CT 4

Question 1

Procollagen molecules are packaged and secreted by passing through the —

Answer 1

Procollagen molecules are packaged and secreted by passing through the Golgi.

Question 2

Procollagen peptidases cleave the N- and C- terminal of

Answer 2

collagens (Types, I, II, III)

Question 3

tropocollagen

Answer 3

cleaved product after procollagen

Question 4

topocollagen

Answer 4

entire (Gly-X-Y]n region and telopeptides

Question 5

deficiency in procollagen peptidases

Answer 5

Ehlers-Danlos Syndrome Type VII

Question 6

Hyperextensible skin that bruises easily

Answer 6

Ehlers-Danlos Syndrome Type VII

Question 7

Ehlers-Danlos Syndrome Type VII

Answer 7

Dislocation of major joints

Question 8

1/4 stagger for fibril formation with 400 Å gaps between head and tail

Answer 8

tropocollagen

Question 9

the site of cross-link formation i.e. where insolubilization takes place • nucleation site for calcium deposition in bone

Answer 9

Gaps of fibrils

Question 10

The structure repeats every — rows.

Answer 10

5

Question 11

Once the molecules are aligned, they are strengthened by —— cross-linking.

Answer 11

Once the molecules are aligned, they are strengthened by covalent cross-linking.

Question 12

step 1 ;lysyl oxidases

Answer 12

Oxidation of lysyl (and hydroxylysyl) residues

Question 13

step 2; Spontaneous condensations

Answer 13

of products of lysyl oxidase reactions form covalent bonds

Question 14

from step 2; formation of these —– bonds between amino acids located on ——- tropocollagen molecules forms a strong fiber.

Answer 14

formation of these covalent bonds between amino acids located on adjacent tropocollagen molecules forms a strong fiber.

Question 15

amino termini of lysyl residues are converted to ——-

Answer 15

amino termini of lysyl residues are converted to aldehydes.

Question 16

need O2 and Cu

Answer 16

lysyl oxidase

Question 17

aldol cross link

Answer 17

spontaneuous(alfter adehydes are made)

Question 18

lysinornorluecine crosslink from

Answer 18

aldehyde and NH3+

Question 19

lysyl oxidase crosslink

Answer 19

are spontaneous

Question 20

lysyl amino oxidase

Answer 20

can yield one or two aldehydes

Question 21

2 aldehydes goes thru aldol condensation

Answer 21

to make aldol

Question 22

link between one aldehyde and Amino group is

Answer 22

lysinonurleucine

(cross link in collagen or elastin)

Question 23

❂ Hydroxypyridinium

Answer 23

cross-linking of two hydroxylysyl residues and a lysyl residue

Question 24

Hydroxypyridinium

Answer 24

in collagen

Question 25

❂ Elastin is synthesized by the cell as a monomer called —-

Answer 25

❂ Elastin is synthesized by the cell as a monomer called tropoelastin

Question 26

Monomers of tropoelastin are covalently—— to one another renders the elastin fiber highly ——

Answer 26

Monomers of tropoelastin are covalently cross link

to one another renders the elastin fiber highly insol.

Question 27

tf as tropoelastin is released they are secreted and bind to microfibrils

Answer 27

T

Question 28

lysyl oxidase).

Answer 28

stimulates Cross-link formation in tropoelastin

Question 29

The ε amino termini of lysyl residues in elastin are converted to ——

Answer 29

The ε amino termini of lysyl residues in elastin are converted to aldehydes

Question 30

after aldehyds are made in tropoelastin

Answer 30

aldol crosslinks occur and is a spontaneuous rxn

Question 31

Desmosine crosslink

Answer 31

3 out of 4 nh2 groups converted to aldehydes

and then desmosine cross link forms

Question 32

1st step of collagen fibril formation

Answer 32

pro alpha chain made with OH on pro and Lys

Question 33

glycosylation

Answer 33

addition of N linked oligoscch to hydroxylation residues

occurs after pro alpha chains made and Prolines and Lysine hydroxylated

Question 34

3 pro alpha chain self assemble thru

Answer 34

disulfide bonds

Question 35

after self assembly of 3 pro alpha chain

Answer 35

procollagen forms triple helix

and is secreted thru exocytosis

Question 36

N and C propeptides removed

Answer 36

from procollagen molecule

Question 37

N and C propeptides removed

Answer 37

prompts formation of collagen fibril

Question 38

collagen fibrils form

Answer 38

collagen fiber

Question 39

cov cross link

Answer 39

helps form cov. cross link

Question 40

formation of collagen fibers

Answer 40

mediated by lysyl oxidase

Question 41

tropocollagen

Answer 41

allignment into fibrils

Question 42

gly mutation

Answer 42

trimer disruption (collagen)

Question 43

tf collagen cant be secreted to cytoplasm

Answer 43

F

can but will be either degraded in cyt or excreted as abnomal fibrils

Question 44

❂ Collagenases

Answer 44

matrix metalloproteinases (MMPs)

Question 45

cleave triple helical region of collagens.

Answer 45

collegenase action

Question 46

Vertebrate collagenases are critical to tissue——- e.g. uterus after pregnancy

Answer 46

Vertebrate collagenases are critical to tissue remodeling e.g. uterus after pregnancy

Question 47

cleave collagen at >200 sites

Answer 47

Bacterial collagenases

Question 48

Vertebrate collagenases

Answer 48

approximately 1/4 from the carboxy terminus