B 1.2 Proteins

Question 1

DRAW AMINO ACID YAY

Answer 1

H
|
Amine Group – Alpha C – Carboxyl
|
R group

Question 2

Dipeptide Equation

(draw)

Answer 2

Amino Acid + Amino Acid = Dipeptide + Water

(condensation reaction)

Question 2

essential

Answer 2

cannot be synthesized => must obtain from food
vegan struggle :(

Question 3

non-essential

Answer 3

can be made from other amino acids

Question 4

polypeptides

Answer 4

infinite variety of possible amino acid combos
(hemoglobin, insulin, collagen)

Question 5

denaturation

Answer 5

caused by
too low or high temps
too low or high pH
irreversible
hydrogen bonds broken

Question 6

R group possibilities

Answer 6

hydrophilic / hydrophobic
⬇️
acidic / basic
polar / charged

Question 7

Primary Structure

Answer 7

peptide bonds (only)
R-group dictates bends
precise, predictable, repeatable

Question 8

Secondary Structure

Answer 8

regular hydrogen bonding (stable)
(between C:O and N-H)
- helix
- sheet

Question 9

Tertiary Structure

Answer 9

• ionic bonds - between charged R
• covalent bonds
• hydrogen bonds - between R
• hydrophilic & hydrophobic interactions of R
  pairs of cysteine (type of amino acid) form disulfide bridges (bonds)

Question 10

Quaternary Structure

Answer 10

CONJUGATED

Question 11

hydrophobic & hydrophilic interactions

Answer 11

hydrophobic core
hydrophilic outside

Question 12

Conjugated

Answer 12

quaternary structure + prosthetic group (non-polypeptide)

Question 13

Haemoglobin

Answer 13

globular & conjugated
- two alpha
- two beta
- four haem groups
function: carry oxygen within red blood cells

Question 14

non-conjugated

Answer 14

ONLY polypeptides

Question 15

Insulin

Answer 15

globular & non-conjugated
- two polypeptide chains
- two disulfide bridges
function: hormone that regulates blood glucose levels
- hydrophobic core, hydrophilic out
- soluble in water

Question 16

collagen

Answer 16

fibrous & non-conjugated
- three polypeptide chains
- triple helix structure
function: strength & structure in connective tissue: skin, cartilage, bones (TBs)
- repetitive sequence
- insoluble in water