Originally Posted by Zackk

- Excitation
-Ca+ stimulates Acetylcholine release from the nerve cell
-ACh binds to receptors on muscle cell
-Na+ enters and causes Action Potential to spread across the muscle cell

- Excitation and Contraction
-Action Potential opens up Ca+ channels
-Ca+ enters cytosol and binds with troponin
-Troponin-Tropomyosin complex exposes active sites on Actin

- Contraction
-Myosin heads bind with active sites on actin
-Power stroke occurs (Shortening of Sarcomere)

- Relaxation
-ACh is reabsorbed
-Ca+ is pumped back into Sarcoplasmic Reticulum by active transport
-Tropomyosin reblocks active site on Actin
-Muscle returns to resting length

Rinse and Repeat.

ITT han helps me study for said exam, and we all learn the neurophysical action of a muscle contraction. :loco: