Chapter 6: Phospholipid Bilayers

Question 1

The _____ nature of phospholipids drives the organization of phospholipid bilayer

Answer 1

amphipathic

Question 2

Polar, hydrophilic _____ interact with water, while the nonpolar, hydrophobic _____ interact with each other and away from water

Answer 2

heads, tails

Question 3

In water, lipids spontaneously form micelles (fatty acids, fats, sterols), bilayers, or liposomes (phospholipids) mostly via _____ interactions

Answer 3

hydrophobic

Question 4

What is the Fluid-Mosaic Model?

Answer 4

the phospholipid bilayer of membranes is studded with membrane-spanning proteins

Question 5

What are peripheral membrane proteins?

Answer 5

associated with the membrane but does not pass through it

Question 6

What are integral membrane proteins?

Answer 6

passes through the phospholipid bilayer; aka transmembrane protein

Question 7

Phospholipid bilayers are _____ _____ to different substances

Answer 7

selectively permeable

Question 8

The _____ of phospholipid bilayers is affected by the _____ of phospholipid bilayers

Answer 8

permeability, fluidity

Question 9

Unsaturations/double bonds: create _____ in the fatty acid tails, which _____ the packing between phospholipids; _____ Fluidity and Bilayer _____

Answer 9

kinks, decreases, increase, permeability

Question 10

Increasing Fatty Acid Tail Length: more extensive _____ interactions that pack phospholipids together; _____ Fluidity and Bilayer permeability

Answer 10

hydrophobic, decrease

Question 11

Increasing temperature: increases _____; _____ fluidity and bilayer permeability

Answer 11

energy, increase

Question 12

_____ Fluidity = _____ Permeability

Answer 12

Increased, Increased
( therefore decreased, decreased)

Question 13

adding _____ molecules to artificial membranes dramatically _____ their permeability

Answer 13

cholesterol, reduces