Proteins

Question 1

What makes up an amino acid?

Answer 1

• NH2 = amine group
• COOH = carboxyl group
• R = side chain containing carbon

Question 2

What is a dipeptide bond?

Answer 2

bond between two amino acids

Question 3

What is a polypeptide bond?

Answer 3

bond between many amino acids

Question 4

What are the structures of a protein?

Answer 4

1. Primary
2. Secondary
3. Teritary
4. Quarternary

Question 5

What is the primary structure of a protein?

Answer 5

• the order and number of amino acids
• is the initial sequence so determines it’s function

Question 6

What is the secondary structure of a protein?

Answer 6

the shape that the chain of amino acid makes

Question 7

What are the types of secondary structures?

Answer 7

• alpha helix
• beta pleated sheet

Question 8

How does the secondary structure form?

Answer 8

• the hydrogen in a NH is slightly positively charged
• oxygen in C=O is slighly negatively charged
• results in weak hydrogen bonds which create alpha helix or beta pleated sheets

Question 9

What is the tertiary structure of a protein?

Answer 9

• the 3D shape of the protein
• formed by further twists

Question 10

What bonds maintain the tertiary structure?

Answer 10

• Hydrogen Bonds
• Ionic Bonds
• Disulfide Bridges

Question 11

Describe Disulfide Bridges in the tertiary structure.

Answer 11

• is bond between sulfur and R group in amino acid cysteine
• strong

Question 12

Describe Ionic Bonds in the tertiary structure.

Answer 12

• formed through bonds between carboxyl groups and amino groups (that aren’t involved in peptide chain)
• easily broken by pH

Question 13

Describe Hydrogen Bond in the tertiary structure.

Answer 13

• there’s lots of them
• easily broken

Question 14

What are globuar proteins?

Answer 14

• compact proteins
• example is enzymes

Question 15

What are fibrous proteins?

Answer 15

• long
• can form fibres
• examples is keratin