Sensory nerve supply to the base of the tongue:

 # Sensory nerve supply to the base of the tongue:

A. Facial nerve

B. Trigeminal nerve

C. Glossopharyngeal nerve

D. Optic nerve

The correct answer is C. Glossopharyngeal nerve.

The hypoglossal nerve (CN XII) provides motor innervation to all of the intrinsic and extrinsic muscles of the tongue except for the palatoglossus muscle, which is innervated by the vagus nerve (CN X). It runs superficial to the hyoglossus muscle. Lesions of the hypoglossal nerve cause deviation of the tongue to the ipsilateral (i.e., damaged) side.

Taste to the anterior two-thirds of the tongue is achieved through innervation from the chorda tympani nerve, a branch of the facial nerve (CN VII). General sensation to the anterior two-thirds of the tongue is by innervation from the lingual nerve, a branch of the mandibular branch of the trigeminal nerve (CN V3). The lingual nerve is located deep and medial to the hyoglossus muscle and is associated with the submandibular ganglion.

On the other hand, taste perception in the posterior third of the tongue is accomplished through innervation from the glossopharyngeal nerve (CN IX), which also provides general sensation to the posterior one-third of the tongue. Taste perception also is performed by both the epiglottis and the epiglottic region of the tongue, which receives taste and general sensation from innervation by the internal laryngeal branch of the vagus nerve (CN X). Damage to the vagus nerve (CN X) causes contralateral deviation (away from the injured side) of the uvula.

Reference: Dotiwala AK, Samra NS. Anatomy, Head and Neck, Tongue. [Updated 2022 Aug 27]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK507782/

Sensory nerves supply to the body of the tongue:

 # Sensory nerves supply to the body of the tongue:

A. Optic nerve

B. Trigeminal nerve

C. Facial nerve

D. Glossopharyngeal nerve

The correct answer is B. Trigeminal nerve.

The hypoglossal nerve (CN XII) provides motor innervation to all of the intrinsic and extrinsic muscles of the tongue except for the palatoglossus muscle, which is innervated by the vagus nerve (CN X). It runs superficial to the hyoglossus muscle. Lesions of the hypoglossal nerve cause deviation of the tongue to the ipsilateral (i.e., damaged) side.

Taste to the anterior two-thirds of the tongue is achieved through innervation from the chorda tympani nerve, a branch of the facial nerve (CN VII). General sensation to the anterior two-thirds of the tongue is by innervation from the lingual nerve, a branch of the mandibular branch of the trigeminal nerve (CN V3). The lingual nerve is located deep and medial to the hyoglossus muscle and is associated with the submandibular ganglion.

On the other hand, taste perception in the posterior third of the tongue is accomplished through innervation from the glossopharyngeal nerve (CN IX), which also provides general sensation to the posterior one-third of the tongue. Taste perception also is performed by both the epiglottis and the epiglottic region of the tongue, which receives taste and general sensation from innervation by the internal laryngeal branch of the vagus nerve (CN X). Damage to the vagus nerve (CN X) causes contralateral deviation (away from the injured side) of the uvula.

Reference: Dotiwala AK, Samra NS. Anatomy, Head and Neck, Tongue. [Updated 2022 Aug 27]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK507782/

From which arch is hypobranchial eminence derived?

 # Hypobranchial eminence is derived from:

A. 1st arch 

B. 2nd arch

C. 3rd arch 

D. 4th arch

The correct answer is C. 3rd arch.

During embryonic development, the pharyngeal arches play a crucial role in the formation of various structures in the head and neck region. The third pharyngeal arch gives rise to several important structures, including the hyoid bone, the posterior one-third of the tongue (base of the tongue), and the associated muscles and nerves.

The hypobranchial eminence is a swelling within the third pharyngeal arch that contributes to the formation of the base of the tongue. It gives rise to the posterior part of the tongue, while the anterior part of the tongue is formed by the first pharyngeal arch.

Therefore, the correct option is C. 3rd arch.

Development of coronoid process of mandible occurs at:

 # Development of coronoid process of mandible occurs at:

A. 10-12 weeks 

B. 12-16 weeks

C. 10-14 weeks 

D. 14-16 weeks

The correct answer is C. 10-14 weeks.

The development of the coronoid process of the mandible occurs during the embryonic period of gestation. Specifically, it takes place between 10 and 14 weeks of gestation. Therefore, the correct option is C. 10-14 weeks.

During this time frame, the mandible undergoes various developmental processes, including the formation of the mandibular body, the ramus, and the coronoid process. The coronoid process is a bony prominence located on the anterior aspect of the ramus of the mandible. It serves as an attachment site for muscles involved in chewing and jaw movement.

Options A and B (10-12 weeks and 12-16 weeks) and Option D (14-16 weeks) do not accurately represent the developmental period when the coronoid process of the mandible forms. The correct time frame is 10-14 weeks.