Assume a Hypothetical Postsynaptic Neuron Has Three Presynaptic Inputs, X

question 21

Multiple Choice

Assume a hypothetical postsynaptic neuron has three presynaptic inputs, X, Y, and Z.When presynaptic neurons X and Y are stimulated simultaneously, the postsynaptic neuron reaches threshold and undergoes an action potential.Yet, when presynaptic neurons X and Z are stimulated simultaneously, there is no change in potential of the postsynaptic neuron.Which of these statements describes the presynaptic neurons Y and Z

• A)Presynaptic neurons Y and Z are both excitatory.
• B)Presynaptic neurons Y and Z are both inhibitory.
• C)Presynaptic neuron Y is excitatory, and presynaptic neuron Z is inhibitory.
• D)Presynaptic neuron Y is inhibitory, and presynaptic neuron Z is excitatory.

---

Definitions:

Tympanostomy Tubes

Small tubes inserted into the eardrum to allow air to enter the middle ear, used to treat recurrent ear infections or fluid buildup.

Sensorineural Loss

Hearing loss resulting from damage to the inner ear or the nerve pathways from the inner ear to the brain.

Surgical Procedure

A medical intervention involving an incision with instruments, performed to repair damage or arrest disease in a living body.

Inner Ear

The innermost part of the ear, containing the cochlea, vestibule, and semicircular canals, responsible for hearing and balance.