Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
19 Cards in this Set
- Front
- Back
|
|
|
1. What do you call the tight junction that forms a zone or belt around the entire cell and joins it with each of the adjacent cells?
|
zonula occludens
|
|
In what type of intercellular junction are the plasma membranes separated by a narrow intercellular space that contains a specific glycoprotein cell adhesion molecule that contributes to cell stability and adhesion?
|
zonula adherens
|
|
What are the two names for the round button like intercellular junctions
|
macula occludens or macula adherens
|
|
A. What is the radius of curvature of the cornea? of sclera?
|
8mm=corneal radius of curvature
12mm=scleral radius of curvature |
|
B. When viewed from the front, what is the vertical corneal diameter? horizontal corneal diameter?
|
B. vertical corneal diamter=11mm
C. horizontal corneal diameter=12mm |
|
What is the central corneal thickness? peripheral corneal thickness?
|
central corneal thickness=0.53mm, peripheral corneal thickness=0.71mm
|
|
What do you call the fine ridges on the surface of corneal epithelial cells that enhance the stability of the tear film?
|
ridgelike projections-microplicae
fingerlike projections-microvilli |
|
What are the three types of cells that make up the corneal epithelium?
|
1) Surface cells
2) Wing Cells 3) Basal Cells |
|
What are the three types of cells that make up the corneal epithelium?
|
1) Surface Cells
2) Wing Cells 3) Basal Cells |
|
What is the posterior shape of corneal epithelial wing cells, posterior shape?
|
posterior concave, anterior convex
|
|
In what corneal layer does keratoconus first present?
|
usually central focal disruptions in the basement membrane and Bowman's layer, folds in the posterior stroma and Descemet's occur next
|
|
What is the thickness of the corneal epithelium in realtion to the other layers?
|
50 microns, 10% of total corneal thickness
|
|
What is the thickness of Bowman's membrane?
|
8-14 microns
|
|
What is the thickness of the corneal stroma in relation to the other corneal layers?
|
90% of entire corneal thickness, 470 microns
|
|
What are stromal lamellae made up of
|
coaxial bundles of collagen fibers that lie parallel to each other that extend the entire length of the cornea and are held in place by mucopolysaccharides and glycoproteins.
|
|
Would the orientation of the fibrils in picture c or d be an example of a transparent cornea?
|
picture c because the fibrils are equally spaced allowing for scattered light to be eliminated by destructive interference according to Maurice.
|
|
How many microns thick is each corneal lamellae?
|
2 microns
|
|
How thick is Descemet's membrane?
|
fetal Descemet's is approximately 5 microns but by age 40 Descemet's is up to 15 microns
|