcomeres shorten => contraction

[canan5000]

The diffusion of small molecules across phospholipid bilayers is possible because CO2 is a small non-polar molecule, and does not need to coupled with any kind of transport protein to leave the cell it can do it on its own accord. This is the mechanism that is used by respiring tissues such as contracting muscle.