Fibrous Protein

Question 1

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

Answer 1

Collagen

Question 2

What is the typical amino acid sequence found in Collagen

Answer 2

Gly-Pro-Hyp

Question 3

Which part of the body is type I collagen found?

Answer 3

Skin
Bone
Tendon
Cornea

Question 4

Which part of the body is type II collagen found?

Answer 4

Cartilage
Intercalated disc

Question 5

Which part of the body is type III collagen found?

Answer 5

Blood vessel
Fetal skin

Question 6

Which part of the body is type III collagen found?

Answer 6

Blood vessel
Fetal skin

Question 7

Which part of the body is type IV collagen found?

Answer 7

Basement membrane

Question 8

Where is type VII collagen found?

Answer 8

Stratified squamous epithelium

Question 9

Where is type IX collagen found?

Answer 9

Cartilage

Question 10

Where is type XII collagen found?

Answer 10

Tendon
Ligaments
Other tissues

Question 11

The presence of which amino acid dictates that the helical conformation of alpha chain cannot be an alpha helix

Answer 11

Proline

Question 12

What is the initial polypeptide formed in the synthesis of collagen?

Answer 12

Procollagen

Question 13

Which type of collagen is found in highly extensible tissues

Answer 13

Type III

Question 14

Why does a lack of vitamin C cause scurvy

Answer 14

Because vitamin C is needed for the hydroxylation of specific proline and Lysine residues in collagen synthesis, hydroxylation of these residues enables collagen to have more hydrogen bonds hence strengthening the tripple helix structure of collagen

Lack of these hydoroxy residues leads to weak collagen structure hence weak bones and other symptoms

Question 15

Which hydroxylases, hydroxlyse the lysyl and prolyl residues of the Procollagen

Answer 15

Lysyl hydroxylase and prolyl hydroxylase

Question 16

Which stage of collagen synthesis requires vitamin C?

Answer 16

Hydroxylation stage

Question 17

Which stage of collagen synthesis involves the cleavage of disulfide-rich terminal regions of procollagen?

Answer 17

The terminal cleavage

Question 18

What is formed after the procollagen is cleaved of the disulfide-rich terminal regions?

Answer 18

Tropocollagen

Question 19

Which enzyme catalyzes the deamination of lysine residues to form allysine residues in Elastin and Collagen?

Answer 19

Lysyl oxidase

Question 20

Which syndrome is also known as brittle bone disease?

Answer 20

Osteogenesis imperfecta

Question 21

What causes osteogenesis imperfecta?

Answer 21

Mutation in the genes that code for alpha 1 or alpha 2 for type I collagen

Question 22

Which collagen defect causes Osteogenesis Imperfecta

Answer 22

Type I Collagen defect

Question 23

Which specific mutation in the alpha 1 or alpha 2 genes usually causes Osteogenesis imperfecta, and why

Answer 23

Mutation which causes the replacement of glycine with amino acids with bulky side chains
This hinders the formation of the triple helix structure

Question 24

What is dentinogenesis imperfecta?

Answer 24

A genetic disorder that affects tooth development

Question 25

What are the major causes of Elhers-Danlos Syndrome

Answer 25

deficiency of collagen-processing enzymes or from mutations in the amino acid sequences of collagen types I, III, or V.

Question 26

What are the two forms of Elhers-Danlos Syndrome

Answer 26

Classic Form Vascular Form

Question 27

What is the classic form of the Elhers-Danlos Syndrome and what is the cause

Answer 27

is characterized by skin extensibility and fragility and joint hypermobility, and is caused by a defects in type V collagen,

Question 28

What is the cause of the vascular form of Elhers Danlos Syndrome

Answer 28

Defect in type III collagen

Question 29

Which form of Ehlers Danlos Syndrome is the most severe

Answer 29

The vascular form which causes arterial ruptures

Question 30

Which type of osteogenesis imperfecta is severe and is lethal in the perinatal period?

Answer 30

Type II

Question 31

In which type of syndrome do we have the basement membrane being affected?

Answer 31

Alport syndrome

Question 32

Elastin is rich in which two amino acids?

Answer 32

Proline Lysine

Question 33

Collagen is rich in which two amino acids?

Answer 33

Proline and hydroxyproline

Question 34

In the extracellular space, what acts as the scaffold for tropoelastin deposition ?

Answer 34

Fibrillin

Question 35

Which amino acid is responsible for cross linking in both collagen and elastin?

Answer 35

Lysine

Question 36

The link formed between the allysyl side chains of tropoelastin polypeptides is called

Answer 36

Desmosine cross-link

Question 37

What changes tropoelastin to Elastin

Answer 37

When the desmosine cross-link is formed

Question 38

A mutation in what protein causes Marfan Syndrome

Answer 38

Fibrillin 1

Question 39

What is the precursor for elastin synthesis?

Answer 39

Tropoelastin

Question 40

Which enzyme cleaves the N and C terminals of procollagen molecules?

Answer 40

Procollagen peptidases

Question 41

Which fibrous protein can be used for skin care?

Answer 41

Elastin

Question 42

What inhibits elastase

Answer 42

alpha1-antitrypsin

Question 43

Mutation in what protein is responsible for Marfan Syndrome

Answer 43

Fibrillin-1

Question 44

What does a defiency in α1-antitrypsin lead to

Answer 44

it leads to unopposed elastase activity leading to emphysema

Question 45

The mutation of which gene results in defective fibrillin?

Answer 45

FBN1

Question 46

What is pectus carinatum

Answer 46

A disorder in which the breastbone is protruded outward

Question 47

What is pectus excavatum ?

Answer 47

A disorder where the breastbone is sunk into the chest

Question 48

Ectopia lentis

Answer 48

The subluxation of the lens of the eye

Question 49

Arachnodactyly

Answer 49

Long, tapering fingers and toes