Polypeptides

Question 1

Polypeptides

Answer 1

short chains of amino acids linked by peptide bonds

Question 2

Extracellular matrix

Answer 2

non-cellular 3D macromolecule network

Question 3

List the functions of extracellular matrix

Answer 3

1. forming an essential support structure for cells
2. controlling communication between cells
3. segregating tissues
4. regulating cell processes such as growth, migration, and differentation

Question 4

List the general properties of ECM

Answer 4

1. scaffolding
2. rigid
3. dense
4. porous
5. insoluble
6. reservoir for growth factors and bioactive molecules

Question 5

ECM plays significant role in _________________ and __________

Answer 5

cellular communication and function

Question 6

General properties of ECM

Answer 6

1. biodegradable
2. biocompatible
3. determines and controls behaviors of cells: proliferation, adhesion, migration, polarity, differentiation, and apoptosis

Question 7

What are the 3 medical applications with the ECM?

Answer 7

1. tissue repair
2. organ transplantation
3. regeneration

Question 8

the ______________ step is key to improve mechanical properties after decellularization

Answer 8

cross-linking

Question 9

Collagen is the most abundant __________ of ________ origin.

Answer 9

protein of animal origin

Question 10

Collagen is the main structural protein found in ___________ tissue.

Answer 10

connective tissue; ligaments, tendons, and cartilage

Question 11

Collagen provides the skin with _________ and _________

Answer 11

support and strength

Question 12

Collagen forms the structural network of tissues such as ___________ (3)

Answer 12

blood vessels, bones, and cartilages

Question 13

Tropocollagen contains

Answer 13

3 polypeptide chains wound around each other to form a single helical structure

Question 14

Tropocollagen is stabilized with _______ bonding

Answer 14

hydrogen bonding

Question 15

List the biomedical applications of collagen

Answer 15

1. drug delivery
2. ophthalmology - collagen shield
3. sponges for burns/wounds
4. gene delivery - nanoparticles
5. hemostatic sealant

Question 16

Easy modification to produce desired materials is possible by using collagens __________ groups

Answer 16

functional

Question 17

the ____________ of amino acids of collagen allow many different chemical reactions

Answer 17

side chains

Question 18

_________ has a strong impact on the structure of collagen

Answer 18

drying

Question 19

__________________ hydrolysis forms gelatin

Answer 19

heat-induced

Question 20

Collagen can be altered to form _____________ (4)

Answer 20

1. films
2. gels
3. powders
4. sponges

Question 21

Keratin is a major component of ________ (4)

Answer 21

1. hair
2. feathers
3. wool
4. horns

Question 22

Keratin is a ______________ structural protein made of amino acids that form a ______________ structure

Answer 22

fibrous structural protein; repeating structure

Question 23

Keratin primarily _______ (5)

Answer 23

1. carbon
2. oxygen
3. nitrogen
4. hydrogen
5. sulfur

Question 24

Keratin protects __________ cells and strengthens certain organs

Answer 24

epithelial cells

Question 25

Keratin plays a key role in ____________.

Answer 25

wound healing

Question 26

Keratin is the most abundant __________________

Answer 26

structural protein

Question 27

List the general properties of keratin

Answer 27

1. biodegradable 2. biocompatible 3. insoluble in water 4. chelation 5. high stability 6. absorbs formaldehyde 7. high toughness 8. high modulus

Question 28

List the 5 biomedical applications of keratin

Answer 28

1. water purification and air cleansing 2. wound healing 3. bone regeneration 4. hemostasis 5. nerve repair

Question 29

what is silk fibroin and what is it composed of?

Answer 29

a fibrous protein made of 17 amino acids

Question 30

Where does silk fibroin come from?

Answer 30

1. cocoon silk from silkworm 2. spiders

Question 31

Silk fibroin is a _________ copolymer with ______________ and ___________ blocks

Answer 31

peptide copolymer hydrophobic and hydrophilic blocks

Question 32

the hydrophobic blocks with short amino acids form _____________ through ____________ bonding.

Answer 32

crystals through H bonding

Question 33

Hydrophilic blocks are also with ___________ amino acids

Answer 33

charged

Question 34

What are the 7 general properties of silk fibroin?

Answer 34

1. durability 2. biocompatible 3. lightweight 4. high strength 5. high toughness 6. elastic 7. stable under thermal conditions up to 250 C

Question 35

Solvent processed silk tends to ________________ than aqueous based

Answer 35

degrade slower

Question 36

If you regulate crystallinity of silk, you can alter ____________ (4)

Answer 36

1. degradation rate 2. pore size 3. porosity 4. MWD

Question 37

List the 4 processes for silkworm

Answer 37

1. gas forming - develop scaffolds 2. salt leaching 3. electrospinning 4. electro sprayings

Question 38

What is the limit to processing silk?

Answer 38

very difficult to produce in large quantities