<span>Cross bridges are created when myosin heads bind to ATP. This phenomenon is basically muscle contraction at work. In order for myosin heads to be bound with ATP at the actin active site, it must be excited with Calcium.
Once myosin heads bind with ATP, it begins to slide and perform muscle contractions in the body, allowing a person to move.</span>
Answer:
the answer is 40c because i just took the test
Explanation:
I would say that it would be C, Relationships of trees to other organisms in the rain forest...
