Lecture 13: intro to membranes/ membrane lipids

Question 1

basis of nervous system and contractile tissue function

Answer 1

membrane electrical properties

Question 2

what is the primary site of action of many hormones and can be primary site of drug action?

Answer 2

membranes

Question 3

protein secretion and intracellular membrane protein trafficking occur through _____

Answer 3

membrane fusion

Question 4

protein trafficking

Answer 4

moving proteins between different organelles within the cell or inside to outside the cell

Question 5

integral vs peripheral membrane proteins

Answer 5

• integral = extends from one end to another

- peripheral = don’t poke to the other side

Question 6

lipid

Answer 6

any substance soluble in a nonpolar substance while being essentially insoluble in water

Question 7

fatty acid structure favors the ___ configuration

Answer 7

trans

Question 8

more fluid means what for mp?

Answer 8

lower mp

Question 9

longer fatty acid tail means what for mp?

Answer 9

higher mp

Question 10

as # of double bonds inc. the Tm will ____

Answer 10

decreases because fewer VDW interactions

Question 11

structure of glycerophospholipid

Answer 11

• polar head group added via phosphodiester bond
• glycerol [core]
• hydrophobic tails

Question 12

the hydrophilic head (can/ cannot) H-bond

Answer 12

can H-bond with water

Question 13

glycerophospholipids are (more/ less) polar than fatty acids

Answer 13

more polar!

Question 14

differences between sphingolipids and glycerophospolipids

Answer 14

• no ester bond, already has a long tail
• amide group (NH2)
• [N-C] amide linkage NOT an ester bond
• can still attach a polar head group with a phosphodiester bond
• general structure is the same but attachment is different [no ester bonds!]

Question 15

headgroups added are ____ chains; (do/ do not) contain phosohate

Answer 15

saccharide chains; do not contain phosphate

Question 16

complex vs simple saccharide chains

Answer 16

• complex = gangliosides

- simple = cerebrosides

Question 17

structure of cholesterol

Answer 17

entirely nonpolar BUT still amphipathic because of -OH group on the end

Question 18

3 stabilizations of self-assembled monomers

Answer 18

• interactions between polar headgroups and solvent
• VDW interactions between hydrophobic tails
• increased solvent entropy [HYDROPHOBIC EFFECT]

Question 19

micelles are made of ____

Answer 19

single chain lipids