A muscle cell contains acetylcholine receptors that act as ligand-gated cation channels, and it also contains voltage-gated Na+ channels of the type found in neurons. In theory, could a muscle cell get away with having only acetylcholine-gated cation channels, which would serve the dual purpose of receiving neurotransmitter signals and propagating action potentials? Why or why not?

A muscle cell contains acetylcholine receptors that act as ligand-gated cation channels, and it also contains voltage-gated Na+ channels of the type found in neurons. In theory, could a muscle cell get away with having only acetylcholine-gated cation channels, which would serve the dual purpose of receiving neurotransmitter signals and propagating action potentials? Why or why not?

Human Physiology: From Cells to Systems (MindTap Course List)

9th Edition

ISBN:9781285866932

Author:Lauralee Sherwood

Publisher:Lauralee Sherwood

Chapter7: The Peripheral Nervous System: Efferent Division

Section: Chapter Questions

Problem 4RE

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hen an action potential arrives at the nerve terminal of a neuromuscular junction, which of the following statements best describes the events that occur? Depolarisation of the nerve terminal causes the release of ACh which activates nicotinic receptors on the skeletal muscle membrane to cause Ca2+ entry and muscle contraction. Depolarisation of the nerve terminal opens voltage-gated Ca2+ channels, Ca2+ entry brings vesicles containing ACh to the membrane which form fusion pores causing the release of ACh which activates voltage-gated Na+ channels at the end-plate. Depolarisation of the nerve terminal opens voltage-gated Ca2+ channels, Ca2+ entry brings vesicles containing ACh to the membrane which form fusion pores causing the release of ACh which binds to muscarinic receptors at the end plate. Depolarisation of the nerve terminal opens voltage-gated Ca2+ channels, Ca2+ entry brings vesicles containing ACh to the membrane which form fusion pores…
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Which of the following statements are true with regards to the differences between a neuromuscular junction, and a standard central nervous system (CNS) synapse? Select all that apply. O The neuromuscular junction is a synapse between a neuron (alpha motor neuron) and a muscle fibre. CNS synapses connect two neurons. The graded potential generated by a neuromuscular junction has a much larger voltage than that of a CNS synapse. The structure of the neuromuscular junction ensures that an action potential in the alpha motor neuron always results in an action potential in the post-synaptic muscle fibre. CNS synapses do not guarantee this. The neuromuscular junction always uses Acetylcholine as a neurotransmitter, whereas CNS synapses may use a variety of neurotransmitters depending on their location and function
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Predatory cone snails are beautiful (picture below), but deadly - they release a cocktail of toxins that affect multiple aspects of neuronal function. One of these toxins is called omega-conotoxin, and it blocks (inhibits) voltage-gated calcium channels. What impact would this have on chemical synaptic transmission? Action potentials cannot be initiated O b. Action potentials can be initiated, but cannot propagate down axons and thus cannot reach terminals O c. Action potentials can propagate and reach terminals, but neurotransmitter release is not possible o d. Neurotransmitters can be released from terminals, but they cannot bind to receptors O . Neurotransmitters can be released and can bind to receptors, but PSPS will not occur
are these True or False? Receptors on the post-synaptic cell membrane that bind the acetylcholine are voltage-gated channels (channels that open in response to a change in the electrical charge of the membrane). When a muscle cell is not contracting its cell membrane is negative on the inner surface. The effect of a neurotransmitter on the muscle cell membrane is to modify its ion permeability properties temporarily.
Are these true or false? Acetylcholine molecules are actively transported from the axon to their receptors on the muscle membrane by special transport proteins. Receptors on the post-synaptic cell membrane that bind the acetylcholine are voltage-gated channels (channels that open in response to a change in the electrical charge of the membrane). When a muscle cell is not contracting its cell membrane is negative on the inner surface. The effect of a neurotransmitter on the muscle cell membrane is to modify its ion permeability properties temporarily. During depolarization, a small region of the muscle cell's membrane becomes less negative on the inside." Both sodium and potassium are more concentrated in the extracellular fluid than the intracellular fluid. After an action potential passes over a region of the sarcolemma the region remains positively charged throughout the entire muscle contraction. An increase in the calcium ion level in the cytosol causes thin filaments to begin…
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