- Doctorate - 4-7 years, including doctoral dissertation. You can do a Phd. right from 4 year college without getting a masters first, but most people get the masters first. MD - Medical Doctor - Med school and internship, done after BS or BA degree - can take 8 years.
Because of the relationship between the dihydropyridine receptor and the ryanodine receptor, that causes calcium that is stored in the sarcoplasmic reticulum to be released, and the calcium released then causes muscle contraction.
Interactions of Skeletal Muscles in the Body. 1  Prime mover. The muscle that has the major responsibility for causing a particular movement is called the prime mover. 2  Antagonists. Muscles that oppose or reverse a movement are antagonists; when a prime mover is active, its antagonist is stretched and relaxed. 3  Synergists.