Suppose you have three water baths in front of you. The temperature of the one on the left is 22°C (cold), the one in the middle is 25°C (room temperature), and the one on the right is 44°C (warm). At the same time, you place the index finger of your
right hand into the warm water bath and the index finger of your left hand into the cold water bath, and you leave them there for 2 minutes. After 2 minutes, why would you no longer feel a difference in temperature between the two water baths?
A) The sensory receptors in your index fingers speed up the conversion of the stimulus (water) to a chemical signal.
B) The sensory receptors in your index fingers diminish the conversion of the stimulus (water) to an electrical signal.
C) The sensory receptors in your index fingers become less sensitive over time as they are stimulated repeatedly.
D) Receptor potentials in the sensory receptors in your index fingers start off weak and then become stronger.
Answer: C
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