Why Are Action Potentials Usually Conducted in One Direction

question 61

Multiple Choice

Why are action potentials usually conducted in one direction?

• A) The nodes of Ranvier conduct potentials in one direction.
• B) The brief refractory period prevents reopening of voltage-gated sodium channels.
• C) The axon hillock has a higher membrane potential than the terminals of the axon.
• D) Voltage-gated channels for both Na⁺ and K⁺ open in only one direction.

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Definitions:

Wave Summation

A phenomenon in muscle physiology where successive stimuli result in stronger muscle contractions than a single stimulus.

Treppe

A phenomenon observed in muscle contractions where consecutive stimulations result in progressively stronger contractions, resembling a staircase.

Dynamometry

The measurement of forces generated by muscles, often using a device to assess hand grip or muscle strength.

EMG

Electromyography is a diagnostic method used for evaluating the condition of muscles and the nerve cells responsible for their control.