Glycolysis

Question 1

what kind of cell is glycolysis found in?

Answer 1

nearly all prokaryotic and eukaryotic cells

Question 2

where does glycolysis occur in eukaryotic cells?

Answer 2

in the cytosol

Question 3

what does glycolysis convert?

Answer 3

1 glucose molecule into 2 molecules of pyruvate

Question 4

what are the 2 major functions of glycolysis

Answer 4

genearte ATP
intermediates serve as building blocks for the biosynthesis of other biomolecules such as amino acids and fats

Question 5

what key molecules of metabolism are small molecules usually processed into

Answer 5

acetyl Coa

Question 6

describe stage 1 of glycolysis

Answer 6

net input of energy stage
trapping glucose
modified so that it can be cleaved into a pair of phosphorylated 3- carbon compounds

Question 7

describe stage 2 of glycolysis

Answer 7

net output of energy stage
oxidizing the 3-carbon compounds to pyruvate while generating two molecules of ATP

Question 8

what’s the first step of glycolysis. irreversible or reversible?

Answer 8

phosphorylation of glucose by hexokinase (irreversible)

Question 9

what do kinases do

Answer 9

transfer a phosphate to their substrate from ATP or another high energy molecule

Question 10

what does phosphorylation of glucose mean in the first step

Answer 10

allows glucose to not get out of the cell

Question 11

what is an isomerization reaction?

Answer 11

no atoms lost, just a rearrangement of them

Question 12

which steps of glycolysis consume ATP

Answer 12

1 and 3

Question 13

which steps of glycolysis produce ATP

Answer 13

7-10

Question 14

what are the regulatory steps of glycolysis

Answer 14

1, 3 and 10

Question 15

what are dehydrogenase enzymes

Answer 15

enzymes that catalyze redox reactions

Question 16

what’s the first energy producing step in glycolysis

Answer 16

step 7 - catalyzed by phosphoglycerate kinase

Question 17

what kind of reaction is glycolysis regarding oxygen

Answer 17

anaerobic glycolysis - does not need oxygen

Question 18

how can pyruvate regenerate NAD+?

Answer 18

it can be converted to ethanol by alcohol dehydrogenase (second step of the two step reaction)
it can be converted directly to lactate by lactate dehydrogenase

Question 19

how do the regulatory enzymes in glycolysis decrease or increase their catalytic activity

Answer 19

the binding of allosteric effectors or covalent modification

Question 20

what tissues do glycolysis occur in?

Answer 20

muscle and liver, but the reason why is very different

Question 21

what is glycolysis for in muscle

Answer 21

providing ATP for muscle contraction

Question 22

what’s the most important enzyme in mammalian glycolysis

Answer 22

phosphfructosekinase

Question 23

what does a drop in PH in muscle do

Answer 23

inhibits phosphofructosekinase (PFK) by enhancing the effect of ATP

Question 24

why is the phosphorylation of glucose to glucose 6 phosphate not the first committed step in glycolysis?

Answer 24

because glucose 6 phosphate can enter many other pathways

Question 25

what is pyruvate kinase inhibited by? what about activated? (in muscle)

Answer 25

it is inhibited by ATP (duh) and activated by fructose 1,6 bisphosphate ( it basically warns it that there’s stuff coming its way)

Question 26

what is one of the major functions of the liver for glucose

Answer 26

to maintain glucose levels in the blood

Question 27

what are the forms of glucose in the liver?

Answer 27

it is either stored as glycogen or converted via glycolysis to molecules that serve as building blocks for the synthesis of other molecules

Question 28

what are the major regulators of PFK in muscle

Answer 28

ATP and PH

Question 29

what’s the major inhibitor of PFK in the liver

Answer 29

citrate

Question 30

whats an allosteric activator of PFK in the liver

Answer 30

fructose 2,6 bisphosphate - it basically blunts the inhabitation of ATP

Question 31

what is the hexokinase of the liver

Answer 31

glucokinase