glycolysis

Question 1

What is glycolysis

Answer 1

occurs in the cytosol, occurs under anaerobic conditions, yields 2 pyruvate, 2 net ATP and 2 NADH. Consumes glucose, 2ADP, 2NAD+

Question 2

Preparatory Phase

Answer 2

steps 1-5, prepares glucose for cleavage, consumes

2 atp

Question 3

Step 1

Answer 3

phosphorylation of glucose is catalysed by hexokinase, glucose 6-phosphate formed from glucose, irreversible due to large negative delta G

Helps keep glucose in the cell

Consumes 1 ATP

Question 4

Step 2

Answer 4

Glucose rearranged to fructose 6-phosphate, catalyzed by phosphohexose isomerase,

reversible

Question 5

Step 3

Answer 5

First reaction where sugar is committed to glycolysis, can’t go to a different metabolic pathway.

Phosphofructokinase catalyzes addition of phosphate to fructose 6-phosphate resulting in fructose 1,6 biphosphate.

Ensures that both molecules are contained in the cell after cleavage of glucose.

Irreversible

Consumes 1 ATP

Question 6

Step 4

Answer 6

Aldolase breaks down fructose 1,6 biphosphate into dihydroxyacetone phosphate and glyceraldehyde 3 phosphate.

Reversible.

Question 7

Step 5

Answer 7

Dihydroxyacetone phosphate converted to glyceraldehyde 3-phosphate by triose phosphate isomerase,

reversible.

Question 8

Payoff Phase

Answer 8

Produces 4 ATP and 2 NADH

Steps 6-10

Question 9

Step 6

Answer 9

glyceraldehyde 3 phosphate dehydrogenase catalyzes oxidation reduction reaction.

Glyceraldehyde 3 phosphate and inorganic phosphate turn into 1,3 biphosphoglycerate and generate 2 NADH.

Reversible

Forms high energy bond in product.

Question 10

Step 7

Answer 10

phosphoglycerate kinase catalyzes the conversion of 1 3-bisphosphoglycerate to 3-phosphoglycerate.

ATP is formed due to energy from bond in 1,3 biphosphoglycerate breaking.

Reversible.

Question 11

Step 8

Answer 11

Phosphoglycerate mutase catalyzes formation of 2 phosphoglycerate from 3 phosphoglycerate

reversible.

Question 12

Step 9

Answer 12

enolase catalyzes the conversion of 2-phosphoglycerate to phosphoenolpyruvate, removal of water causes high energy enol-phosphate linkage.

Reversible.

Question 13

Step 10

Answer 13

pyruvate kinase catalyzes the conversion of phosphoenolpyruvate to 2 pyruvate and 2 ATP

irreversible.

Question 14

What happens during fermentation?

Answer 14

Pyruvate is consumed in anaerobic conditions, occurs in cytosol.

Helps keep glycolysis happening by regenerating NAD+ from NADH through production of lactate

Alcohol produced by yeast under anaerobic conditions.