Glycolysis

Question 1

the net products are

Answer 1

2 ATP
2 NADH
2 pyruvate

Question 2

the two phases are

Answer 2

investment phase (input of 2 ATP)
payoff phase (net products are produced)

Question 3

oxidoreductases

Answer 3

catalyze oxidation-reduction (redox) reactions

Question 4

transferases

Answer 4

catalyze transfer of functional groups from one molecule to another

Question 5

hydrolases

Answer 5

catalyze hydrolytic cleavage

Question 6

lyases

Answer 6

catalyze removal/addition of a group from/to a double bond or other cleavages involving electron arrangements

Question 7

isomerases

Answer 7

catalyze intramolecular rearrangement

Question 8

mutases

Answer 8

shifting of functional groups from one position to another in the same molecule

Question 9

ligase

Answer 9

catalyze reaction in which two molecules are joined

Question 10

kinases

Answer 10

catalyze reaction involving transfer of phosphoryl group

Question 11

overview of glycolysis is to reduce/oxidize what to what?

Answer 11

glucose is oxidized to pyruvate and NAD+ is reduced to NADH

Question 12

reaction 1: hexokinase

Answer 12

it is the conversion of D-glucose to glucose-6-phosphate
hexokinase enzyme assists in phosphorylaion by transfering the phosphorous group from Mg2+ATP to the D-glucose to product G6P
ADP is also a product

Question 13

reaction 2: glucose-6-phosphate isomerase

Answer 13

it is the conversion of G6P to fructose-6-phosphate (F6P) by catalyzing the intramolecular arrangement
G6 isomerase enzyme assists in isomerization by converting the six-membered ring into a five-membered ring (so that carbon 1 is now on the outside of the ring)

Question 14

reaction 3: phosphofructokinase

Answer 14

it is the conversion of F6P to fructose-1,6-biphosphate (FBP) by a transfer of a phosphote group
phosphofructokinase enzyme assists in the phosphorylation by transfering another phosphorous group from Mg2+ATP to the product FBP
ADP is also a product

Question 15

reaction 4: aldolase

Answer 15

it is the split of FBP into two sugars that are isomers of one another - dihydroxyacetone phosphate (DHAP) and glyceraldehyde-3-phosphate (GAP)
aldolase enzyme assists by catalyzing the cleavage of FBP to yield the two molecules

Question 16

reaction 5: triose phosphate isomerase (TPI)

Answer 16

it is the rearrangement of dihydroxyacetone phosphate (DHAP) to GAP so it can be used in the rest of glycolysis (GAP from reaction 4 continues to reaction 6)
TPI assists by rapidly catalyzing the intramolecular bonds for rearrangement

Question 17

reaction 6: glyceraldehyde-3-phosphate dehydrogenase (GAPDH)

Answer 17

it is the conversion of GAP to 1,3-biphosphoglycerate (BPG)
the first step is that GAP is oxidized by NAD+ thus the second step is phosphorylated by the addition of a free phosphate group to make BPG, the reaction catalyzed by GAPDH enzyme
NADH is also a product

Question 18

reaction 7: phosphoglycerate kinase (PGK)

Answer 18

it is the conversion of BPG to 3-phosphoglyercate (3PG) by PGK enzyme
BPG losses a phosphate group to begin and it is transfered to an ADP molecule to become ATP thus 3PG is formed
*this is the first production site of ATP (two molecules are being synthesizes throughout thus the net production of ATP is at 0 now)

Question 19

reaction 8: phosphoglycerate mutase

Answer 19

it is the rearrangement of

3-phosphoglycerate (3PG) to 2-phosphoglycerate (2PG) using the phosphoglycerate mutase enzyme

Question 20

reaction 9: enolase

Answer 20

the enolase enzyme removes a molecule of water from 2-phosphoglycerate to form phosphoenolpyruvate (PEP) and water

Question 21

reaction 10: pyruvate kinase

Answer 21

it is the transfer of the phosphate group of PEP to ADP to form pyruvate and ATP (2 molecules) using the pyruvate kinase enzyme

Question 22

what happens afterwards?

Answer 22

under aerobic conditions (presence of oxygen) the pyruvate produced enters the pyruvate dehydrogenase complex to be converted to acetyl-CoA then to the Krebs cycle
under anaerobic conditions (absence of oxygen) the pyruvate produced enters fermentation to be used for the regeneration of NAD+

Question 23

takes place in what part of the cell?

Answer 23

cytoplasm

Question 24

do this process require oxygen?

Answer 24

no