1.6 Proteins

Question 1

What are proteins made up of

Answer 1

Amino acids

Question 2

Describe the structure of an amino acid (like the groups in the amino acid)

Answer 2

*Amine group (NH2) on the left
* Carboxyl group on the right (C=OOH)
* R group/ variable group at the top
and a C and a H below the carbon

Question 3

Describe how amino acids are joined together to form a dipeptide

Answer 3

• Condensation reaction
• Water is removed
• Peptide bond forms between OH of carboxyl and H of the Amine group

Question 4

What is the name of the bond between the amine group and the carboxyl group

Answer 4

Peptide bond

Question 5

What are proteins

Answer 5

Polymers made up of the monomer amino acids

Question 6

What are the 4 different level of structure in a protein

Answer 6

Primary
Seconday
Teritiary
Quarternary

Question 7

What is the primary structure is

Answer 7

The sequence of amino acids in a polypeptide chain

Question 8

What is the secondary structure

Answer 8

The sequence of amino acids that causes a part of a protein molecule to bend either into an Alpha helix or fold into Beta pleated sheets

Question 9

What are the secondary structures held together by

Answer 9

Hydrogen bonds hold them together

Question 10

Where do the Hydrogen Bonds form in the secondary structure

Answer 10

Between the C=O group of the Carboxyl group of one amino acid and the H in the Amine group of another amino acid

Question 11

What is the tertiary structure

Answer 11

*Protein gets further foldings of the secondary structure
*Forming a unique 3D shape
*Held in place by Ionic, Hydrogen and disulphide bonds

Question 12

Where do the ionic and Disuphide bonds form in the tertiary structure

Answer 12

Between the R groups of different amino acids

Question 13

When do you get disulphide bonds

Answer 13

If both amino acids have sulphur in their R groups

Question 14

What is the quarternary structure

Answer 14

A protein made up of more than one polypeptide chain

Question 15

What is an example of a quarternary structure protein

Answer 15

Haemoglobin

Question 16

What happens if a protein denatures

Answer 16

The bonds which hold the tertiary structure and secondary structure break and therefore their unique shape is lost

Question 17

What are the conditions that cause enzymes to denature

Answer 17

Too high a pH( too many H+ions or OH- ions)
Too high a temperature (too much kinetic energy)

Question 18

What is the importance of the primary structure

Answer 18

If even one amino acid in the sequence changes it will cause the Ionic, Hydrogen or disulphide bond to form at a diff location resulting in a diff 3D shape

Question 19

What is an example of different 3D shapes (in carrier proteins)

Answer 19

They will have a different shaped binding site