Proteins Flashcards
1
Q
Describe the structure of amino acids
A
- Central C
- Carboxyl group (OH–C=O)
- H atom
- R group
- Amine group (H–N–H)
2
Q
What is the name given for a long chain of amino acids?
A
Polypeptides
3
Q
What bond forms between two amino acids?
A
Peptide bonds
4
Q
What is ‘primary structure’ in proteins?
A
A sequence of amino acids in a polypeptide
5
Q
What is ‘secondary structure’?
A
Shape polypeptide folds into:
-alpha helix
-beta pleated sheet
joined by hydrogen bonds
6
Q
What is ‘tertiary structure’?
A
- Secondary structure folded
- -Fibrous [long, thin and insoluble]
- -Globular [spherical, biochemical functions]
7
Q
What bonds do proteins with a tertiary structure contain?
A
- Hydrogen bonds (btwn R groups, not strong)
- Ionic bonds (btwn + and - amino acids, not strong)
- Disulfide bridges (amino acids with S in R group, strong covalent)
- Hydrophilic and Hydrophobic
8
Q
What is ‘quarternary structure’?
A
Protein made up from 2 or more polypeptide chain.
Held by same bonds as tertiary structure
9
Q
Describe a test for proteins
A
Biuret test
- Add KOH
- Add Copper sulphate
- Goes Mauve
