NEET
- Exam
- NEET
- Subject
- Zoology
- Chapter
- Neural Control and Coordination
NEET · Zoology · Neural Control and Coordination
What is the action potential of the plasma membrane of a neuron?
What is the action potential of the plasma membrane of a neuron?
Options
- AThe electrical potential difference across the plasma membrane when the neuron is resting.
- BThe electrical potential difference across the plasma membrane at the site of excitation when the membrane is depolarised.
- CThe electrical potential difference across the plasma membrane when the membrane is in a non-polarised state.
- DThe electrical potential difference across the plasma membrane when the membrane is in a polarised state.
Correct answer
B. The electrical potential difference across the plasma membrane at the site of excitation when the membrane is depolarised.
Step-by-step solution
The outer surface of the axonal membrane possesses a positive charge while its inner surface becomes negatively charged and therefore is polarised The sodium-potassium pump transports 3 Na⁺ ions outwards for 2 K⁺ ions into the cell.The action potential is generated in response to a stimulus and travels along the length of the axon, transmitting the nerve impulse. The rise in permeability to Na⁺ is short-lived and is followed by a rise in permeability to K⁺. K⁺ diffuses outside the membrane, restoring the resting potential of the membrane.