Glycolysis

Question 1

Why is the the 2834 kJ/mol of free energy not released as heat?

Answer 1

1. Biological systems cannot utilise heat as a source of energy;
2. No single reaction of metabolism requires this amount of energy to be released in one step;
3. Always need to overcome the activation energy. Enzymes are capable of effecting only small changes when they catalyse biological reactions, releasing the energy in steps.

Question 2

What are the products of glycolysis?

Answer 2

2 Pyruvate
2ATP
2 NADH + 2H+

Question 3

Where does glycolysis occur?

Answer 3

In the cytosol

Question 4

How is energy release in glycolysis and in what form?

Answer 4

energy is released in usable amounts (~ -30 kJ/mol) in the form of chemical energy, with ATP being the energy carrier.

Question 5

Which coenzyme is used with phosphate?

Answer 5

ATP/ADP

Question 6

Which co enzyme is used in oxidation/reductions?

Answer 6

NADH/NAD+

Question 7

How many ATPs

Prime glycolysis
Produced from the pathway
Net gained

Answer 7

Prime glycolysis- 2ATP
8 ATP produced from the pathway

8 ATP net gained

Question 8

How many NADH generated from glycolysis?

Answer 8

2 NADH

Question 9

Glycerol.

Describe its structure and its role in glycolysis

Answer 9

CH2OH-CHOH-CH2OH

Metabolised to intermediate in glycolysis- dihydroxyacetone phosphate

Question 10

What can happen to dihydroxyacetone ?

Answer 10

converted to pyruvic acid

or used in gluconeogenesis to make glucose-6-phosphate

Question 11

What is the role of kinases?

Answer 11

Phosphorylates

Question 12

What is the role of phosphatases?

Answer 12

dephosphorylates

Question 13

What is the structure of acetone?

Answer 13

Ketone w/ two methyl groups

CH3-C=O-CH3

Question 14

Describe the first step in glycolysis

Answer 14

Glucose converted to glucose-6-phosphate by HexoKinase with Mg2+ as a cofactor

ATP is converted to ADP in this reaction to power the transport proteins to transport glucose

Question 15

Describe the second step in glycolysis

Answer 15

Glucose-6-phosphate converted to fructose-6-phosphate via Phosphoglucose isomerase

Question 16

Describe the third step in glycolysis

Answer 16

fructose-6-phosphate converted to Fructose-1,6-Bisphosphate via phosphofructokinase

ATP is converted to ADP

Question 17

Describe the fourth step in glycolysis

Answer 17

Fructose-1,6-Bisphosphate converted to either Dihydroxyacetone phosphate OR Glyceraldehyde-3-phosphate via Aldolase

THIS IS REVERSIBLE

Question 18

Describe the 5th step in glycolysis

Answer 18

Dihydroxyacetone phosphate to Glyceraldehyde-3-phosphate via Triosephosphate isomerase

REVERSIBLE

Question 19

Describe the 6th step in glycolysis

Answer 19

Glyceraldehyde-3-phosphate to 1,3-bisphosphoglycerate via GAP hydrogenase

NAD+ goes to NADH + H+
Reversible

Question 20

Describe the 7th step of glycolysis

Answer 20

1,3-bisphosphate to 3-phosphoglycerate via phosphoglycerate kinase

ADP going to ATP

Question 21

Describe the 8th Step in glycolysis

Answer 21

3-phosphoglycerate to 2-phosphate via phosphoglycerate mutase

Question 22

Describe the 9th step in glycolysis

Answer 22

2-phosphoglycerate to phosphoenolpyruvate via enolase

H2O is produced

Question 23

Describe the 10th step in glycolysis

Answer 23

phosphoenolpyruvate to pyruvate via pyruvate kinase

With ADP to ATP