Biology -- Phospholipids

Front 1

selective permeability

Back 1

a membrane allows some substances to pass more easily than others

Front 2

main membrane material?

Back 2

phospholipids form into a bilayer

Front 3

amphipathic

Back 3

have both hydrophobic and hydrophillic regions --> phospholipid

Front 4

fluid mosaic model

Back 4

a membrane with a fluid structure w/ proteins embedded or attached to a double layer of phospholipids

Front 5

embedded proteins

Back 5

can move and they have often have hydrophobic and hydrophillic regions

Front 6

fluidity

Back 6

phospholipds move laterally very rapidly and often - it is very rare that they flip-flop

Front 7

fluidity and temp

Back 7

if temp. goes down too far, membrane get less solid which affects the function -- unsaturated phospholipids will remain more fluid at lower temp.

Front 8

cholesterol

Back 8

is wedged between phospholipids - at warmer temp. it restrains movement but at lower temp. keeps it

Front 9

peripheral proteins

Back 9

loosely bound to the surface of the embrane

Front 10

integral proteins

Back 10

penetrate the core of the bilayer, has a hydrophillic and hydrophobic (nonploar amino acids in alpha helices)

Front 11

role of membrane proteins

Back 11

reinforce shape of a cell and provide strong framework

Front 12

sidedness

Back 12

membrane has distinct inside and outside - lipid compositionmay be difft. therefore, when the membrane is synthesized(vesicles) the outside of the er/golgi will be the inside of the membrane