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Flashcards in Carbs 3 Deck (26):
1

What is an Exergonic reaction ?

A reaction where energy is released. This kind of reaction occurs spontaneously (Delta G must be negative)

2

What is an Endergonic reaction ?

A reaction that requires energy to be driven. These kinds of reactions are NOT spontaneous

3

What is an Exothermic reaction ?

A reaction that releases energy as heat or light

4

What s an Endothermic reaction ?

A reaction where the system absorbs energy from its surroundings

5

How many ATP are used/gained in the preparatory phase of Glycolysis ?

2 ATP Used

6

What is the next step after Glucose-6-Phosphate in Glycolysis & what enzyme catalyses this reaction ?

Fructose-6-Phosphate
Catalyst: Phosphohexose Isomerase

7

What is the name of the enzyme which catalyses the transition of Glucose to G-6-P ?

Hexokinase

8

Where is the first ATP gained/used in the preparatory phase ?

When Glucose turns into G-6-P ATP is used

9

What is the next stage after the production of F-6-P & what is the name of the enzyme which catalyses this reaction ?

Fructose-1-6-Bis-phosphate & Phosphofructokinase-1

10

What is the final step of the preparatory phase of Glycolysis & what enzyme catalyses this reaction ?

Fructose-1-6-Bis-Phosphate to G-3-P & Adolase

11

How many ATP are used/gained during the pay-off phase of Glycolysis ?

4 ATP are gained

12

What is the net gain/loss of ATP during Glycolysis ?

2 ATP Gained

13

Is Glycolysis an Anaerobic reaction or an Aerobic reaction ?

Anaerobic, occurs when no oxygen present.

14

Whats happens to G-3-P in the first stage of the pay-off phase of Glycolysis ? What enzyme catalyses this reaction ?

G-3-P turns into 1-3-Bis-Phosphoglycerate
Enzyme: G-3-P Hydrogenase

15

What is the 2nd stage of the pay-off phase of Glycolysis ? and what enzyme catalyses this reaction ?

1-3-Bis-Phosphoglycerate turns into 3-Phosphoglycerate
Enzyme: Phosphoglycerate Kinase

16

What is the 3rd stage of the pay-off phase of Glycolysis ? What enzyme catalyses this reaction ?

3-Phosphoglycerate turns into 2-Phosphoglycerate
Enzyme: Phosphoglycerate Mutase

17

What does 2-Phosphoglycerate turn into in the pay-off phase of Glycolysis ? What enzyme catalyses this reaction ?

Phosphenopyruvate
Enzyme: Enolase

18

How is Phosphenopyruvate turned into Pyruvate ? What enzymes catalyses this reaction ?

Phosphenopyruvate turns into PEP then into Pyruvate .
PEP to Pyruvate catalyzed by Pyruvate Kinase.

19

Name 3 fates of Pyruvate after Glycolysis ?

Plants: Ethanol production
Humans: Lactate & Acetyl-CoA
It is dependent on what the body needs at a certain time.

20

Name the steps plants take to form Ethanol with Pyruvate.

Pyruvate -> Acetaldahyde -> Ethanol
Enzyme 1: Pyruvate Decarboxylase
Enzyme 2: Alcohol Dehydrogenase

21

What happens to Pyruvate in cells lacking oxygen (exercising muscle) ?

Lactic acid (lactate) is generated.
In exercising muscle, body does not have time to generate ATP from Oxidative phosphorylation therefore substrate level phosphorylation occurs.
Lactate -> Glucose (In liver) & liver pays oxygen debt to muscles.
This is called Gluconeogenesis

22

Does the pyruvate to lactate reaction occur in the mitochondria ?

No. It is between liver & muscle

23

When oxygen is present what is the fate of Pyruvate ?

Acetyl-CoA

24

What is the name of the enzyme that changes Pyruvate to Lactate ?

Lactate Dehydrogenase

25

What is the name of the enzyme that changes Pyruvate to Acetyl-CoA ?

Pyruvate Dehydrogenase

26

Where does the reaction of Pyruvate to Acetyl-CoA occur ?

In the mitochondria