1-5: Phospholipids + Macromolecular Assembly

Question 1

Enthalpy and Entropy

Answer 1

Question 2

Spontaneous vs Non- Spontaneous

Answer 2

Question 3

Phospholipid Assembly in Water is…

Answer 3

Question 4

Bilayer Stability

Answer 4

Question 5

The hydrophobic effect

Answer 5

Question 6

Semi-Permeable

Answer 6

Question 7

How do molecules move through the lipid bilayer?

Answer 7

When molecules move through the lipid bilayer, they:
* Move by diffusion
* Move WITH/ALONG the concentration gradient.
* Move in both directions.
* They do not stop moving at equilibrium

Question 8

Why do small molecules (nonpolar) permeate through the lipid bilayer?

Answer 8

Small, nonpolar molecules permeate because of hydrophobic interactions with the lipid bilayer.

Move from high to low concentration

Question 9

Permeability Scale

Answer 9

Question 10

Permeability Scale 2

Answer 10

Question 11

Answer 11

2, 3, 4, 1
Water is the smallest molecule - first
Toluene hydrophobic has a ring structure
Glycerol is hydrophilic with polar bonds and a linear structure
Phosphate is charged and an ion - last

Question 12

Passive Transport
Simple Diffusion
Facilitated Diffusion

Answer 12

Question 13

Channel Protein - Facilitated Diffusion

Answer 13

• Channel can be “open” or “gated”
• Molecules can diffuse through the channel.
• Usually selective for a specific type of molecule eg ions, small nonpolar molecules, small polar.
• The molecules do have to “interact” with the
  protein channel for the molecule to be transported.
• Provides a hydrophilic passageway i.e. aqueous pore.
• Transport through a channel usually occurs at a faster rate than carrier proteins.

Question 14

Carrier Proteins – Facilitated Diffusion

Answer 14

• Carrier proteins are “gated”.
• Transport a specific type of molecule i.e. more specific than channels.
• Open and closed formations.
• The protein undergoes a shape change (called conformational changes) to open and close the protein.