Reviewed by MedQGo Editorial Team | Last updated: July 30, 2026
The main factor affecting the amplitude of a nerve fiber action potential is
Astimulus intensity
Bduration of stimulus
Cconcentration of K+ on both sides of the cell membrane
Dconcentration of Na+ on both sides of the cell membrane
Correct answer: D. concentration of Na+ on both sides of the cell membrane
The amplitude of a nerve fiber action potential is primarily determined by the concentration difference of sodium ions (Na+) across the cell membrane. Changes in this concentration gradient affect the magnitude of the generated action potential.
Free PDF sample
Get NEET Biology MCQs as a chapter-wise PDF.
Join early access for a free MCQ sample with answers and NCERT-aligned explanations.