correct order of events in the neuromuscular transmission in skeletal muscle
Question
correct order of events in the neuromuscular transmission in skeletal muscle
Solution
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The process begins when an action potential (electrical signal) is sent down a motor neuron.
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The action potential reaches the axon terminal of the neuron, causing voltage-gated calcium channels to open.
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The influx of calcium into the neuron triggers the release of acetylcholine (ACh), a neurotransmitter, into the synaptic cleft.
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Acetylcholine diffuses across the synaptic cleft and binds to nicotinic receptors on the motor end plate of the skeletal muscle fiber.
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The binding of acetylcholine to its receptors causes sodium channels to open, allowing sodium ions to flow into the muscle fiber.
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The influx of sodium ions depolarizes the muscle fiber, triggering an action potential in the muscle.
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The action potential travels along the muscle fiber and into the T-tubules, triggering the release of calcium ions from the sarcoplasmic reticulum.
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The released calcium ions bind to troponin, causing a conformational change that moves tropomyosin away from the active sites on actin.
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This allows myosin heads to bind to actin, forming cross-bridges.
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The myosin heads pull on the actin filaments, causing the muscle to contract.
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After the contraction, the calcium ions are pumped back into the sarcoplasmic reticulum, and the muscle relaxes.
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Acetylcholine in the synaptic cleft is broken down by acetylcholinesterase, ending the signal transmission.
Similar Questions
medical student was doing research in a laboratory that studiesthe neuromuscular junction. Which of the following events atthe junction are listed in correct sequential order?A. Motor neuron action potential, acetylcholine release, Na+entry at the endplateB. Ca2+ entry into the motor nerve terminal, Na+ entry at theendplate, muscle fiber action potentialC. Na+ entry at the endplate, acetylcholine release, muscle fiberaction potentialD. Motor neuron action potential, Na+ entry at the endplate,formation of an endplate potentialE. Ca2+ entry into the motor nerve terminal, acetylcholinerelease, Na+ entry at the endplate
Which of the following events in muscle contraction is the last to occur chronologically? The T-tubules depolarize, causing calcium to be released from the sarcoplasmic reticulum. Calcium is taken up into the sarcoplasmic reticulum. Tropomyosin moves, exposing the actin active sites. ATP binds to the myosin head allowing it to release from actin.
he following is a list of the events that occur during a muscle contraction.1. Myosin cross-bridges bind to the actin.2. The free myosin head splits ATP.3. Calcium ion is released from the sarcoplasmic reticulum.4. The myosin head pivots toward the center of the sarcomere.5. Calcium ion binds to troponin.6. The myosin head binds an ATP molecule and detaches from the actin.The correct sequence of these events isQuestion 10Select one:a.3, 5, 1, 2, 4, 6.b.1, 3, 5, 4, 6, 2.c.1, 4, 6, 2, 3, 5.d.3, 5, 1, 4, 6, 2.e.5, 1, 4, 6, 2, 3.
The neurotransmitter released at neuromuscular junctions, stimulating skeletal muscle contraction, is .
The autonomic nervous system acts on smooth and skeletal muscle.Group of answer choicesTrueFalse
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