lecture 18 - lipids and membranes part 2

Question 1

What are neutral lipids?

Answer 1

triglycerides, diglycerides, monoglycerides
glycerol + fatty acids with ester linkage
cholesterol esters
do not have amphipathic properties

Question 2

What are membrane lipids?

Answer 2

3 common types:
phospholipids
glycolipids
cholesterol
these molecules are amphipathic - non polar fatty acid/sphingosine and polar sugar/phosphate/alcohol
OH group on cholesterol polar, rest of molecule non-polar

Question 3

What is sphingomyelin?

Answer 3

a phospholipid containing sphingosine

Question 4

What are ceramides?

Answer 4

contain sphingosine with an amide-linked fatty acid

Question 5

What is cerebroside?

Answer 5

a glycolipid containing sphingosine

Question 6

What are gangliosides?

Answer 6

contain branched polysaccharide chains with up to seven sugars

Question 7

Describe how Phase Transitions in lipid bilayers take place

Answer 7

increase in temperature leads from solid gel-like consistency to fluid consistency
At constant temperature:
Increases in cholesterol or saturated fatty acid content make a membrane bilayer
more solid- or gel-like
Decreases in fatty acid chain length or increases in unsaturated fatty acid content
make a membrane bilayer more fluid-like