National University Muscle Physiology Questions
QUESTION 3
The calcium channel in the SR is considered to be gated. That calcium channel is specifically requires does not require ACh calcium chemically closes mechanically opens sodium and potassium SR membrane t-tubules voltage -gated. That means that it requires does not require ACh calcium chemically closes mechanically opens sodium and potassium SR membrane t-tubules voltage when the action potential runs along the requires does not require ACh calcium chemically closes mechanically opens sodium and potassium SR membrane t-tubules voltage . The gating of the channel requires does not require ACh calcium chemically closes mechanically opens sodium and potassium SR membrane t-tubules voltage ATP to occur.Meanwhile, on the postsynaptic membrane of the neuromuscular junction there are also gated channels. These are also called requires does not require ACh calcium chemically closes mechanically opens sodium and potassium SR membrane t-tubules voltage receptors. These channels are considered to be requires does not require ACh calcium chemically closes mechanically opens sodium and potassium SR membrane t-tubules voltage -gated. In order to open, it requires does not require ACh calcium chemically closes mechanically opens sodium and potassium SR membrane t-tubules voltage ATP. When these gated channels are open they allow requires does not require ACh calcium chemically closes mechanically opens sodium and potassium SR membrane t-tubules voltage to pass through them.
QUESTION 4
Please keep in mind that an answer can be used more than once.In a sarcomere there are both actin and myosin filaments. The actin filament myosin filament actin-binding site myosin-binding site ATP-binding site ATPase troponin head tail hinge has tropomyosin associated with it. When a muscle fiber is resting, the tropomyosin blocks the actin filament myosin filament actin-binding site myosin-binding site ATP-binding site ATPase troponin head tail hinge on each actin protein. After calcium is available, tropomyosin is tugged out of the way by actin filament myosin filament actin-binding site myosin-binding site ATP-binding site ATPase troponin head tail hinge . This enables each myosin actin filament myosin filament actin-binding site myosin-binding site ATP-binding site ATPase troponin head tail hinge group to attach to the thin filament with its actin filament myosin filament actin-binding site myosin-binding site ATP-binding site ATPase troponin head tail hinge . When the powerstroke occurs, the myosin protein bends at the actin filament myosin filament actin-binding site myosin-binding site ATP-binding site ATPase troponin head tail hinge on its neck. The powerstroke pulls on the entire actin filament myosin filament actin-binding site myosin-binding site ATP-binding site ATPase troponin head tail hinge so that the Z-lines are pulled inward. In order to do this again, another adenosine triphosphate molecule has to bind to the actin filament myosin filament actin-binding site myosin-binding site ATP-binding site ATPase troponin head tail hinge on the actin filament myosin filament actin-binding site myosin-binding site ATP-binding site ATPase troponin head tail hinge region of the myosin molecule so that the cross-bridge can disconnect. To become re-energized, the head group has to break down the ATP molecule using its actin filament myosin filament actin-binding site myosin-binding site ATP-binding site ATPase troponin head tail hinge function. Throughout this entire time, the actin filament myosin filament actin-binding site myosin-binding site ATP-binding site ATPase troponin head tail hinge region of the myosin molecules are not doing anything but remaining stuck within the actin filament myosin filament actin-binding site myosin-binding site ATP-binding site ATPase troponin head tail hinge to hold all the myosin molecules together.
QUESTION 6
Examine the steps below and put them in the correct order.
– 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. Calcium unbinds from the troponin
– 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. An action potential is generated in the muscle fiber
– 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. Power stroke carried out by myosin heads
– 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. Calcium ions bind to troponin allowing formation of cross bridges
– 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. DHP receptor changing shape causes calcium ion to be released from the sarcoplasmic reticulum into the cytosol.
– 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. ACh levels rise in the neuromuscular junction
– 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. Myosin heads release and elastic filaments pull filaments back to relaxed position.
– 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. Na+ enters into the muscle fiber through ACh receptor channels.
– 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. Calcium ions are pumped by active transport into sarcoplasmic reticulum
– 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. Action potential travels along sarcolemma and t-tubules causing the DHP receptor to change shape