Overview of Glycolysis

Question 1

What is another name for glycolysis?

Answer 1

Embden-Meyerhof pathway

Question 2

What are the final products of glycolysis?

Answer 2

2 pyruvate + 2ATP + 2NADH + 2 H20 + 4 H+

Question 3

How many enzymatic reactions are involved in glycolysis?

Answer 3

10

Question 4

Where does glycolysis take place?

Answer 4

In the cytosol of the cell

Question 5

What is the net reaction of glycolysis?

Answer 5

glucose + 2 NAD+ + 2ADP + 2 Pi&raquo_space;» 2 pyruvate + 2 NADH + 2 ATP + 2 H20 + 4 H+

Question 6

How many pyruvate molecules are generated from 1 molecule of glucose in glycolysis?

Answer 6

2

Question 7

How many ATP molecules are generated in glycolysis?

Answer 7

2

Question 8

What is the first step of glycolysis catalyzed by?

Answer 8

Hexokinase

Question 9

What is the product of the first step of glycolysis?

Answer 9

Glucose-6-phosphate (G6P)

Question 10

What does hexokinase do in the first step of glycolysis?

Answer 10

Transfers a high energy phosphoryl group from ATP to glucose

Question 11

What is the energy cost of the first step of glycolysis?

Answer 11

1 ATP

Question 12

How selective of an enzyme is hexokinase?

Answer 12

Relatively non-specific; will bind mannos, fructose, and galactose

Question 13

What is the cofactor of hexokinase?

Answer 13

Mg2+

Question 14

What inhibits hexokinase? What kind of inhibitor is it?

Answer 14

ATP; competitive inhibitor

Question 15

What are the two major functions of glycolysis?

Answer 15

1) Generate ATP

2) Form molecules that are the precursors for amino acids and fatty acids.

Question 16

What is the only fuel used by the brain under starvation conditions and the only fuel used by red blood cells at all?

Answer 16

Glucose

Question 17

Into what two stages can glycolysis be broken into?

Answer 17

1) Three-step conversion of glucose into fructose 1, 6-bisphosphate (a compound that can readily be cleaved into phosphorylated 3-carbon units).
2) Generation of ATP through the oxidation of the 3-carbon units to pyruvate.

Question 18

In which steps of glycolysis is ATP consumed (used)?

Answer 18

1) Conversion of glucose to glucose-6-phosphate (-1 ATP)

2) Conversion of fructose-6-phosphate to fructose 1,6 bisphosphate (-1 ATP)

Question 19

In which steps of glycolysis is ATP produced (made)?

Answer 19

1) Conversion of 1,3-bisphosphoglycerate to 3-Phosphoglycerate (catalyzed by Phosphoglycerate kinase) (+2 ATP)
2) Conversion of phosphoenolpyruvate to pyruvate (+2 ATP)

Question 20

What happens to the 2 NADH produced in glycolysis?

Answer 20

Shunted into the electron transport for ATP formation and regeneration of NAD+.

Question 21

What happens to the pyruvate produced in glycolysis under aerobic conditions?

Answer 21

Is enters the TCA cycle for complete oxidation to CO2 and H20 and synthesis of more ATP

Question 22

What happens to pyruvate under anaerobic conditions?

Answer 22

1) In muscle, pyruvate is converted to lactate to regenerate NAD+ through homolactic fermentation.
2) In yeast, pyruvate is converted to NAD+ and ethanol through alcoholic fermentation