Carbohydrates 3

Question 1

How many molecules of G-3-P enter the payoff phase?

Answer 1

2

Question 2

How many ATP are used in the prepatory phase?

Answer 2

2

Question 3

How many ATP are made during the payoff phase?

Answer 3

4

Question 4

What is the first reaction of glycolysis?

Answer 4

Phosphorylation of glucose

Question 5

How many ATP is used during the first stage of glycolysis? (phosphorylation of glucose) And what enzyme is used?

Answer 5

1 ATPHexokinase

Question 6

What is the second stage of glycolysis? And what is the enzyme?

Answer 6

Conversion of G - 6 - P to F-6-P Phosphohexose Isomerase

Question 7

Why does the second step of glycolysis proceed in both directions?

Answer 7

Reaction has a low free energy

Question 8

What is the stage of glycolysis apart from step 1 (phosphorylation of glucose) that requires ATP?

Answer 8

Phosphorylation of F-6-P to F-1,6 - bisP (stage 3)

Question 9

What is the catalyst for phosphorylation of F-6-P?

Answer 9

Phosphofructokinase -1

Question 10

What is the splitting part of Glycolysis?

Answer 10

Step 4 - which is the cleavage F-1, 6-bisP, forms two different triose sugars Catalyst is aldolase

Question 11

What is stage 5 of glycolysis?

Answer 11

Interconversion of triose sugarsEnzyme used it triose phosphate isomeraseDihydroxyacetone phosphate is converted to glyceraldehyde -3-phosphateForming 2 molecules of G-3-PG-3-P is the only molecule that can enter the payoff phase

Question 12

Which stage in glycolysis produces 2 molecules of NADH?

Answer 12

Stage 6, the oxidation of G-3-P to 1,3-bisPGThe catalyst is glyceraldehyde - 3 - phosphate dehydrogenaseThe first payoff reaction in glycolysis

Question 13

Reaction 6 (the oxidation of G-3-P to 1,3-bisPG) is coupled to which other reaction and why?

Answer 13

6 is coupled to 7 because 6 requires a lot of energy whilst 7 gives off a a lot of energy.

Question 14

Describe reaction 7 and what is the substrate?

Answer 14

P transfer from 1,3-bisPhosphoglycerate to ADP, 2 ATP produced, phosphoglycerate kinase enzyme usedSpontaneous since highly exergonic

Question 15

What is stage 8?

Answer 15

Conversion of 3, phosphoglycerate to 2, phosphoglycerateEnzyme is phosphoglycerate mutase

Question 16

What step of glycolysis is enolase used in?

Answer 16

Dehydration 2-PG to PEP (phosphoenolpyruvate)

Question 17

Where does the ADP in the last stage of glycolysis get the phosphate?

Answer 17

PEP

Question 18

Describe the last stage of glycolysis

Answer 18

Transfer of P from PEP to ADP2 ATP produced, highly exergonic,Pyruvate producedEnzyme is pyruvate kinase

Question 19

Where does NAD+ come from in the cell?

Answer 19

Niacin an essential vitamin

Question 20

What is the difference between substrate level phosphorylation and respiration linked phosphorylation ?

Answer 20

Substrate level - requires soluble enzymes and chemical intermediatesRespiration linked means membrane bound enzymes and gradients of protons

Question 21

What compound is used to replenish NAD+?

Answer 21

The different fates of pyruvate

Question 22

What is NAD+ used for?

Answer 22

The reduction of various intermediate metabolites

Question 23

What are the three fates of pyruvate?

Answer 23

Citric acid cycle, producing water and carbon dioxideFermentation to lactateFermentation to CO2 and Ethanol

Question 24

How is pyruvate converted into ethanol?

Answer 24

Pyruvate + pyruvate carboxylase = AcetaldehydeAcetaldehyde + Alcohol dehydrogenase + NADH = Ethanol + NAD+

Question 25

Why can’t we make ATP via oxidative phosphorylation during intense exercise?

Answer 25

Not enough oxygen

Question 26

How is ATP made instead during intense exercise?

Answer 26

Substrate level phosphorylation producing lactate

Question 27

Where is the lactate converted into glucose, and what is this process called?

Answer 27

Liver, gluconeogenesis

Question 28

What is the interaction between the muscle and the liver called?

Answer 28

The cori cycle

Question 29

What is pyruvate converted into in aerobic conditions?

Answer 29

Acetyl Co-A, in mitochindria, NADH is formed