Fibrous Proteins

Question 1

What is the most abundant fibrous protein in the human body?

Answer 1

Collagen

Question 2

What is collagen synthesized from?

Answer 2

fibroblasts, muscle cells, and epithelial cells

Question 3

What does type 1 collagen contain?

Answer 3

two α1 chains and 1 α2 chain

Question 4

What does type 2 collagen contain?

Answer 4

3 α1 chains

Question 5

Where is type 1 collagen found?

Answer 5

BONE, ECM loose cONNEctive tissue, te(O)N(E)dons, ski(O)N(E), cOrNEa

Question 6

Where is type 2 collagen found?

Answer 6

Cartilage, vitreous humor

Question 7

Where is type 3 collagen found?

Answer 7

Reticular fibers

Question 8

Where is type 4 collagen found?

Answer 8

Basement membrane or basal lamina

Question 9

What are the non-triple helical regions of collagen called?

Answer 9

noncollagenous domains

Question 10

What happens in Goodpasture’s syndrome?

Answer 10

Antibodies are developed against the α3 protein part of the NC1 domain, so immune system attacks the basement membrane of the glomeruli and the alveoli.

Question 11

Mutations in gene coding for type 4 collagen lead to what 2 diseases?

Answer 11

Alport and Goodpasture’s syndromes

Question 12

What amino acids is collagen rich in?

Answer 12

proline and glycine

Question 13

Every third amino acid residue in collagen is composed of what?

Answer 13

glycine

Question 14

Which type of OI is this: mildest form; blue sclera; dental abnormality; some hearing loss

Answer 14

Type 1

Question 15

Which type of OI is this: lethal bone deformity in utero or shortly after birth; blue sclera; dental abnormality; hearing loss unknown

Answer 15

Type 2

Question 16

Which type of OI is this: severe bone deformity; blue sclera; dental abnormality; high incidence of hearing loss

Answer 16

Type 3

Question 17

Which type of OI is this: moderate to severe bone deformity, no blue sclera or dental abnormalities

Answer 17

Types 4-7

Question 18

Where is elastin abundant?

Answer 18

lungs, walls of arteries, ligaments, skin

Question 19

What does Elastin lack?

Answer 19

a regular secondary structure

Question 20

Where is α1-antitrypsin synthesized?

Answer 20

mainly in the liver and also in monocytes and alveolar macrophages

Question 21

What does a mutation in the α1-antitrypsin result in?

Answer 21

substitution of lysine for glutamic acid

Question 22

What is the direction of dislocation in the lens in Marfans?

Answer 22

superio-temporal

Question 23

Which is inherited? Alport or Goodpasteur’s

Answer 23

Alport