Question

The electrical potential difference across the plasma membrane of a neuron during conduction of nerve impulse is known as

• A. Excitation potential
• B. Impulse potential
• C. Resting potential
• D. Action potential

Answer 1

The correct option is D Action potential

The potential difference between inside and outside of axon at resting stage (when it is not conducting nerve impulse) is known as resting potential. The axon membrane is said to be polarized with negative charge (-60 mV) prevailing inside.

Release of neurotransmitters from synaptic vesicles in synaptic cleft and their binding to the membrane of postsynaptic neuron is followed by depolarization of postsynaptic neuron membrane. Depolarization of membrane leads to movement of $N{a}^{+}$ ions inside the axon membrane and that of $K^{+}$ ions outside the membrane via ATP energized pump to make the inside of axon positively charged (+60mV). This electrical potential is known as excitatory postsynaptic potential.

Action potential is the excitatory potential critically enough to support impulse conduction.

Therefore, the correct answer is option D.