Amino Acids And DNA

Question 1

What part of the amino acid:

Accepts a proton
Donates a proton

Answer 1

The amino group

The carboxyl group

Question 2

Define amphoteric

Answer 2

Have acid and base properties

Question 3

Define zwitterion

Answer 3

A dipolar ion - containing both a positive and negative charge on the molecule

Question 4

When does a zwitterion exist?

Answer 4

Near an amino acids isoelectric point - the pH value when the overall charge of the amino acid is zero

Question 5

How do you make amino acids appear on chromatography paper?

Answer 5

Spray ninhydrin solution on plate, which is purple

Question 6

Equation for identifying amino acids using thin layer chromatography results and Rf data

Answer 6

Rf = distance travelled by spot
————————–
distance travelled by solvent

Question 7

Define protein

Answer 7

Sequence of amino acids joined by covalent peptide bonds

Question 8

What type of reaction is the formation of a peptide bond?

The break of a peptide bond? What are the conditions required for this reaction?

Answer 8

Condensation

Hydrolysis
6moldm-3 HCl + heat + 24 hours

Question 9

What is does the primary structure consist of?

How is a secondary structure formed?

How is a tertiary structure formed?

Answer 9

Sequence of amino acids that make a polypeptide chain

H bonds form within peptide links, causing chain to coil into an alpha helix or kink into a beta pleated sheet

More H, I, D bonds (intermolecular) form to produce more coils which produce a 3D shape

Question 10

Define residue

Answer 10

An amino acid which is part of a protein