https://padlet.com/crydol009/braq4u3kn359 en-us 2018-01-12 15:03:15 UTC 2023-04-16 12:57:15 UTC hello@padlet.com crydol009 https://padlet.com/crydol009/braq4u3kn359/wish/221717524   The brain sends a nerve impulse down the Neuromuscular Junction. Nerve impulses causes voltage gated calcium ion channels to open and that allows calcium to enter the neuron. The increase in calcium releases acetylcholine (Ach) into the cleft. Ach binds to Ach receptor and activates voltage gated sodium channels which pumps Na+ in and K+ out. Since more Na+ is pumped into the cell it will become depolarized. Depolarization spreads to adjacent areas, opening voltage gated sodium channels and starting an action potential that moves along the sarcolemma. Na+ concentrations stimulate a change in the membrane by opening voltage- gated K+ pumps which allows K+ to diffuse across the sarcolemma out of the muscle fiber. This is called repolarization.]]> 2018-01-16 14:36:30 UTC https://padlet.com/crydol009/braq4u3kn359/wish/221717524 crydol009 https://padlet.com/crydol009/braq4u3kn359/wish/221717623 Step 1:  The action potential moves down the sarcolemma and down the T tubules.

 

]]> 2018-01-16 14:36:43 UTC https://padlet.com/crydol009/braq4u3kn359/wish/221717623 crydol009 https://padlet.com/crydol009/braq4u3kn359/wish/221718432 Step 2: Transmission of the action potential along the T tubules cause the adjacent sarcoplasmic reticulum to release Ca2+ which flows into the cytosol]]> 2018-01-16 14:38:38 UTC https://padlet.com/crydol009/braq4u3kn359/wish/221718432 crydol009 https://padlet.com/crydol009/braq4u3kn359/wish/221718551 Step 3 & 4 : Ca2+ combines with troponin and removes the blocking action of tropomyosin by changing the shape of the actin so that the myosin binding site are exposed.

]]> 2018-01-16 14:38:52 UTC https://padlet.com/crydol009/braq4u3kn359/wish/221718551 crydol009 https://padlet.com/crydol009/braq4u3kn359/wish/221718601 step 1: cross bridge formation. Energized myosin head attaches to an myofilament forming a cross bridge

]]> 2018-01-16 14:38:57 UTC https://padlet.com/crydol009/braq4u3kn359/wish/221718601 crydol009 https://padlet.com/crydol009/braq4u3kn359/wish/221719904 Step 4: As ATP is split into ADP and P, the myosin head is energized (cocked into the high-energy conformation)]]> 2018-01-16 14:42:01 UTC https://padlet.com/crydol009/braq4u3kn359/wish/221719904 crydol009 https://padlet.com/crydol009/braq4u3kn359/wish/221721476 step 2: Inorganic phosphate is released, starting the power (working) stroke. The myosin head moves and bends as it pulls on the actin, sliding it toward the M line. ADP is released. ]]> 2018-01-16 14:45:26 UTC https://padlet.com/crydol009/braq4u3kn359/wish/221721476 crydol009 https://padlet.com/crydol009/braq4u3kn359/wish/221721734 Step 3: As new ATP attaches to the myosin head, the link between myosin and actin weakens, and the cross bridge detaches]]> 2018-01-16 14:46:00 UTC https://padlet.com/crydol009/braq4u3kn359/wish/221721734