Proteins

Question 1

What are the monomers of proteins?

Answer 1

Amino acids

Question 2

What is a dipeptide?

Answer 2

Formed when 2 amino acids join together

Question 3

What is a polypeptide?

Answer 3

Formed when more than 2 amino acids join together

Question 4

What are proteins made up of in terms of polypeptides?

Answer 4

One or more polypeptides

Question 5

What is the general structure of an amino acid?

Answer 5

Carboxylate group

Amine group

R group

Question 6

How many amino acids are in the bank that all living things share?

Answer 6

20

Question 7

How are amino acids linked together?

Answer 7

Condensation reactions

Question 8

What is released during a condensation reaction?

Answer 8

Molecule of water

Question 9

What are the bonds that form between amino acids in condensation reactions?

Answer 9

Peptide bonds

Question 10

What reaction breaks down polypeptides and dipeptides?

Answer 10

Hydrolysis

Question 11

What is the primary structure of a protein?

Answer 11

Sequence of amino acids in the polypeptide chain

Question 12

What is the secondary structure of a protein?

Answer 12

Hydrogen bonds form between amino acids in chain

Makes them automatically coil into an alpha helix or fold into a beta pleated sheet

Question 13

What is the tertiary structure of a protein?

Answer 13

Coiled or folded further than in secondary

Bonds include hydrogen and ionic bonds

Disulfide bridges also form

Question 14

What is the quaternary structure of a protein?

Answer 14

Final 3D structure of a protein

Question 15

What test is used to test for proteins?

Answer 15

Biuret test

Question 16

What are the 2 stages in the biuret test?

Answer 16

Add sodium hydroxide solution to make the solution alkaline

Add some copper(II) sulfate solution

Question 17

What colour does the solution go if protein is present?

Answer 17

Purple

Question 18

What colour is the solution if protein is not present?

Answer 18

Blue