Which of the following does NOT produce mucin?

Mucin production in the eye primarily occurs in specific cell types, which play a vital role in maintaining the stability and function of the tear film. Goblet cells are well known for their secretion of mucin, a critical component of the tear film that helps to trap moisture and debris, enhancing the lubrication of the ocular surface.

Corneal squamous cells are involved in surface maintenance and can contribute to the mucin layer of the tear film as they produce certain glycoproteins that have mucin-like properties, aiding in the protection of the corneal surface.

Conjunctival squamous cells are also capable of producing mucins, contributing to the tear film's overall composition and ensuring a smooth surface for the cornea.

In contrast, conjunctival cuboidal cells primarily function in the secretion of aqueous and electrolytes rather than mucins. While they are important for tear film stability through other means, they do not directly produce mucins like the other cell types described. This distinct function of conjunctival cuboidal cells highlights the specialized roles different cells play in ocular surface health and tear film integrity.