proteins

Question 1

what is a dipeptide?

Answer 1

a molecule of two amino acids

Question 2

what is a polypeptide?

Answer 2

a molecule of more than two amino acids

Question 3

what is a protein?

Answer 3

one or more polypeptides joined together

Question 4

what are proteins made from?

Answer 4

hydrogen, carbon, oxygen and NITROGEN

Question 5

when polypeptides are formed, what is released?

Answer 5

a molecule of water

Question 6

what is the primary structure of a protein?

Answer 6

sequence of amino acids

Question 7

what is the secondary structure of a protein?

Answer 7

hydrogen bonds forming between amino acids, making an alpha helix or beta pleated sheet

Question 8

what is the tertiary structure of a protein?

Answer 8

more bonds form, chain is coiled/folded further and it’s the final 3d structure for a single polypeptide chain

Question 9

what is the quaternary structure of a protein?

Answer 9

the way polypeptide chains are assembled together

Question 10

name different proteins and their function

Answer 10

enzyme - metabolism
structural proteins
transport proteins
antibodies - immune response

Question 11

describe the biuret test for proteins

Answer 11

add a few drops of sodium hydroxide solution
add copper sulphate solution
positive result: purple colour