A transparent mucous membrane covering the exposed surface of the eyeball and inner surface of the eyelids; serves to protect the eyeball and keep it moist. Described in terms of three structural areas:

  1. the palpebral conjunctiva, which lines the inner surface of the eyelid and is further divided into the marginal, tarsal, and orbital conjunctiva;
  2. the bulbar conjunctiva, which covers the anterior eyeball, except for the cornea, and is further divided into the scleral and limbal conjunctiva; and
  3. the fornix, which represents the junction between the palpebral and bulbar conjunctivae.