Glycolysis

Question 1

powerhouse of cell?

Answer 1

mitochondrial matrix –> where aerobic metabolism occurs

Question 2

if you havent had breakfast, what do you use as energy source?

Answer 2

fatty acids (fat)

Question 3

two dehydrogenating reagents

Answer 3

NAD/FAD

Question 4

fatty acids undergo

Answer 4

beta oxidation (consisting of dehydrogenation rxns)

Question 5

long fatty acid chain in oxidation..

Answer 5

go through cycle over and overuntil used up –> creates a pool of acetyl coa for tca cycle

Question 6

c from acetyl coa in tca become….and c from oxaloacetate in tca become….

Answer 6

acetyl coa –> new oxaloacetate

oxaloacetate –> co2

Question 7

oxygen comes from

Answer 7

water

Question 8

in etc oxygen becomes

Answer 8

water

Question 9

why cant nadh and oxygen react directly in etc ?

Answer 9

because of the activation energy barrier….there is no enzyme to allow direct e transfer

Question 10

how do protons in etc get across lipid bilayer?

Answer 10

ATP synthase allows protons to move down their gradient –> as they travel down, conformational changes of the synthase resynthesizes ATP (this is ox. phosphorylation)

Question 11

overall glycolytic path

Answer 11

d-glucose –> 10 steps catalyzed by 10 enzymes –> 2 pyruvate

Question 12

anaerobic fate of pyruvate?

Answer 12

lactic acid

Question 13

glycolysis is a net ____ rxn that takes place through ____ rxns

Answer 13

oxidation; dehydrogenation

Question 14

rbc atp production?

Answer 14

rbc dont have mitochondria so glucose is converted to lactate –> atp from glycolysis is the only source of atp for those cells

Question 15

glucose storage polymer

Answer 15

glycogen

fastest source of G6P when you need energy quick

Question 16

atp yield from complete combustion of one glucose

Answer 16

30-32 atp

Question 17

steady state ATP/ADP+AMP ratio

Answer 17

maintained far from equilibrium –> very exergonic!
ATP is way higher
equilibrium = death

Question 18

what happens when ATP/Adp ratio hits equilibrium?

Answer 18

common cause of cell death is oxygen deprivation –>atp system goes to equilibrium –> cell cant maintain itself -> death cascade due to drop in atp

Question 19

aerobic vs anaerobic glycolysis

Answer 19

a= glucose +2NAD,2ADP,2Pi–> 2 pyruvate + 2nadh,2atp

an=glucose+2adp,2pi –> 2 lactate +2atp

Question 20

lactic acidosis

Answer 20

too much acid

blood pH goes down - disrupts homeostasis

Question 21

acidosis in bad circulation vs anemia

Answer 21

bad cir =atp drops, cells use both a and an respiration to restore atp levels –> lactate
anemia= not enough rbc, tissues arent getting enough oxygen to run oxidative phosphorylation so lots of lactate

Question 22

glucose vs fructose vs pyruvate structure

Answer 22

glucose is an aldose - carbonyl on C1
fructose is a ketose - carbonyl on C2
pyruvate is an alpha keto acid (carbonyl on alpha c)

Question 23

kinase

Answer 23

adds a phosphate, favorable reaction, uses atp and makes adp

Question 24

mutase

Answer 24

moves phosphate to another hydroxyl group

Question 25

how many isomerase reactions in glycolysis?

Answer 25

2

Question 26

hydratase/dehydratase

Answer 26

add/remove water

Question 27

aldolase

Answer 27

c-c bond breaks between alpha and beta c; beta becomes carbonyl

Question 28

aldol condensation

Answer 28

form a c-c bond

Question 29

dehydrogenase

Answer 29

oxidation

Question 30

where does glycolysis take place?

Answer 30

cytosol

Question 31

intermediates and enzymes of glycolysis

Answer 31

1. glucose-(hexokinase) - glusoce 6 phosphate 2. G6P -(phosphoglucoisomeras) - fructose 6 phosphate 3. fructose 6 phosphate -(phosphofructokinase 1) - fructose 1,6,bisphosphate 4. fructose 1 6 bisphosphate -(fructo-bisphosphate aldolase) - glyceraldahye3phosphate 5. dihydroxyacetone phosphate - (TPI) -glyceraldehyde 3 phosphate 6.glyceraldehyde 3 phosphate (glyceraldehyde phosphate dehydrogenase) - 1,3 bisphosphoglycerate 7. 1,3 bpg -(phosphoglycerate kinase pgk) - 3 phosphoglycerate 8. 3pg - (phosphoglycerate mutase) - 2 phosphoglycerate 9. 2 pg - (enolase) - phosphoenolpyruvate (pep) 10. pep - (pyruvate kinase) - pyruvate

Question 32

which steps use ATP in glycolysis?

Answer 32

1 (hexokinase) 3 (phosphofructokinase) both irreversible

Question 33

which steps in glycolysis make atp?

Answer 33

7 (phosphoglyccerate kinase) | 10 (pyruvate kinase)

Question 34

after step 1 of glycolysis, can g6p do anything else?

Answer 34

yes, it can go through glycolysis, or glycogen synthesis, or pentose phosphate pathway after step 1 is where glycogen can feed into glycolysis

Question 35

which gly step is the aldose-ketose isomerization?

Answer 35

step 2 g6p -->fructose 6 phosphate uses phosphoglucoisomerase

Question 36

which step is the highly regulated commitment step? irreversible

Answer 36

fructose 6 phosphate --> fructose ,6bisphosphate | uses (pfk)phosphofructokinase and atp to adp

Question 37

g3p dehydrogenase

Answer 37

uses S as a good leaving group nad --> nadh aldehyde -->mixed acid anhydride g3p -->glycerate bisphosphate

Question 38

which reaction in gly uses an irreversible tautomerization using atp?

Answer 38

10, pyruvate kinase forms pyruvate (keto)

Question 39

3 irreversible steps of glycolysis

Answer 39

1 (hexokinase), 3(pfk), 10(pyruvate kinase) | **must be bypassed in gluconeogenesis in liver

Question 40

NAD supply for glycolysis is replenished by...

Answer 40

glyceol 3P and malate/asparate shuttles

Question 41

nad supply for anaerobic glycolysis is replenished by...

Answer 41

lactate dehydrogenase

Question 42

3 cytosol-mito transporters that dont exist

Answer 42

oxaloacetate nad(H) acetyl coa

Question 43

2 shuttles for nad/nadh

Answer 43

``` glycerol phosphate (most tissues) malate aspartate (liver, kidney, heart) ```

Question 44

enzyme for g3p shuttle?

Answer 44

glycerol phosphate dehydrogenase

Question 45

net reaction for glycerol phosphate shuttle

Answer 45

nadh (cyt) + flavoprotein(ox) --> nad+ (cyt) + flavoprotein (red) flavoprotein accept e irrevesible

Question 46

which shuttle requires a transaminase rxn?

Answer 46

malate aspartate shuttle

Question 47

net reaction for malate aspartate shuttle

Answer 47

nadh (cyt) + nad+(mito) --> nad+ (cyt) + nadh (mito)

Question 48

how malate aspartate shuttle works?

Answer 48

nadh reduces oxaloacetate into malate and nad+ is regenerated malate passes through imm via malate shuttle malate reacts with nad inside to make nadh and oxaloacetate via malate dehydrogenase e on nadh feed into etc, producing nad+ transaminase rxn takes oxaloacetate and glutamate to make alpaketoglutarate and aspartate aspartate diffuses across imm into cytosol and a transaminase rxn happens in reverse to make oxaloacetate net movement of e (reversible)

Question 49

anaerobic glycolysis

Answer 49

pyruvate + nadh --> lactate + NAD+ uses lactate dehydrogenase reversible (direction depends on nadh/nad ratio)

Question 50

cells that produce lactate and cells that use lactate

Answer 50

rbc and working muscles produce it | liver uses it for gluconeogenesis and resting muscle and heart use it as fuel

Question 51

efficiency vs power

Answer 51

e=atp produced/amount of fuel consumed p=atp produced/sec

Question 52

aerobic is more ____ but anaerobic is more____

Answer 52

efficient (15x more atp) | less efficient but potentially 30x faster

Question 53

if anaerobic is 30x faster, what is the drawback?

Answer 53

more atp/sec uusing glycogen BUT lactic acidosis creates acidic blood and muscles slow down

Question 54

physiological anaerobic threshold

Answer 54

lactate production by working muscle exceeds rate of utilization by other tissues

Question 55

aerobic pathway for lactate utilization

Answer 55

lactate --> pyruvate -->acetyl coa --> co2

Question 56

gluconeogenesis | where? how?

Answer 56

2 lactate enter liver | liver uses 6 atp in gluconeogenesis to produce 1 glucose

Question 57

cori cycle

Answer 57

glucose -->2 lactate and 2 atp (RBC) 2 lactate +6 atp--> glucose (liver) quickly more atp is being used than produced

Question 58

alanine can be made from

Answer 58

pyruvate

Question 59

serine can be made from

Answer 59

3phosphoglycerate

Question 60

acetyl coa can make...

Answer 60

fatty acids --> triglycerides