2.3.5 - Levels Of Protein Structure

Question 1

Describe The Primary Structure Of A Protein
(2 Points)

Answer 1

~ Sequence of amino acids bonded by covalent peptide bonds.

~ Is specific for each protein.

Question 2

What Determines The Primary Structure Of A Protein?

Answer 2

The DNA of the cell.

Question 3

How Does The DNA Of The Cell Determine The Primary Structure Of A Protein?

Answer 3

Instructs the cell to add certain amino acids in specific quantities in a certain sequence.

Question 4

Describe The Secondary Structure Of A Protein

Answer 4

Is the 2D arrangement of the chain of amino acids, either alpha helix or beta pleated sheets.

Question 5

How Does The Secondary Structure Of A Protein Occur?

Answer 5

When the weak negatively charged nitrogen and oxygen atoms interact with the weak positively charged hydrogen atoms to form hydrogen bonds.

Question 6

In The Secondary Structure, What Shapes Form As A Result Of Hydrogen Bonding?
(2 Points)

Answer 6

~ Alpha helix.

~ Beta pleated sheets.

Question 7

How Does The Alpha Helix Shape Occur?

Answer 7

When the hydrogen bonds form between every fourth peptide bond.

Question 8

How Does The Beta Pleated Sheet Occur?

Answer 8

When the protein folds so that 2 parts of the polypeptide are parallel to each other enabling hydrogen bonds to form between parallel peptide bonds.

Question 9

How Can Hydrogen Bonds Be Broken?
(2 Points)

Answer 9

~ High temperatures.

~ pH changes.

Question 10

Describe The Tertiary Structure Of A Protein
(2 Points)

Answer 10

~ 3D folding of the secondary structure into a complex shape.

~ Leads to additional bonds forming between the R groups.

Question 11

How Is The Shape Of The Tertiary Structure Determined?

Answer 11

By the type of bonding that is present.

Question 12

What Are The Additional Bonds In The Tertiary Structure?
(4 Points)

Answer 12

~ Hydrogen, between R groups.

~ Disulphide, between cysteine amino acids.

~ Ionic, between charged R groups.

~ Weak hydrophobic interactions, between non-polar R groups.

Question 13

Describe The Quaternary Structure Of A Protein

Answer 13

3D arrangement of more than one polypeptide.

Question 14

What Bonds Are Present In The Primary Structure Of A Protein?

Answer 14

Peptide.

Question 15

What Bonds Are Present In The Secondary Structure Of A Protein?
(2 Points)

Answer 15

~ Peptide.

~ Hydrogen, between the amino and carboxyl group.

Question 16

What Bonds Are Present In The Tertiary Structure Of A Protein?
(5 Points)

Answer 16

~ Peptide.

~ Hydrogen.

~ Disulphide.

~ Ionic.

~ Hydrophobic interactions.