Chorda Tympani | Crack AIPGDEE Guidance

Chorda tympani, true is 
a) Carries P-sympathetic fibres to submandibular gland
b) Part of nerve of pterygoid canal
c) Sensory to tympanic membrane
D} Joins auriculotemporal nerve

Ans. (a) 

Regarding option b) Deep petrosal nerve is a branch of carotid plex LIS round internu I curotid artery. It joins the greater petrosal nerve to form nerve of pterygoid canal.

Regarding option c) Nerve supply of tympanic membrane 

Outer surface; the unrcroi nferior pan is supplied by auriculo temporal nerve and tile posterosuperior part by the auricular branch of vagus nerve.

Inner surface: this is supplied by the tympanic branch of the glossopharyngeal nerve through the tympanic plexus.

Option d) It joins the lingual nerve. not to auriculotemporal nerve.

Now regarding optiun a) 

Chorda tympani carries (a) preganglionic secretomotor fibres to the submandibular ganglion for supply of' submandibular and Sublingual salivary glands; and taste fibres from the anterior 213"" of tongue.

Submandibular ganglion = this is a parasympathetic peripheral ganglion. It is a relay station for secretomotor fibres to the submandibular and sublingual salivary glands.