Proteins

Question 1

What is a protein

Answer 1

Macromolecule made of amino acid monomers
Structure allows to carry out specific function in particular contex

Question 2

What is an amino acid

Answer 2

Cominations of 3 nucleotides code for an amino acid

Question 3

What is the structure of an amino acid

Answer 3

Amino acids are chiral because of R group, except glycine (R=H)

Question 4

How are amino acids affect by pH

Answer 4

pH can give amino acid different charge

Question 5

What are the different classification of amino acids

Answer 5

1. Aliphatic
2. Aromatic
3. Sulfur-containing
4. Basic
5. Acidic
6. Polar
   (7. Miscellaneous)

Question 6

Describe Aliphatic amino acids

Answer 6

R group consists of hydrocarbon chain

Question 7

Descibre Aromatic amino acids

Answer 7

R group consists of hydrocarbon ring

Question 8

Describe Sulfur-containing amino acids

Answer 8

R group has sulfur, can create disulfide bridges with other sulfur-containing amino acids

Question 9

Describe basic amino acids

Answer 9

R group is basic

Question 10

Describe acidic amino acids

Answer 10

R groups are acidic

Question 11

Describe polar amino acids

Answer 11

R groups are polar

Question 12

What is a miscellaneous amino acid

Answer 12

R group does not fit in any of the other classification

Question 13

What different structures do proteins have

Answer 13

Primary, secondary, tertiary, quaternary

Question 14

Describe primary structure

Answer 14

Chain of amino acid monomers into polypeptide, joined via peptide bonds

Question 15

Describe secondary structure

Answer 15

3D arrangement of polypeptide chain
Hydrogen bonding between H of one amino acid and carboxyl oxygen of another in same chain
Can be alpha helix or beta pleated sheet

Question 16

Describe tertiary structure

Answer 16

Functional R groups of amino acids within chain interact with on another
Van der Waals, ionic, hydrogen, disulphide and
hydrophobic interactions

Question 17

Describe quaternary structure

Answer 17

Occurs when multiple polypeptides interact with one another, e.g. haemoglobin

Question 18

What is denaturation

Answer 18

When protein chemical bonds are interrupted/destroyed and secondary and tertiary structure is lost
Rarely results in loss of primary structure

Question 19

What functions do proteins have

Answer 19

THCRESSD
1. Structural
2. Enzymatic
3. Receptor
4. Hormonal
5. Transport
6. Storage
7. Defensive
8. Contractile

Question 19

What proteins have quaternary structure

Answer 19

1. Glycoproteins
2. Lipoproteins
3. Metalloproteins

Question 20

What are glycoproteins

Answer 20

Prortieins with one or more carbs covalently attached
Co-translational or post-translational modification

Question 21

What are the effects of Glycosylation

Answer 21

Gives proteins:
1. Stability
2. Solubility
3. Cell signalling
4. Orientation

Question 22

What are lipoprotetins

Answer 22

Proteins that combine with lipids
Found in cell membranes and transport hydrophobic molecules
(e.g. cholesterol transport in the blood)

Question 23

What are metalloproteins

Answer 23

Proteins with metal ions in their structures (co-factors)
Various functions (e.g. enzymatic, signal
transduction, storage and transport)

Question 24

What is the function of globular proteins

Answer 24

SETHS
1. Storage
2. Enzymes
3. Hormones
4. Transporters
5. Structural

Question 25

What is the function of fibrous proteins

Answer 25

Muscle fibres
Connective tissue

Question 26

What is the function of membranous proteins

Answer 26

Membrane transporters
Membrane enzymes
Cell adhesion molecules