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Describe step by step how a signal is transmitted from your brain and nervous system into an actual contraction of the muscles. Your explanation should start at the stage where the nervous system interacts with the muscles and should discuss the role of the neuromuscular junction, neurotransmitter, and motor neurons.

User Kosh
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Answer:

A Muscle Contraction Is Triggered When an Action Potential Travels Along the Nerves to the Muscles. Muscle contraction begins when the nervous system generates a signal. The signal, an impulse called an action potential, travels through a type of nerve cell called a motor neuron.

Step-by-step explanation:

User StuartDTO
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Step-by-step explanation:

The first step is the muscle fiber is activated by the motor neuron when the acetylcholine crosses the synaptic gap, which causes the heads of the myofibrils to bind. This activation initiates by the release of calcium ions within the muscle fibers. The neuromuscular junction furthers the reaction by assisting in message transmission, along with the neurotransmitter which helps with transmitting messages between neurons and the muscles.

Second, the myofibril binds to the next myofibril in a chain-like reaction.

Third, as one myofibril joins the next, they shorten and slide closer together, causing the muscle to contract.

Fourth, the contraction ends when the acetylcholine breaks down through its natural cycle.

(I'm pretty sure that this is correct, I'm sorry if it is not)

User Zach Waugh
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