Bio Test 2 Cell Membranes, Diffusion, Osmosis

Front 1

JD Robinson Unit Membrane hypothesis

Back 1

cell membranes like a sandwich,
esp phospholipid (fatty acid), heads, hydrophobic tails
----protein----
-----lipid-------
----protein----

wrong b/c proteins inside too, need to let water soluble things inside

Front 2

fluid-mosaic model

Back 2

- proteins disperesed, embedded in membrane/not
->components can be arrnaged in diff ways
-> fluid components can move, lipids move around

carbs on exterior of cell, attached to proteins and lipids

Front 3

peripheral proteins

Back 3

not embedded in membrane

Front 4

integral proteins

Back 4

embedded in membrane

Front 5

glycoprotein

Back 5

protein attached to carb

Front 6

glycolipid

Back 6

lipid attached to a carb

Front 7

unsaturated fatty acid -> ?

Back 7

increases fluidity of membrance b/c bending of hydroC chains

Front 8

cholesterol -> ?

Back 8

added to membrane (causes fatty acid change) can increase fluidity like unsat fat acid

Front 9

permeability

Back 9

unsat - high perm


sat - low perm

Front 10

movement of phospholipids

Back 10

move laterally (horiz) usually don't flip flop (transverse)

Front 11

ions/glucose

Back 11

can't get across membranes/phopholipid layer! how get across?

--> PROTEINS

Front 12

facilitated diffusion

Back 12

:how glucose moves in cells b/c can't get across membrane/phopho layer

:large [] to small []

:needs a way to move it, dependent on a free E gradient
:specific carrier: protein,

Front 13

active transport

Back 13

:carrying ions against free E gradient

:going from <er to LARGER []

:req's expend of E
uses ATP to carry one side membrane to other--> transport proteins
-----uniport----
-----simport----
-----antiport---

Front 14

transport proteins

Back 14

uniport- moves one solute in 1 direction, either in/out

simport - moves 2 diff mols same dir, either in/out

antiport - 2 diff mols 2 diff dirs

Front 15

active transport mechanism: sodium potassium pump

Back 15

found in all animal cells

integral membrane glycoprotein

inside nerve cell

energy used to move a solute against its concentration gradient

[Na] higher outside cell than [K], for each mol of ATP used, 2 K pumped into cell and 3 Na pumped out

1) 3 Na and 1 ATP molecule bind to protein pump
2) ADP released, ->ing change in pump's shsape
3) 3 Na released as 2 K bind to pump
4) Pi is released, 0>ing pump's shape to change releasing 2 K

breaks down 1 mol of ATP -> ADP and phosphate
---- uses the E released to bring 2 K ions into cell and export 3 Na ions

in cytoplasm, when nerves stimulated ->es increase in Na+ on one side, need to restore b/c impulse won't go

Front 16

diffusion

Back 16

net (loss/gain) movement of mols from regions high free E to regions LOW free E due to KE of the diffusion mols

Front 17

pure water -> ? in relation to free E

Back 17

pure water highest degree of order -> in contact w/ other water mols ->

> order = > free energy

Front 18

if + solutes to water -> ?

Back 18

->es more entropy (disorg) -> decrease free E

---->>> water w/ solutes less free E than pure H20

Front 19

osmosis

Back 19

diffusion of H20

: higher free E to lower free E

: osmosis across a cellular membrane, how things move in/out of cell if soluble

Front 20

water balance in living cells: isotonic

Back 20

relative to cell, free E of water same on either side of membrane

->es no net movement H20, wnat cells to be like this

Front 21

water balance in living cells: hypertonic (outside)

Back 21

cell will lose water to enviro,
: enviro = >er solute

--> free E of water less than inside of cell

--> animal cells: shriveled
--> plant cells plasmolyzed, less pressure

Front 22

water balance in living cells: hypotonic (outside)

Back 22

cell will gain water from external enviro

- cell has >er solute than external fluid

-> free E H20 less on side of cell than external

--> water goes in cell-> swells
ex: plants wilt, don't explode b/c cell wall

Front 23

cell's membrane plays active roll in the cells

Back 23

regulating metabolic activities, esp prokaryotic

Front 24

roles carb in cell membrane

Back 24

cell to cell recognition

name tags

Front 25

physiology and function of cell membrane depnds on ?

Back 25

proteins

Front 26

6 functions of cell membrane proteins

Back 26

enzymatic
transport
signal transduction
cell to cell recognition
intercellular joining
attachment to cytoskeleton and extracellular matrix ECM

Front 27

function of cell membrane protein: transport

Back 27

- spans membrane -> hydrophilic selective solute

- hydrolize ATP as E source, pump substances -> membranes

Front 28

function of cell membrane protein: enzymatic

Back 28

- active site exposed to substances in adj. solution

- sometimes org. as group carries out sequential steps of metabolic pathway

Front 29

function of cell membrane protein: signal transduction

Back 29

- binding site w/ specific shape -> specific chem messenger ex: hormone

- messenger (signal) -> shape change in proteins, sneds message inside cell

Front 30

function of cell membrane protein: intercellular joining

Back 30

- adjacent cells hooked together in diff junctoins

Front 31

function of cell membrane protein: cell to cell recognition

Back 31

- glycoproteins = ID tags recog'd by other cells
-carb attached to protein

Front 32

function of cell membrane protein: attachment to cytoskeleton and extracellular matrix (ECM)

Back 32

- proteins bound to cytoskel elements --> maint cell shape, fixes loca. some mem. proteins

- proteins bound to ECM -> coordinate extracellular/intra changes

Front 33

each molecule moves ___ but group mol's moves in a ___

Back 33

random
net

Front 34

diffusion requires E T?F

Back 34

false

Front 35

pure water

Back 35

highest degree of order, has greatest free E

Front 36

exocytosis

Back 36

cell getting rid of waste

Front 37

pinocytosis

Back 37

cell drinking