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Flashcards in Glycolysis Deck (27):
1

Carbohydrates are broken down into ____ (glucose, galactose), which are then absorbed by intestinal lining by ___ ____

monosaccharides; facilitated diffusion

2

When your body intakes carbs and fats and breaks them down to form ATP, what are the chemical waste products?

CO2, H2O

3

Where does glycolysis occur in the cell?

cytosol

4

Name the requirements of glycolysis and also the products

requirements: Glucose, 2 Pi, 2 ADP, 2 NAD+
products: 2 pyruvate, 2 ATP, 2 NADH, 2H, 2H2O

5

In glycolysis, one glucose molecule is covered to ___ pyruvate molecules

2

6

Glycolysis is the only pathway to produce ATP without ____

oxygen

7

Availability of glucose for glycolysis is controlled by transport into the cell, which is regulated by _____

insulin

8

Glucokinase and Hexokinase can both catalyze the first step of glycolysis. Name the differences between them in regards to location, affinity, and inhibition by G-6-P

Glucokinase: liver and kidney; low affinity; not inhibited

Hexokinase: all tissues; high affinity; inhibited

9

True or false? The function of glucokinase is to remove glucose from the blood following a meal, while hexokinase acts at a constant rate

true

10

What is the key regulatory step of glycolysis and also the committed step?

F-6-P to F-1,6-BP

enzyme is phosphofructokinase

11

In the 6th step of glycolysis, G-3-P to 1,3-BPG, NAD+ must be regenerated for glycolysis to continue. True or false?

True

12

1,3-BPG is the source of 2,3-BPG in ____

erythrocyte

13

Enolase is inhibited by ____

fluoride

note: for estimation, blood sample is collected in tubes containing fluoride to inhibit glycolysis

14

After glycolysis has finished, what determines which of the two pathways is followed (aerobic or anaerobic)?

redox state of tissue

15

In aerobic glycolysis, pyruvate is converted to acetyl-CoA in the ___ for the TCA cycle

mitochondria

16

The oxidation of acetyl-CoA by the TCA will account for additional ___ molecules of ATP per glucose molecule

36

17

Under aerobic conditions, NADH produced may be effectively reoxidized by the mitochondria through the "____ ____"

shuttle system

18

In regards to anaerobic glycolysis, what enzyme is used to regret NAD+?

lactate dehydrogenase

19

The NAD+ must be regenerated for glycolysis to continue. Since NADH cannot cross mitochondrial membrane, the reducing equivalents from the NADH formed in glycolysis are taken up into mitochondria for oxidation by ____ mechanism

shuttle

20

List the steps of glycolysis that use ATP and produce ATP

Use ATP:
glucose to G-6-P = -1 ATP
F-6-P to F-1,6,-BP = -1 ATP
------------
-2 ATP

Produce ATP:
Glycerate-1,3-BP to 3-P-glycerate = + 2 ATP
PEP to pyruvate = +2ATP
------------
+4 ATP

net gain: 2 ATP

21

Regulation of glycolysis is controlled primarily by three enzymes: hexokinase, PFK-1, and pyruvate kinase. Give the activator and inhibitor of hexokinase

Activator: none

inhibitor: G-6-P, ATP

22

Regulation of glycolysis is controlled primarily by three enzymes: hexokinase, PFK-1, and pyruvate kinase. Give the activator and inhibitor of PFK-1

activator: F-2,6-bP, AMP

inhibitor: Citrate, ATP

23

Regulation of glycolysis is controlled primarily by three enzymes: hexokinase, PFK-1, and pyruvate kinase. Give the activator and inhibitor of Pyruvate kinase

activator: F-2,6-bP, AMP

inhibitor: Acetyl-CoA, ATP

24

In regards to the bisphosphoglycerate pathway in erythrocytes, bisphosphoglycerate mutase forms 2-3 BPG which binds to ___, decreasing its affinity for ___

Hb; O2

25

In liver, kidney, and intestine, fructokinase phosphorylates fructose to fructose-1-phosphate. Diabetic patients can clear fructose because they are not affected by ____

insulin

26

Galctosemia is the result of a lack of what enzyme?

galactose-1-phosphate uridyltransferase

27

Fructose, Galactose, and Mannose enter the ____ pathway for metabolism

glycolytic