Carbs 3 Flashcards
What is an Exergonic reaction ?
A reaction where energy is released. This kind of reaction occurs spontaneously (Delta G must be negative)
What is an Endergonic reaction ?
A reaction that requires energy to be driven. These kinds of reactions are NOT spontaneous
What is an Exothermic reaction ?
A reaction that releases energy as heat or light
What s an Endothermic reaction ?
A reaction where the system absorbs energy from its surroundings
How many ATP are used/gained in the preparatory phase of Glycolysis ?
2 ATP Used
What is the next step after Glucose-6-Phosphate in Glycolysis & what enzyme catalyses this reaction ?
Fructose-6-Phosphate
Catalyst: Phosphohexose Isomerase
What is the name of the enzyme which catalyses the transition of Glucose to G-6-P ?
Hexokinase
Where is the first ATP gained/used in the preparatory phase ?
When Glucose turns into G-6-P ATP is used
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
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
How many ATP are used/gained during the pay-off phase of Glycolysis ?
4 ATP are gained
What is the net gain/loss of ATP during Glycolysis ?
2 ATP Gained
Is Glycolysis an Anaerobic reaction or an Aerobic reaction ?
Anaerobic, occurs when no oxygen present.
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
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
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
What does 2-Phosphoglycerate turn into in the pay-off phase of Glycolysis ? What enzyme catalyses this reaction ?
Phosphenopyruvate
Enzyme: Enolase
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.
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.
Name the steps plants take to form Ethanol with Pyruvate.
Pyruvate -> Acetaldahyde -> Ethanol
Enzyme 1: Pyruvate Decarboxylase
Enzyme 2: Alcohol Dehydrogenase
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
Does the pyruvate to lactate reaction occur in the mitochondria ?
No. It is between liver & muscle
When oxygen is present what is the fate of Pyruvate ?
Acetyl-CoA
What is the name of the enzyme that changes Pyruvate to Lactate ?
Lactate Dehydrogenase
What is the name of the enzyme that changes Pyruvate to Acetyl-CoA ?
Pyruvate Dehydrogenase
Where does the reaction of Pyruvate to Acetyl-CoA occur ?
In the mitochondria
