Chapter 10 -Steps for muscle contrition

Question 1

what is step 1 of muscle contraction?

Answer 1

action potential travels down the axon of the motor neuron to the synaptic knob

Question 2

What is step 2?

Answer 2

calcium ion channels open , which causes calcium ions to enter the synaptic knob and triggers exocytosis of Acetocholine from the synaptic vesicles

Question 3

what is step 3

Answer 3

Acetocholine diffuses across the synaptic cleft and binds to Acetocholine receptors on motor end plate

Question 4

step 4

Answer 4

sodium ions enter the muscle fiber through open chemically gated ion channels causing depolarization

Question 5

step five

Answer 5

reach threshold, causing action potential to spread across the sarcoma and transverse tubules

Question 6

step 3

Answer 6

open voltage gated ion channels in sarcoplasmic reticulum releasing calcium ions into the sarcoplasm

Question 7

step 7

Answer 7

calcium ions bind to troponin causing it to change shape and move tropomyosin exposing myosin biding sites

Question 8

step 8

Answer 8

myosin heads binds to actin forming a crossbridge and pulls towards the M line

Question 9

step 9

Answer 9

release myosin head, recock it using ATP and repeat step 8 until no more signal is being sent