Question

Which of the following statements is FALSE regarding the steps related to strengthening of a glutamatergic synapse A. Low frequency of glutamate release from the presynaptic neuron that activates AMPA receptors is the initiating signal that starts the process of strengthening the synapse B. Depolarization of the membrane by AMPA receptors (magnesium ion pushed out of the channel), combined with the binding of glutamate and glycine will cause the NMDA receptor to activate C. Activation of the NMDA receptor allows both sodium and calcium to enter the inside of the post synaptic cell D. High concentrations of calcium inside the post-synaptic dendrite will act similar to a second messenger interacting with a variety of things inside of cell resulting in more AMPA receptors being integrated into the postsynaptic membrane E. Following strengthening of the synapse future glutamate release will generate larger EPSPs compared to the size of EPSPs caused by an equal amount of glutamate prior to the process of strengthening the synapse

Answer 1

Option A is the false statement regarding the steps related to the strengthening of a glutamatergic synapse.

Step-by-step explanation:

The statement that is FALSE regarding the steps related to the strengthening of a glutamatergic synapse is option A: "Low frequency of glutamate release from the presynaptic neuron that activates AMPA receptors is the initiating signal that starts the process of strengthening the synapse".

1. Option A is false because the high frequency, not low frequency, of glutamate release from the presynaptic neuron that activates AMPA receptors is the initiating signal that starts the process of strengthening the synapse.

2. Options B, C, D, and E are all true statements regarding the steps related to strengthening of a glutamatergic synapse.

Answer 2

The false statement is A, as strengthening a glutamatergic synapse through long-term potentiation requires high-frequency stimulation to initiate the process, not low-frequency stimulation as mentioned.

Step-by-step explanation:

The statement that is FALSE regarding the steps related to strengthening of a glutamatergic synapse is A. Low frequency of glutamate release from the presynaptic neuron that activates AMPA receptors is the initiating signal that starts the process of strengthening the synapse.

In fact, strengthening a synapse through long-term potentiation (LTP) typically requires high-frequency stimulation rather than low-frequency stimulation. This high-frequency stimulation leads to sufficient depolarization of the postsynaptic membrane to remove the magnesium ion from NMDA receptors and allow calcium to flow into the cell, contributing to the induction of LTP.

Once the NMDA receptor is activated, it does indeed allow both sodium and calcium to enter the inside of the post synaptic cell, and the high concentrations of calcium inside the post-synaptic dendrite act as a second messenger. This initiates a variety of intracellular events, eventually resulting in more AMPA receptors being integrated into the postsynaptic membrane. As a result of this strengthening, future glutamate release will generate larger excitatory postsynaptic potentials (EPSPs), making the postsynaptic neuron more likely to fire in response to neurotransmitter release.