STRUCTURE AND FUNCTIONS OF CONNECTIVE TISSUE PROTEINS; COLLAGEN

Question 1

————- is a complex extracellular matrix

Answer 1

connective tissue

Question 2

what are functions of connective tissue ?

Answer 2

Provides support and connecting frame work for all other tissues.

Question 3

The ECM contains THREE major classes of biomolecules. What are they?

Answer 3

1.Structural proteins (Collagen, Elastin & Fibrillin.)
2.Specialized proteins (Fibronectin & Laminin.)
3.Proteoglycans.

Question 4

what are the major functions of extracellular matrix (ECM)

Answer 4

Protection, Structural support, Connection & binding, Storage, Transportation, Immune function.

Question 5

In human body connective tissue found in

Answer 5

skin, bone, tendons, cartilage, cornea, etc.

Question 6

connective tissue produced by ?

Answer 6

Fibroblasts, muscle cells & epithelial cells

Question 7

what is most abundant protein in human body?

Answer 7

Connective tissue

Question 8

what are types of collagens based on location and functions?

Answer 8

Fibril-forming, Network-forming, Fibril-associated.

Question 9

what type of structure does fibril-forming produces?

Answer 9

Rope-like structure.

Question 10

What will links collagen fibrils to other components in ECM?

Answer 10

Fibril-associated

Question 11

major types of collagen are how many are there and what are they?

Answer 11

4 types, type1, type2, type3, type4.

Question 12

Type I is liked with what in human body?

Answer 12

Bone (production in osteogenesis imperfecta.)

Question 13

Cartilage goes what type in collagen?

Answer 13

typeII

Question 14

Cartilage goes what type in collagen?

Answer 14

type II

Question 15

Reticulin -skin, blood vessels, uterus, fetal tissue, granulation tissue goes under what type in collagen?

Answer 15

Type III

Question 16

Type IV collagen found where in body

Answer 16

Basement membrane, basal lamina, lens.

Question 17

a polypeptide chain residues by how many amino acid and it is held together by ?

Answer 17

approximately 1000 amino acid and hydrogen and disulfide bond

Question 18

Three strands of polypeptide chains coiled around one another in a left-handed polyproline II helical conformation is what?

Answer 18

Triple helix

Question 19

How many types of chains are collagen is composed of and what are they?

Answer 19

2 types, alpha-1 & alpha-2.

Question 20

in type IV type of collagen what is responsible for secretion ?

Answer 20

Myofibroblasts.

Question 21

what does glycine residues do to structure of collagen?

Answer 21

allow the protein to coil more tightly, since they fit on the inside of the helix.

Question 22

what is super helical coil?

Answer 22

rope-like structure coiled together by 3 helices of collagen fiber.

Question 23

GLY (glycine) residue is there in which place in collagen?

Answer 23

Every 3rd amino acid is a GLY residue.

Question 24

what are X and Y amino acid in structure of collagen?

Answer 24

X is often proline or lysine ,
Y is often hydroxyproline (HPRO) or hydroxylysine (HLYS).

Question 25

In translation collagen is processed through ____________

Answer 25

secretory pathway.

Question 26

Fibroblasts lays down for _______________ chain fromation.

Answer 26

pre-pro-collagen α chain

Question 27

in translation polypeptides synthesizes by what and it's called as?

Answer 27

synthesized by ribosomes on Rough endoplasmic reticulum RER, and called and per-pro-collagen.

Question 28

how many types of synthesis of collagens are there in this ?

Answer 28

8

Question 29

X of amin acid, prolines and lysine's are hydroxylated to from

Answer 29

Y of amino acid, hydroxylysine and hydroxyproline

Question 30

the hydroxylation is performed by what?

Answer 30

prolyl and lysyl hydroxylase

Question 31

Function and product of hydroxylation are?

Answer 31

formation of stable triple helices. Pro-collagen (pro-α chain).

Question 32

what function in hydroxylation results in weak collagen chains?

Answer 32

Lack of lysyl hydroxylase

Question 33

if in body we have lack of ascorbic acid (vit C) what it causes and how it is affected to body?

Answer 33

causes scurvy, swollen gums, bruising, anemia, poor wound healing.

Question 34

For formation of stable triple helices. we required for___________.

Answer 34

Glycosylation

Question 35

In Glycosylation Hydroxylysine residues are covalently ENZYMATICALLY bound to what type of carbohydrate units.

Answer 35

glucose & galactose.

Question 36

how does Triple Helix structure forms?

Answer 36

By formation of disulfide bonds and hydrogen bonds between the three α-chains 

Question 37

Function and product of Triple Helix structure is?

Answer 37

fibril formation (fibrillogenesis). Procollagen (triple helix).

Question 38

Exocytosis of the collagen triple helix goes into the -------------- space.

Answer 38

extracellular

Question 39

Proteolytic Processing is Cleavage of the procollagen at what terminus.

Answer 39

C and N terminus

Question 40

Function and product of Exocytosis and Proteolytic Processing is?

Answer 40

 Collagen molecules become insoluble in water. Product is Tropocollagen

Question 41

what is the enzyme of Cross-Link Formation?

Answer 41

copper-dependent lysyl oxidase.

Question 42

Cross-Link Formation is essential for achieving for __________

Answer 42

tensile strength

Question 43

What are the function and product of Cross-Link of collagen synthesis?

Answer 43

subsequent fiber formation. collagen fibrils.

Question 44

Final product or end product of collagen synthesis is

Answer 44

collagen fiber

Question 45

how does fibers forms?

Answer 45

Several collagen fibrils accumulate to form a thick bundle called fibers.

Question 46

______________ is formed by cross-linking of hydroxylysine residues in adjacent tropocollagens. 

Answer 46

collagen fibrils

Question 47

Cross-linking of collagen increases with

Answer 47

increases with age

Question 48

Problems with cross-linking leads to

Answer 48

Menkes disease.

Question 49

Defects in any one of many steps in collagen fiber synthesis results in

Answer 49

genetic diseases

Question 50

Type I collagen disorder is also known as

Answer 50

brittle bone syndrome