Proteins

Question 1

Classes of amino acids

Answer 1

Aliphatic (usually linear, hydrocarbon R groups)
Aromatic
Sulphur containing
Basic (+ve charge)
Acidic (-ve charge)
Uncharged polar (hydrophilic)
Other

Question 2

Primary stucture

Answer 2

Sequence of amino acids in a polypeptide chain

Question 3

Secondary structure

Answer 3

Spatial arrangement of amino acids that are near each other in the linear sequence
Alpha helix, beta-pleated sheet

Question 4

Tertiary structure

Answer 4

Spatial arrangement of amino acid sequences that are far apart in a linear sequence (weak interactions)

Question 5

Quaternary structure

Answer 5

Spatial arrangement of individual polypeptide chains in a multisubunit protein

Question 6

Cooperativity

Answer 6

Binding at one site on the protein alters affinity at the other points

Question 7

Globular proteins

Answer 7

Varied functions =>
Enzymes
Messengers (hormones)
Stock of amino acid
Transporters
Structural function (eg. actin and tubulin)

Question 8

Fibrous proteins

Answer 8

Structural functions =>
Bone matrices
Muscle fibre
Tendons
Connective tissue