- A It directly destroys the entire neuron cell body along with its nucleus and cellular organelles in routine practice
- B Loss of myelin sheath converts saltatory conduction to slow continuous conduction; threshold may not be reached at nodes
- C It pharmacologically blocks voltage-gated sodium channels distributed along the entire axon membrane overall in most cases
- D It substantially increases resting membrane permeability specifically to potassium ions present under typical conditions
Correct answer: B. Loss of myelin sheath converts saltatory conduction to slow continuous conduction; threshold may not be reached at nodes
Explanation: Myelin loss: action potential must continuously depolarize the axon membrane (continuous conduction) rather than jumping between nodes. Much slower, and in severe demyelination, signal can fail to propagate entirely.
Concept context
Brain, spinal cord, neurons, reflex arcs, and sense organs.