3. Proteins

Question 1

whats monomer involved in

proteins

Answer 1

amino acid

Question 2

describe the

structure of an amino acid

Answer 2

caboxyl group COOH
and a amine group NHH

Question 3

two amino acids makes

Answer 3

dipeptide

Question 4

3+ amino acids is a

Answer 4

polypeptide

Question 5

which elements make up proteins

Answer 5

C O H N S

Question 6

bonds,description

Primary proteins

Answer 6

• only peptide bonds between amino acids
• polypeptide chain of dif amino acids

Question 7

bonds,description

Secondary protein

Answer 7

1. alpha- coil
2. beta- pleated sheet
3. held in shape by additional H-bonds

Question 8

bonds,description

tertiary protein

Answer 8

coilded or folded chain is then folded or coiled again and more bonds are formed

1. ionic bonds between R groups (variable groups)
2. disulfide bond
3. hydrophobic and hydrohilic interactions when hydrophobic groups are close they clump together and hydrophilic groups are pushed outwards influencing overal structure
4. hydrogen bonds between slightly polar R groups

Question 9

bonds,description

Quaternary

Answer 9

made up of a differnet polypeptide chains held together

Question 10

what bonds hold amino acids together

Answer 10

peptide bond

Question 11

formation of peptide bond:

Answer 11

condensation

Question 12

breaking of a peptide bond:

Answer 12

hydrolysis

Question 13

x3 examples of globular proteins

Answer 13

1. insulin
2. amylase
3. haemoglobin

Question 14

x3 examples of fibrous proteins

Answer 14

1. collagen
2. keratin
3. elastin

Question 15

the structure and function

harmoglobin

Answer 15

• function: carry 02 around body
• structure: conjugated protein(aka has nonprotein group attached aka a prostetic group in this case haem wich has iron)
• globular

Question 16

the structure and function of

insulin

Answer 16

• function: regulate blood glucose level
• soluble so can travel in blood
• 2xpolypeptide chains bonded via disulfide bond

Question 17

the structure and function of

amylase

Answer 17

function: catalyses the breakdown of starch to maltose
structure: single chain both alpha helix and beta pleated
extracellular

Question 18

properties comparison between

globular and fibrous

Answer 18

globular
* soluble easily transported in fluids
* make up most enzymes

fibrous
* insoluble
* strong
* unreactive
* make up structural tissue

Question 19

properties and functions

Keratin

Answer 19

function: make up external structures in animals eg. hair nails horns
properties: flexible eg hair and hard eg nails

Question 20

properties and functions

collagen

Answer 20

function: animal connective tissue eg bone skin muscle
properties strong minerals can bind to increase rigidity

Question 21

roles of proteins

Answer 21

• immunological: all antibodies are proteins.
• signalling: many hormones and receptors are proteins
• catalytic: all enzymes are proteins, catalyzing many biochemical reactions
• structural: proteins are the main component of body tissues, such as muscle, skin, ligaments and hair

Question 22

Globular proteins

Answer 22

proteins form a spherical mass with a specific 3-D shape (tertiary and quaternary structure)
They fold up so that hydrophillic groups are on the outside and hydrophobic groups are inside the molecule

Question 23

explain the differnece between simple protein and a conjugated protein

Answer 23

conjugated:contain a non-protein group called a prostetic group
simple proteins dont

Question 24

describe the differneces in properties and functions of insulin a hormone and keratin present in hair and nails

Answer 24

insulin- globular protein, soluble, specific shape to bind to receptor, chemical messanger. Keratin fibrous protein, strong, insoluble, structural function

Question 25

describe why globular proteins are soluble in water but fibrous proteins are not