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AMPA receptor,When does it open?

A) In the absence of neurotransmitters; Sodium ions; Hyperpolarization
B) Upon binding of glutamate; Calcium ions; Depolarization
C) During REM sleep; Potassium ions; Repolarization
D) In stressful situations; Chloride ions; No change in membrane potential

User Trk
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Final answer:

AMPA receptors open upon the binding of glutamate, allowing sodium ions (Na+) to enter the postsynaptic neuron and trigger depolarization, which may lead to an action potential if the threshold is reached. This plays a key role in synaptic plasticity and memory formation.

Step-by-step explanation:

AMPA receptors open upon the binding of glutamate, which is a neurotransmitter. These receptors help in the depolarization process of the postsynaptic neuron when they allow sodium ions (Na+) to enter the cell. This depolarization is a decrease in the voltage difference between the inside and outside of the neuron, initiating an action potential if the depolarization reaches the threshold potential. The AMPA receptors are involved in synaptic transmission and contribute significantly to brain functions such as cognition and action, playing a critical role in synaptic plasticity and memory formation.

Once bound with glutamate, AMPA receptors quickly allow sodium ions to enter and depolarize the postsynaptic neuron. Following depolarization, voltage-gated potassium channels (K+) open to allow potassium to leave the cell, which returns the cell to its resting membrane potential through repolarization. Additionally, calcium ions (Ca2+) flowing through neighboring NMDA receptors may trigger further intracellular events, demonstrating the complexity and coordination of ion channels in neuronal communication.

User Micadelli
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