Chapter 8 : Muscle Contraction and Relaxation Flashcards
Contraction step 1.
Acetylcholine rushes into the neuromuscular junction
Contraction step 2.
Sarcolemma soaks up the Na+ (sodium ions)
Contraction step 3.
Na+ ions make the inside of the cell positively charged while the outside is negatively charged
Contraction step 4.
The difference in changes creates an action potential
Contraction step 5.
Equalization of the action potential sweeps across the sarcolemma and into the T-tubules like and wave
Contraction step 6.
This causes calcium ions (Ca+) to be released into the sarcoplasmic reticulum
Contraction step 7.
Calcium exposes binding sites on the Actin filaments
Relaxation step 1.
Acetylcholine is broken down by enzymes in the sarcolemma
Relaxation step 2.
Calcium ions (Ca+) are reabsorbed by the sarcoplasmic reticulum
Relaxation step 3.
Muscle returns to normal length