L02: Membrane Physiology

Question 1

What is the resting membrane potential (RMP)?

Answer 1

The electrical gradient between the intracellular and extracellular compartments of the cell

Question 2

What are the roles of the cell membrane

Answer 2

• Define the boundaries of the cell
• Encloses the organelles and controls movement of substances in and out of the cell
• Creates and internal environment (where cell can thrive) that differs from the outside of the cell

Question 3

What is the main point of the arrangement of the phospholipid bilayer

Answer 3

impermeable to any particles that are hydrophilic

Question 4

What substances can pass through the lipid bilayer?

Answer 4

small, non polar, lipid soluble substances can diffuse directly through the bilayer

Question 5

What can’t pass directly through the membrane?

Answer 5

Water soluble, polar, large substances due to hydrophobic phospholipid tails (centre of bilayer=hydrophobic) => have to pass through membrane proteins

Question 6

What is compartment within the confines of the cell membrane

Answer 6

• Intracellular compartment
• Largely aqueous

Question 7

What do the structural features of the cell membrane allow for?

Answer 7

Creation of a perfect seal

Question 8

What is the compartment outside the confines of the cell membrane?

Answer 8

• Extracellular compartment
• Also called interstitium/ interstital space
• Largely aq environment