Bsci 330 Exam 2 Set 1

Front 1

formula for oxidation of glucose

Back 1

C6H12O6>6CO2+6H20

Front 2

what is the purpose of oxidation of glucose?

Back 2

-releases a lot of energy (-686 kcal per mole)
-this energy can be used to make atp

ADP + Pi> ATP
(+11.5 kcal per mole under cellular conditions)

Front 3

overall what happens in glycolysis?

Back 3

one molecule of glucose is converted to two molecules of pyruvate with the net production of 2 ATP and 2 NADH molecules

Front 4

what are the 3 phases of glycolysis?

Front 5

where does glycolysis occur?

Back 5

cytosol

Front 6

name 2 energy storage compounds?

Back 6

ATP and NADH

Front 7

how much ATP and NADH is created in glycolysis per molecule of glucose?

Back 7

-4ATP (2 is used up in the process)
-2 NADH

Front 8

How is a positive delta G made negative in glycolysis?

Back 8

low [product] due to constant removal
-reactions are coupled

Front 9

Is Oxygen needed in glycolysis?

Back 9

no

Front 10

draw the complete glycolysis pathway

Back 10

draw it: 110

Front 11

what would the free energy change graph of glycolysis look like?

Back 11

draw it

Front 12

What does fermentation do?

Back 12

uses NADH to reduce pyruvate, regenerates NAD+

Front 13

draw fermentation reaction for yeast

Back 13

draw it: 113

Front 14

draw the overall glycolysis reaction

Back 14

Glucose + 2ADP + 2Pi + 2NAD+ >2 pyruvate + 2NADH
+ 2ATP + 2H+ + 2H20

Front 15

when organisms have little or no O2, how do they get energy?

Back 15

glycolysis and fermentation

Front 16

membrane function: name and describe each

Back 16

Membrane Functions

Hint 16

membrane can select people to respond in earth

Front 17

Charles Overton

Back 17

1890
postulated the presence of a lipid coat on the cell surface
-reported that non-polar substances readily entered cells while polar substances did not

Hint 17

picture over a ton of lipids on the cell surface

Front 18

lipophillic

Back 18

non polar

Front 19

E gorter and F Grendel

Back 19

1925 used the Langmuir trough to conclude that the bilayer was 2 units thick.

fig 4.3 on 123

Hint 19

G and G are special agents that work for the CIA and have been using incarcaration techniques of seeing how close they can get people.

Front 20

describe what gorter and grendel concluded: give the entire process

Front 21

Hugh Davson and James Danielli

Back 21

recognized that a membrane could not be lipid only because this would not account for all materials crossing it

devised protein/lipid sandwich...hydrophilic proteins are present in one or more layers...on both sides of the lipid bilayer.

-

Hint 21

double D's in membrane

Front 22

determined lipid bilayer

Back 22

gorter and grendel
using langmuir trough

Front 23

determined that a lipid bilayer must have proteins embedded in it?

Back 23

davson and danielli

Hint 23

double d's in the membrane look like protein

Front 24

what is the davson-danielli model

Back 24

draw it
124

Front 25

Singer and Nicholson

Back 25

1972
proposed fluid-mosaic model of membrane

Hint 25

picture nick singing releasing a lot of fluid

Front 26

fluid mosaic model of membrane proposed by who?

Back 26

Singer and Nicholson

Hint 26

when u sing u bring up fluid and nick is useless except for fluid

Front 27

fluid mosaic model

Back 27

-present in fluid state (not so in previous structures)
-proteins are embedded discontinously in membrane (prvious structures did not have it this way)
-lipids can self assemble into liposomes and sheets

singer and nicholson proposed

Hint 27

sing though your lips, but nick sings through his ass because he never knows what he is talking about

Front 28

liposome

Back 28

sperical vesical composed of a lipid bilayer

Front 29

what can liposomes be used for?

Back 29

drug delivery

Front 30

common structure of biomembranes

Back 30

thin 6-8 nm double layer of lipid into which protein molecules are embedded

Front 31

biomembrans are held together by what?

Back 31

weak bonds-especially the hydrophobic effect that binds lipid tails together

Front 32

most lipids are free to move within the plane of the membrane...T/F

Back 32

true

Front 33

what are water soluble compounds

Back 33

polar or charged materials

Front 34

what does a lipid bilayer serve to do?

Back 34

-ipermeable barrier to water-soluble compounds

-lipids provide the flexibility, stability, and electrical resistance properties of membranes

Front 35

most abundandant type of membrane lipids?

Back 35

phospholipids (phosphoglyderides)....15-50percent of membrane

Front 36

what is the head group in phosphoglycerides?

Back 36

phosphate + polar group

Front 37

what are phosphoglycerides made of?

draw structure....pg126

Back 37

1)diacylglycerol
2)phospate
3) A polar group covalently linked to the phospate

head group, glycerol, and a fatty acid

Front 38

are the two fatty acid chains in phospolipids usually identical?

Back 38

no

Front 39

how many carbons does a fatty acid chain normally have?

Back 39

16-20

Front 40

what is saturation relating to lipids

Back 40

the number of double bonds

Front 41

what is a double bond in a fat

Back 41

unsaturated and normally the cis type

Front 42

what do double bonds do to lipids?

Back 42

creates a pronounced kink in the otherwise flexible tail because bonds are normally cis type

Front 43

fatty acids that lack double bonds

Back 43

saturated

Front 44

fatty acids possessing double bonds are

Back 44

unsaturated

Front 45

what can affect the packing of a lipid?

126

Back 45

chain length and saturation levels

Front 46

spingolipids

126

Back 46

sphingosine and a fatty acid R group....ceramide

Front 47

a ceramide

126

Back 47

sphingosine and a fatty acid R group

Front 48

sphingomyelin

Back 48

phosphoraled ceramide

2/27 in lecture notes

Front 49

cerebroside

Back 49

ceramide and a 6c sugar ring

Front 50

ganglioside

Back 50

ceramide and and 4 6c sugar rings

found in high concentrations in nervous system

Front 51

cholesterol

Back 51

4 rings attached to each other...lipid

Front 52

how rare or abundant is cholestoral?

Back 52

extremely abundant in some eukaryotic membranes, such as the plasma membrane of mammalian liver, 1:1 molar ratio with other phospolipids

Front 53

describe relationship between prokaryotic membranes and plant membranes relating to cholestoral

Back 53

cholestoral is absent from both plant and prokaryotic membranes

Front 54

two functions of cholestoral when in the membrane

Back 54

-increase the permeability barrier and modulate membrane fluidity

Front 55

integral membrane proteins

Back 55

-hydrophobic section of the protein is imbedded in the hydrophoic core of the lipid bilayer-held by hydrophobic effects

-often extend all the way through the lipid bilayer..transmembrane proteins

Front 56

peripheral membrane proteins

Back 56

-located outside lipid bilayer-held to polar surface of membrane by weak bonds

Front 57

lipid anchored proteins

Back 57

-located outside bilayer but are covalently bound to lipides that are part of the bilayer structure

Front 58

3 types of membrane proteins

Back 58

-integral membrane proteins
-peripheral membrane proteins
-lipid anchored proteins

Front 59

crystals of membrane proteins which retain their native conformation are what?

Back 59

difficult to obtain so only a relatively small umber of definitive tertiary structures are available via X-ray crystallography

because of this alternative methods were devised to look at structure of protein when embedded in membrane

Front 60

methods for studying integral membrane protein structure

Back 60

1)freeze fracture electron microscopy
2)extracting integral proteins from membranes using nonionic detergents
3)limited enzyme digestion to determine the sidedness of the protein
4)hydropathicity plots
5)spatial relatiohships between amino acid residues in the transmembrane domain using cross-linking
6)electron paramagnetic spectroscopy

Front 61

studying integral membrane proteins using freeze fracture electron microscopy

Back 61

Can resolve gross dimensions of membrane proteins, their density in the membrane and whether subunit (quaternary) structure exists. Cannot resolve details of tertiary structure.

Front 62

using nonionic detergents to study integral membrane proteins

Front 63

using limited enzyme digestion to determine the sidedness of the protein

Front 64

identifying transmembrane domains through hydropathicity plots

134

draw plot

Back 64

identifies runs of hydrophobic amino acid residues as potential transmembrane domains

Hydrophobicity is measured by the free energy required to transfer each segment of the poly peptide from a nonpolar solvent to an aqueous medium

peaks above the 0 are non-polar and have +delta G when placed in water.

Front 65

determining the spatial relationships between amino acid residues in the transmembrane domain using cross-linking

Front 66

using electron paramagnetic spectroscopy to monitor changes in conformation

Front 67

methods for studying peripheral membrane protein structure

method for studying anchored proteins

Front 68

what is Tc?

Back 68

transition temperature

membrane has a uniuqe Tc at which the membrane freezes...transfromrs from liquid to a gel

Front 69

draw gel vs liquid structure and plot

Back 69

..

Front 70

why does Tc vary membrane to membrane?

Back 70

environment and functional needs

Front 71

low Tc

Back 71

more fluid bilayer at room temperature...further from freezing

higher percent of unsaturated fats

short fatty acid chains

Front 72

what can cause low Tc in lipids?

Back 72

-unsaturated fatty acid chains...double bonds or short fatty acid chains

-

Front 73

what does high cholesterol do to Tc

Back 73

broadens temperature range over which gelling occurs....creates an intermediate fluidity in the temperature range

Front 74

how to maintain or change lipid fluidity

Back 74

Lipid fluidity can be controlled by synthesizing new phospholipids with different fatty acid properties

or

remodeling existing phospholipidfatty acid chains using enzymes that insert/remove double bonds in the chain

Fluidity can be maintained constant at different temperatures by this means

–important in cold-blooded animals, like pond dwelling fish which experience extremes of temperature.

Reduced temperatures in winter require a lower Tcto maintain membrane fluidity and so more unsaturated phospholipids are inserted into cell membranes

Hint 74

remember lower Tc means more liquid just like a frozen pond will have the water portion lower than the ice(gel)

Front 75

what about lipids with different headgroups or different lipids entirely

ex..

Back 75

asymmetry between being found in cytosolic membrane and exoplasmic membrane.

ex..
sphingomyelin-extracellular
phosphatidylcholine-extracell

phospatidylserine-intracellul

Front 76

why is asymmetry maintained in lipids?

Back 76

flip-flopping of lipids across the membrane is very energetically unfavourable...
very slow unless there is a flip-ase enzyme

Front 77

sumarize lipid mobility

Back 77

Lateral lipid diffusion – high – lipids can travel a micron in a 10^-6 seconds

Transverse diffusion – v. low

Front 78

what did fye and ediden discover?

Back 78

demonstrated diffuesion of proteins within the plane of the membrane in chimeric cells created by fusion

Hint 78

ed paid a fee to get a mouse and a human

Front 79

demonstrated diffuesion of proteins within the plane of the membrane in chimeric cells created by fusion

Back 79

fye ediden

Front 80

draw fye and ediden experiment

Back 80

deminstrates diffusion of proteins within the plane of the membrane

1)common integral membrane protein in mouse cells labled with primary antibody and secondary fluorescent secondary antibody that emmits green light
2)same is done for a protein in human cells, but uses red light
3)fuse cells
4)after 40 minutes..fully mixed

Front 81

FRAP

Back 81

fluorescence recovery after photobleaching

Front 82

draw Frap experiment

Back 82

aa

Hint 82

fluorescent recovery after photobleaching