The nurse is planning to instruct a group of adolescents on ways to prevent traumatic brain injuries. What should be included in these instructions?

Choice A Reason:
The facial nerve, or cranial nerve VII, is responsible for the taste sensation in the anterior two-thirds of the tongue, not the posterior third. It carries taste sensations from the front part of the tongue via the chorda tympani branch.

Choice B Reason:
The abducens nerve, or cranial nerve VI, has no role in taste sensation. It is primarily involved in controlling the lateral rectus muscle of the eye, which abducts the eye.

Choice C Reason:
The glossopharyngeal nerve, or cranial nerve IX, provides special sensory innervation for taste to the posterior third of the tongue. This enables the sensation of various tastes like salty, sweet, sour, and bitter in this region.

Choice D Reason:
The hypoglossal nerve, or cranial nerve XII, is responsible for motor control of the tongue muscles but does not provide sensory innervation for taste.

Choice A Reason:
The nasolacrimal sac is part of the tear drainage system. When a patient presents with excessive tearing, known as epiphora, it is important to assess for any obstruction in the lacrimal apparatus. The nasolacrimal sac can become blocked due to various reasons such as infection, inflammation, or structural abnormalities. Assessing this area can help determine if there is a blockage causing the tears to accumulate and overflow.

Choice B Reason:
Inspecting the palpebral conjunctiva is typically done if there is a complaint of eye pain or a sensation of a foreign body in the eye. While it is part of a comprehensive eye examination, it is not the first assessment to be performed for excessive tearing unless there are additional symptoms that suggest a problem with the conjunctiva.

Choice C Reason:
Testing the pupillary reaction to light is an assessment of the pupillary response and the function of the oculomotor nerve. This test is crucial when neurological issues are suspected or if there is a change in vision. However, it is not the primary assessment for excessive tearing without other associated symptoms.

Choice D Reason:
The eye positions test, which assesses eye muscle strength and cranial nerve function, is not necessary unless there are signs of problems with muscle strength, such as drooping. This test would not typically be the next step in assessing a patient with excessive tearing unless there are other indications of muscle or nerve impairment.