Question

Name the parasympathetic nerve from the brain that innervates most of the visual organs. List any four functions of this nerve.

Answer 1

Third cranial nerve, the oculomotor nerve has two components:

• The somatic motor component which supplies four extraocular muscles in the eye and the muscle of upper eyelid.
  
• The visceral motor component controls parasympathetic innervation ( nerves related to involuntary actions ) of the ciliary muscles and constrictor papillae.
  

Functions of oculomotor nerve:

1. Controls movements of the eyeball.
   
2. Raises upper eyelid.
   
3. Constrict pupils reducing light entering the eye.
   
4. Accommodation or adaptation to short range vision.