- 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.
What is the role of calcium in the cross bridge cycle? Calcium binds to troponin, altering its shape. What role does tropomyosin play in the cross bridge cycle? The displacement of tropomyosin exposes the active sites of actin, allowing cross bridges to form. How does troponin facilitate cross bridge formation?