Neuromuscular Junction

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Neuromuscular junctions are important for joining skeletal muscle fibers and motor neurons together. These junctions link the muscle and nervous system to one another. A motor neuron is a nervous cell that controls the contraction or relaxation of muscles. Motor neurons are also referred to as efferent neurons. Efferent neurons carry information from the CNS to the muscle system and other systems. The neuron is composed of 3 different parts: the dendrites, soma (cell body) and the axon. The dendrite branches away from the cell body and receives signals from other parts of the nervous system. The soma or cell body allows form the neuron/cell to remain functional. This includes maintaining the genetic information and cell components. The axon…show more content…
The neuromuscular junction is where an electric impulse travels to instruct the muscle system to make a move. A neuromuscular junction consists of an axon terminal of a motor neuron and the motor end plate of a muscle fiber. The axon terminal splits into multiple tiny branches, each ending in a bulblike structures, named the terminal button. The motor end plate houses the entire axon terminal. The synaptic cleft corresponds to the tiny gap between the axon terminals and the sacrolemma (the plasma membrane of the muscle fiber). The neuron contains neurotransmitters that are transmitted through the neuromuscular junction (by way of the terminal buttons) into the muscle fiber. There are receptors specific for the neurotransmitter that is binding to the muscle fiber. This could be described as a lock and key relationship, where only a specific key will fit into a specific…show more content…
Clostridium botulinum toxin causes botulism, which is a form of food poisoning. When this toxin is ingested, muscles are inhibited to responding to nerve impulses. Death is caused by respiratory failure, due to not being able to contract the diaphragm. It constantly remains at rest. Botulinum toxin is the most lethal poison known, the smallest amount ~0.0001 mg can kill an adult human. [see figure 4]Curare binds to the ACh receptor channels on the motor end plate. It can not be inactivated by AChE. When the receptors are bound to curare, ACh can not combine and open the channels which would create an end plate potential. The result is paralysis due to muscle action potentials not being created. When there is a significant amount of curare that has blocked a magnitude of ACh receptors, the person dies due to respiratory failure, caused by the constant resting state of the diaphragm. There is no

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