Question

Which of the following cranial nerves allows one to taste a lemon and then make a face because it is sour?

1. Trigeminal
2. Facial
3. Abducens
4. Glossopharyngeal

Answer 1

The cranial nerve responsible for tasting a lemon and reacting to its sourness is the facial nerve (cranial nerve VII), which serves both gustatory sensation and motor functions for facial expressions.

Step-by-step explanation:

The cranial nerve responsible for both tasting a lemon and making a face because it is sour is the facial nerve (cranial nerve VII). This nerve facilitates the sense of taste in the anterior two-thirds of the tongue and also controls the facial expressions you make, including the reaction to sour tastes. The cranial nerve responsible for taste is the glossopharyngeal nerve.This nerve connects to taste buds in the posterior two thirds of the tongue.

So, the correct answer is b. glossopharyngeal.When tasting something sour like a lemon, the gustatory cells in the taste buds are activated and release neurotransmitters onto the sensory neurons that are part of the facial nerve. The facial nerve then conveys the taste sensations to the brain. The facial nerve also contains motor fibers that instruct your facial muscles to contract, creating a facial expression reflective of the sour taste. The sour taste typically causes a person to pucker their lips and squint their eyes, which are movements controlled by the facial nerve.