A patient has extremely enlarged palatine tonsils. You suggest surgical removal of the tonsils, but you do explain that there is a small risk of the surgery, which may result in which of the following?
**Core Concept**
The question tests the student's knowledge of the anatomy of the tongue and the nerves involved in taste and swallowing. Specifically, it requires an understanding of the vagus nerve's role in innervating the posterior one-third of the tongue and the relationship between the vagus nerve and the pharynx.
**Why the Correct Answer is Right**
The correct answer involves the risk of damage to the glossopharyngeal nerve (cranial nerve IX) during tonsillectomy. The glossopharyngeal nerve is responsible for transmitting taste sensations from the posterior one-third of the tongue. Additionally, the vagus nerve (cranial nerve X) is also at risk of damage during the procedure, particularly in relation to the pharyngeal plexus, which can lead to difficulty in swallowing.
**Why Each Wrong Option is Incorrect**
* **Option A:** The ability to taste salt is mediated by the chorda tympani, a branch of the facial nerve (cranial nerve VII), which is not at risk during tonsillectomy.
* **Option B:** The extrinsic muscles of the tongue, including the genioglossus, are innervated by the hypoglossal nerve (cranial nerve XII), which is not typically damaged during tonsillectomy.
* **Option C:** The lateral pterygoid muscle is innervated by the mandibular division of the trigeminal nerve (cranial nerve V3), which is not directly related to the risks of tonsillectomy.
**Clinical Pearl / High-Yield Fact**
The glossopharyngeal nerve is also responsible for the pharyngeal branch of the otic ganglion, which provides parasympathetic innervation to the parotid gland. Damage to this nerve can lead to a decrease in saliva production.
✓ Correct Answer: D. Loss in the ability to taste in the posterior one-third of the tongue and perhaps some difficulty in swallowing