Question

A neuron has a resting potential of about _____ millivolts.

+50
+35
–55
–70
–80

Answer 1

A neuron has a resting potential of about -70 millivolts (mV) caused by differences in ion concentrations inside and outside the cell. The negative charge is created and maintained by the selective permeability of the cell membrane.

Step-by-step explanation:

A neuron at rest has a resting potential of about -70 millivolts (mV). This voltage, also known as the resting membrane potential, is caused by differences in the concentrations of ions inside and outside the cell. The negative charge inside the cell is created and maintained by the selective permeability of the cell membrane, which allows potassium ions (K+) to move out of the cell more freely than sodium ions (Na+) to move in. This difference in charge enables neurons to respond to chemical and electrical signals.

Answer 2

A neuron has a resting potential of about -70 millivolts.

The resting membrane potential is stable potential that each neuron has at rest and it is determined:

• By concentration gradients of ions across the membrane

• by membrane permeability to each type of ion (potassium, sodium, calcium, and chloride ions).

Voltage of neuron membrane is actually a difference in electric potential between positive and negative electric charges on opposite sides of a plasma membrane (inside of the cell is more negative than the outside). So, we say that the membrane is polarized.

If the membrane potential becomes more positive than it is at the resting potential, it becomes depolarized. Otherwise, it is hyperpolarized.