Connective tissue: collagen and the eye (akers)

Question 1

What are the 4 types of embryonic connective tissue?

Answer 1

Mesenchymal connective tissue (embryo and fetus)
Mucous connective tissue (umbilical cord)
Supporting connective tissue (cartilage and bone)
Hematopietic tissue (blood and bone marrow)

Question 2

What are formed and reside in the connective tissue; and are also called fixed cells.

Answer 2

Fibroblasts

Question 3

Some cells are not fixed and can travel within the tissue. Eosinophils, mast, and plasma cells (derived from B-lymohocytes are ___________.

Answer 3

Wandering cells

Question 4

Fibroblasts are the predominant cells in connective tissue, where they produce __________ and other components of the extracellular matrix.

Answer 4

Procollagen

Question 5

Briefly explain collagen structure.

Answer 5

Procollagen subunits make up a triplex helix collagen fibril and many collagen fibrils make up collagen fibers (collagen bundle)

Question 6

How many types of collagen are recognized in humans?

Answer 6

16 different types

Question 7

What type comprises 90% of all collagen in the body?

Answer 7

Type 1

Question 8

3 categories of collagen based on molecular structure

Answer 8

Fibrous collagens
non-fibrous collagens
filamentous collagens

Question 9

In the cornea is the tissue uniform or variable?

Answer 9

uniform, whereas the skin can vary greatly

Question 10

Non-fibrous collagens are mostly made up of _____ collagen and forms the non-fibrous _________________.

Answer 10

Type IV

Basement membranes

Question 11

Filamentous collagens can be subdivided into _________or _____________ which includes Types ___ ___ ___ ___.

Answer 11

Pericellular and matrix collagens

VI, VII, IX, X

Question 12

The fibers of the cornea are primarily composed of _____ collagen.

Answer 12

Type 1

Question 13

What protects the intraocular contents from injury and the function of the collagen in the _____ is structural.

Answer 13

Sclera

Question 14

Sclera contains predominantly Type ___ collagen and a small amount of Type __ collagen.

Answer 14

Type 1= 90%

Tyoe III=10%

Question 15

If you see sclerification in the eye collagen what 3 things are happening?

Answer 15

Not parallel
Not evenly spaced
Not uniform

Question 16

If sclera starts to change its strong structural integrity (starts to stretch) what could this lead to?

Answer 16

Myopia and glaucoma

Question 17

The central part of the ________ has a fine network of collagen fibers of 7-13 nm?

Answer 17

Vitreous

Question 18

The collagen is embedded in a hyaluronate gel and contributes to the maintenance of the ___________ acting as a shock absorber.

Answer 18

Intraocular pressure

Question 19

The lens is surrounded by a collagenous _________________.

Answer 19

Basement membrane

Question 20

This membrane is located under the corneal stroma and is usually referred to a as a basement membrane. What type of fibers does it consist of?

Answer 20

Descemet’s membrane

90% type 4 and 10% type V

Question 21

Retinal basement membrane: The delicate light-sensitive retina is supported by a structure known as ______________. What do retinal basement membranes mostly consist of?

Answer 21

Bruch’s membrane

Type IV collagen

Question 22

What type of collagen is a major component of the extracellular matrix of the human cornea. Has also been reported to be synthesized by corneal endothelial cells.

Answer 22

Type VI

Question 23

What type of collagenhas only been identified in vivo in descemet’s membrane.

Answer 23

Type VIII

Question 24

What collagen type in the vitrous contains about 3 times more than in cartilage.

Answer 24

Type IX

Question 25

When problems arise within the collagen of the cornea, a condition called _________ can arise. Where the weakened cornea bulges, reducing optical quality, and significantly reduces the visual acuity of the patient.

Answer 25

Keratoconus