At an Excitatory Synapse, an Action Potential in the

question 168

Multiple Choice

At an excitatory synapse, an action potential in the

• A) postsynaptic neuron depolarizes the presynaptic cell membrane.
• B) presynaptic neuron increases the permeability of the subsynaptic membrane of the postsynaptic cell to both Na⁺ and K⁺.
• C) presynaptic neuron increases the permeability of the subsynaptic membrane of the postsynaptic cell to K⁺ only.
• D) both (a) and (b) above.
• E) both (a) and (c) above.

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Definitions:

Optic Disk

The point of exit for the fibers of the optic nerve on the retina, lacking light-sensitive photoreceptor cells, thus creating the "blind spot".

Macula Lutae

A small, yellowish spot located near the center of the retina of the eye, responsible for high-acuity vision.

Fovea

A small depression in the retina where visual acuity is highest.

Astigmatism Test Chart

A visual tool used to assess the presence and degree of astigmatism, featuring lines or patterns to help determine visual distortions.