Question

A graded potential change that causes the resting membrane potential to change from -70 mv to -80 mv is __________.

a.an inhibitory postsynaptic potential (IPSP)

b.an excitatory postsynaptic potential (EPSP)

c.an action potential

d.facilitation

Answer 1

When the resting membrane potential shifts from -70 mv to -80 mv, this indicates an inhibitory postsynaptic potential (IPSP), which is a hyperpolarization that makes the neuron less likely to fire an action potential.

Step-by-step explanation:

A graded potential change that causes the resting membrane potential to change from -70 mv to -80 mv is an inhibitory postsynaptic potential (IPSP).

IPSP is the result of hyperpolarization and makes an action potential less likely to occur. This hyperpolarization can be caused by the efflux of K+ ions or the influx of Cl- ions, moving the membrane potential further from the threshold for triggering an action potential.

For example, when the neurotransmitter GABA is released, it binds to and opens Cl- channels on the postsynaptic neuron, allowing Cl- ions to enter the cell and hyperpolarize the membrane, thus generating an IPSP.