Autres

Question 1

Volume de tear par oeil

Answer 1

env 6ul/eye

Question 2

Turnover des tears

Answer 2

environ 1,2 ul/min

Question 3

Que permet de créer le Pentose phosphate pathway/Hexose monophosphate shunt

Answer 3

NADPH
35% du métabolisme du glucose a/n épithélium cornéen

Question 4

Major source of ATP in the epithelium cornea

Answer 4

Cycle de Krebs

Question 5

Quelles sont les 3 principales protéines dans le tear film?

Answer 5

Lysozyme
- Bacteriolytic agent

Lactoferrin
- Antimicrobial activity

Tear-specific prealbumin (TSP)
- Bactericidal activity
- Role in retinol transport in tear fluid

Small amounts of albumin, antiproteinases, glycoproteins and immunoglobulins

Question 6

Melting point des lipides dans le tear film?

Answer 6

35°

Question 7

2 layers de la cornée où la majorité du O2 est consumed for aerobic metabolism

Answer 7

Épithélium
Endothélium

Question 8

Major metabolic substate in corneal metabolism

Answer 8

Glucose

Question 9

Much of the energy produced in corneal metabolism is used for what?

Answer 9

Maintain corneal transparency
Main function is to maint a consistent water hydration of 78%
Does so through the continued maintenance of ions pumps (NA-K-ATPase, Cl-)

Question 10

2 major functions of the corneal endothelium

Answer 10

Principal mechanism of maintainin corneal hydratation and transparency

Provides a physical barrier controlling the entry of fluid and dissolved solutes into the stroma from the aqueous humour

Question 11

2 principaux composés de la lens

Answer 11

Water 66%
Protein 33% (higher comparativement à la plupart des tissus dans le corps)

Question 12

3 main groups of lenticular proteins (water soluble)

Answer 12

Alpha-crystallins (15%) : heaviest
Beta-crystallins (55%)
Gamma-crystallins (15%) : lightest

Question 13

What is the function of glutathione in the lens?

Answer 13

Acts as a H+ sink

Helps to maintain integrity of lens fibre membranes and pumping mechanisms (senile cataracts : loss of lens glutathione)

Acts as a detoxicant

Question 14

Common causes of cataract

Answer 14

Db
Galactosemia (déficit enzyme nécessaire au métabolisme du sucre galactose présent dans le lait)
Toxicity of reactive substances
Following surgery for uveitis

Question 15

Principal retinal carbohydrate metabolism

Answer 15

Glycolysis et Krebs cycle