This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Physiology
All or none law is obeyed by: March 2005 
Select and explain. 
A. Post synaptic potential, B. Non propagated potential, C. Action potential, D. Spike potential
C: Action potential
Answer: C: Action potential 
Explanation: Ans. C: Action potentialOnce threshold intensity is reached, a full fledged action potential is produced.The action potential fails to occur if the stimulus is subthreshold in magnitude and it occurs with constant amplitude and form, regardless of the strength of the stimulus if the stimulus is at or above threshold intensity. Therefore action-potential obeys all or none law