Flashcards in Exam 1 Remington- Cornea Deck (123)
What are the two functions of the cornea?
Transmission and Refraction
What is refraction of the cornea dependent on?
Curvatures, length, different indices
Anterior diameter of the cornea
12 mm horizontal, 11 mm vertical
Posterior diameter of the cornea
Horizontal and vertical diameters of 11.7 mm, sclera impinges inferiorly into cornea
Central thickness of the cornea
Peripheral thickness of the cornea
Anterior radius of curvature of the cornea
Posterior radius of curvature of the cornea
_____ radius of curvature means a steeper curve
What is regular astigmatism?
Principle meridians 90 degrees apart
What are 3 types of regular astigmatism?
WTR, ATR, and oblique
What is WTR astigmatism?
Vertical meridian is steepest (shortest radius of curvature) think football
What is ATR astigmatism?
Horizontal meridian is steepest
What is oblique astigmatism?
Steepest meridian at 45 or 135 degrees
What is irregular astigmatism?
Principle meridians are not 90 degrees apart
How is irregular astigmatism corrected?
What is the function of the plasma membrane lipid bilayer?
Controls molecular entrance and exit
What is the function of the cytoskeleton?
Structure and intercellular transport
What is the function of ribosomes?
What is the function of the endoplasmic reticulum?
What is the function of the Golgi apparatus?
3 types of cellular transport
Diffusion, facilitated diffusion, active transport
What do aquaporins do?
What type of channels are aquaporins?
Bidirectional in the cornea and lens
3 types of cell surfaces
Apical, lateral, and basal
What is a basal cell surface?
Sits on basement membrane, connective tissue
The basement membrane consists of what 2 types of lamina?
Basal and reticular
Basal lamina is secreted by what cell?
Reticular lamina secreted by what cell?