Question
Each of the figures in the diagram below illustrates a train of action potentials in response to a sudden limb movement. The sensory neuron encoding the velocity of the limb movement is illustrated by which figure?
| A. |
Figure A |
| B. |
Figure B |
| C. |
Figure C |
| D. |
Figure D |
Show Answer
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Correct Answer � B Explanation |
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Ans. B. Figure B
- A phasic receptor (rapid adaptation), illustrated by figure B, produces a high frequency burst of action potentials when stimulated.
- The frequency of discharge slows down or stops even though the stimulus is maintained.
- In contrast, a tonic receptor, illustrated in A and C, continues to fire at a frequency proportional to the magnitude of the stimulus for as long as the stimulus is applied.