Chapter 14- Ocular anatomy and physiology part 1 (2) Flashcards
What is the sclera?
The outer coat of the eye (the white of the eye).
What is the sclera composed of?
Dense irregular connective tissue containing collagen fibres.
The central one sixth is modified into what?
The transparent cornea
The corneoscleral junction is known as?
The limbus
What is the function of the cornea?
The cornea protects the eye and helps to focus incoming light on the retina.
The cornea is composed of 5 layers. What are they?
1- Epithelium 2- Bowman’s layer 3- Stroma 4- Descemet’s layer 5- Endothelium
What forms the bulk of the cornea?
The stroma
The corneal stroma is an example of what?
It is an example of dense regular connective tissue, as it is made up of tightly packed, and regularly arranged collagen.
What is the arrangement of collagen in the sclera and what does this cause?
The collagen in the sclera is irregular, and so this structure is opaque.
What is the outer corneal layer known as?
The corneal epithelium
What kind of epithelium is the corneal epithelium?
It is a stratified (multi-layered) squamous epithelium.
What is the function of the corneal epithelium?
It protects from dirt, eyelids.
What is simple epithelia ideal for?
For areas where the exchange of substances is required.
What is a good example of simple squamous epithelium?
The inner surface of the cornea, known as the corneal endothelium.
What is the function of the corneal endothelium?
It allows the avascular cornea to exchange substances with the aqueous.
Nutrients are transported up, waste is transported down.
