Skeletal Muscle System

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The skeletal muscle system is made of many skeletal muscle fibers which have at least one neuromuscular junction. A neuromuscular junction is the area of the skeletal muscle fiber that is innervated by a motor neuron (motor nerve). It plays a key role in body movement and breathing along with our nervous system. The synaptic knob, motor end plate, and the synaptic cleft are all key parts of the neuromuscular junction. The synaptic knob of an axon connects with a skeletal muscle fiber to form the neuromuscular junction. The synaptic knob has numerous synaptic vesicles that are filled with the neurotransmitter acetylcholine. The synaptic knob also contains calcium pumps and voltage-gated calcium channels. The calcium pumps within the synaptic …show more content…
and then travels to the end of the motor neuron. The motor end plate is protected by a phospholipid bilayer that has acetylcholine receptors that allow acetylcholine to flow from the synaptic cleft into the motor end plate. When acetylcholine attaches to the acetylcholine receptors, it activates sodium channels to open. Sodium channels open and let positively charged sodium ions rapidly into the motor end plate, while potassium ions are slowly kicked out of the charged environment in the motor end plate. This is the first step of skeletal muscle fiber excitation, where our nervous system sends a nerve signal to our muscle fibers to go from a relaxed position to a contracted position by producing tension on the skeletal muscle of an area to cause the body to move. This will continue to happen if the neuron continues to send a nerve

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