Final answer:
The conjunctival fornix is divided medially by the medial rectus extraocular muscle.
Step-by-step explanation:
The conjunctival fornix is the junction between the superior and inferior conjunctival surfaces. It is divided medially by the medial rectus extraocular muscle. The medial rectus muscle is responsible for adduction of the eye, which means it moves the eye inward towards the nose. This muscle plays a role in controlling eye movements and helps us focus on objects that are close to us.