Chapter 3: 3.4 Tertiary and Quaternary Structure

Question 1

Define:

Tertiary Structure

Answer 1

A protein’s final folded state, results from interactions between amino acid side chains

Question 2

What interactions and bonds do tertiary structures involve? (5)

Answer 2

• Disulfide bonds
• Ionic bonds
• Hydrogen bonds
• Van der Waals forces
• Hydrophobic interactions

Question 3

What do secondary structures often organize into? Describe

Answer 3

Motifs
* A recognizable folding pattern involving two or more seconary structures and their connecting segments

Question 4

Define:

Quaternary Structure

Answer 4

Arragement of protein subunits into a complex

Question 5

What is each subunit of a quaternary structure?

Answer 5

Each subunit is an individual folded protein that generally have their own function

Question 6

True or False:

Each protein subunit in the quaternary structure is functional

Answer 6

Partially true, they are often only functional in the compelte structure

Question 7

True or False:

Quaternary structures are comprised of identical subunits

Answer 7

Not necessarily. They can be comprised of identical or different subunits

Question 8

What are quaternary structures with identical subunits known as?

Answer 8

Symmetrical proteins

Question 9

What are quaternary structures with different subunits known as?

Answer 9

Asymmetrical proteins

Question 10

How are quaternary structures referenced?

Answer 10

By the number of subunits
* Monomers have one subunit
* Dimers have two subunits
* Trimers have three subunits

Question 11

What can quaternary structures also be known as?

Answer 11

Multimers and oligomers