Aqueous And Vitreous Humo

Question 1

Optically clear, slightly alkaline liquid that occupies the anteiror and posterior chambers of the eye

Answer 1

Aqueous humor

Question 2

What does aqueous humor have less of than blood plasma

Answer 2

Protein and glucose

Question 3

What does aqueous humor contain more of than blood plasma

Answer 3

Lactic acid and ascorbic acid

Question 4

What does the aqueous humor provide

Answer 4

Necessary metabolites, primarily oxygen and glucose, to the avascular cornea and lens.

Question 5

Where is aqueous humor produced

Answer 5

Pars plicata

Question 6

Where is the aqueous humor secreted

Answer 6

Posterior chamber through the epithelium covering the ciliary process

Question 7

What is the function of ascorbic acid

Answer 7

Reducing and antioxidant agent that functions in fighting bacterial infection, detoxifying reactions, and in the formation of collagen in fibrous tissue, teeth, bones, CT, skin, and caps

Question 8

What is aqueous humor filtered from

Answer 8

Blood

Question 9

What is the aqueous humor secreted from

Answer 9

The NPE of the ciliary processes

Question 10

Volume of aqueous

Answer 10

0.2 microliters

Question 11

How often is aqueous replaced

Answer 11

Every 100 minutes

Question 12

5 main components of the aqueous

Answer 12

1. Bicarbonate
2. Lactic acid
3. Ascorbic acid
4. Chlorides
5. Glucose

These are also found in blood plasma but in different concentrations

Question 13

Correlation between aqueous humor comp and attract formation

Answer 13

None

Question 14

The highly transparent and dilute solution of salts, soluble proteins and hyaluronic acid contained within a meshwork of the insoluble protein, collagen

Answer 14

Vitreous humor

Question 15

What is the makeup of vitreous

Answer 15

Salts
Soluble proteins
Hyaluronic acid
In collagen

Question 16

What percentage of vitreous is water

Answer 16

98.5% to 99.7%

Question 17

How is vitreous described

Answer 17

As having a CT status and being an extracellular matrix

Question 18

What are the most important vitreous humor metabolites?

Answer 18

Magnesium
Copper
Zinc
Selenium

Question 19

What is important about magnesium, copper, zinc, and selenium in vitreous humor?

Answer 19

They are in the vitamins for AREDS. AREDS 2 is more nutritionally based compared to AREDS 1. Can take theses with vitamin C supplement

Question 20

___________ has a significant role in the production and secretion of several CT macromolecules of the vitreous body

Answer 20

Nonpigmented epithelium of the pars plana

Question 21

Where is the collagen content the highest in the vitreous humor

Answer 21

In the base

Question 22

Where is the second place that the collagen content is the highest in the vitreous humor

Answer 22

Cortex

Question 23

Where is the collage lowest in the vitreous humor

Answer 23

Center

Question 24

Arrangement of collagen in the vitreous

Answer 24

Uniform, 8-16nm in diamter

Question 25

Viewing the collagen of the vitreous

Answer 25

Cannot be seen with a slit lamp, but the pattern of variations in their density and regularity can be seen

Question 26

Density of the Colleen fibril network in the vitreous

Answer 26

Differs throughout

Question 27

What are the 3 main types of collagen in the vitreous humor

Answer 27

Type II Type IX Type XI

Question 28

Which type of collegen is most predominant in vitreous

Answer 28

Type 2

Question 29

A fibril forming collagen that accounts for 60-75% of the collagen in vitreous

Answer 29

Type 2

Question 30

Has been estimated to represent up to 25% of the collagen in vitreous

Answer 30

IX

Question 31

Is a minor (10-25% of total collagen in vitreous) fibril forming collagen that co assembles with the type II collagen to form the core of the heterocyclic fibrils (least role)

Answer 31

Type XI

Question 32

Heterotypic

Answer 32

In the vitreous, nearly all of the collagen is in thin uniform, and heterotypic fibrils (mixed compositions)

Question 33

What are the non collagen components of vitreous

Answer 33

``` Fibrillin Opticin GAGs Hyaluronic acid Hyalocytes Fibroblasts ```

Question 34

Family of glycoproteins that form microfibrils with a characteristic beaded structure.

Answer 34

Fibrillin

Question 35

These represent the major structures component of the zonules

Answer 35

Fibrillin

Question 36

What is Marfan syndrome caused by

Answer 36

Mutations in fibrillin 1

Question 37

Glycoproteins that was initially IDed as the major component in a pool of macromolecules extracted from the surface of vitreous collagen fibrils.

Answer 37

Opticin

Question 38

This is a member of the family of extracellular matrix small leucine-rich repeat protein/proteoglycans

Answer 38

Opticin

Question 39

What does opticin do

Answer 39

Binds growth hormone and GAGs

Question 40

Composed of long chains of repeating units

Answer 40

GAGs

Question 41

All GAGs are attached to a protein core except what

Answer 41

Hyaluronic acid

Question 42

What is the order of eye structure from most to least GAGs

Answer 42

Vitreous Cornea Sclera

Question 43

The major vitreal component is a long unbranched molecule coiled into a twisted network

Answer 43

Hyaluronic acid

Question 44

This makes things gooey, causes things to be gelatinous. Loss of this liquify things

Answer 44

Hyaluronic acid

Question 45

This is a hydrophilic macromolecules located in specific sites within the collagen fibril network and is believed to maintain the wide spacing between fibrils

Answer 45

Hyaluronic acid

Question 46

Where is the the concentration of HA the highest?

Answer 46

Posteiror cortex

Question 47

Where is there the least HA

Answer 47

Center

Question 48

What is the gel structure of HA a result of

Answer 48

The interaction of collagen and HA

Question 49

What does HA do

Answer 49

Stabilizes the network formed by the collagen strands

Question 50

___ is the predominant GAG in mammalian vitreous

Answer 50

HA

Question 51

Composition of HA

Answer 51

Linear, polymetric GAG built from networks through entanglement!!

Question 52

How is HA distinguished from other GAGs

Answer 52

Not synthesized covalently, linked to a core porting, and it is never sulfated ******

Question 53

These are vitreous cells located in a single, widely spaced layer in the cortex near the vitreal surface and parallel to it

Answer 53

Hyalocytes

Question 54

Function of hyalocytes

Answer 54

Synthesize HA, synthesize glycoproteins for the collagen fibrils, phagocytized properties

Question 55

Appearance of hyalocytes in different parts of the vitreous

Answer 55

Vitreous base are fibroblast like when anterior to the ora serratta. Macrophage like when posteiror to the ora serrata

Question 56

Hyalocytes in the back of the eye

Answer 56

Eat more, work less (macrophage)

Question 57

Hyalocytes in the front of the eye

Answer 57

Work more, eat less. Fibroblasts like

Question 58

These synthesize the collagen fibrils that run anteroposteriorly and are active in pathologic conditions

Answer 58

Fibroblasts

Question 59

Functions of vitreous

Answer 59

- Physical support holding the retina - storage for metabolites - shock absorber - transmits and refracts light, aiding in focusing the rays on the retina

Question 60

How much more vitamin C does vitreous have than plasma

Answer 60

40x

Question 61

Vitreous floaters

Answer 61

When the surrounding HA and suspending collagen fibrils of the vitreous begin to degenerate, the collagen fibrils will begin to coalesce. When enough of this coalescing occurs, what was once too small to be detected by the retina, becomes evident. These small condensations of collagen, where the gel of the HA is missing and is replaced with a more liquid substrate, are called vitreous floaters