7.1 membrane fluidity

Question 1

what bonds hold the phospholipid bilayer together

Answer 1

hydrophobic interactions

-weaker than covalent bonds

Question 2

changing membrane

Answer 2

phospholidids move and drift

• somtimes they flipflop
• proteins move

Question 3

what keeps some membranes from freezing solid

Answer 3

unsaturated hydrocarbon tails and rich in phospholipids

- the unsaturated can’t pack as tightly as saturated because of the double bonds

Question 4

cholesterol affects membrane fluidity

Answer 4

high temp: retrains phospholipid movement

low temp: hinders close packing

Question 5

why don’t you want to solidify membrane

Answer 5

permeability changes

enzymes may inactivate