The correct answer is option B, that is, the release of calcium ions makes actin and myosin to combine with each other.
At the time of the stimulation for a muscle contraction, calcium is discharged into the fiber. It combines with troponin and instigates it to move tropomyosin, exposing the binding site for the myosin cross-bridge. Thus, the face of the actin filament is now free to combine with myosin heads to initiate contraction of the muscle.
Answer: "water vapor" .
__________________________________________
DNA contains genetic information and is in chromosomes. This means that through DNA diseases can be passed on for example, cystic fibrosis. DNA identifies who a person is and no one has the same DNA as each other.
Because just the right amount of nitrogen and phosphorus makes the soil grow really good. But too much will kill the soil.
I'm pretty certain that the earth's circumference is greatest at the equator.