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Flashcards in Cellular Respiration Deck (57)
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1

Organisms store glucose as...

Glycogen or starch.

2

In cells, glucose is oxidized by...

A long series of redox reactions. The released free energy is used to synthesize ATP. Known as cellular respiration.

3

4 processes of cellular respiration

Glycolysis, pyruvate processing, citric acid cycle, and electron transport/oxidative phosphorylation.

4

Glycolysis

Sequence of enzyme catalyzed reaction by which glucose is converted into pyruvate.

5

What are the 4 enzymes in the 4 steps of the glycolysis prep phase?

Hexokinase, phosphohexose isomerase, phosphofructokinase-1, and aldolase.

6

What is produced at the end of the prep phase in glycolysis?

Glyceraldehyde 3-phosphate, dihydroxyacetone phosphate, and 2 ADP.

7

What are the 6 enzymes in the 6 steps of the glycolysis payoff phase?

Triose phosphate isomerase, glyceraldehyde 3-phosphate dehydrogenase, phosphoglycerate kinase, phosphoglycerate kinase, phosphoglycerate mutase, enolase, and pyruvate kinase.

8

What is produced at the end of glycolysis?

2 pyruvate, 2 NADH, 2 H, 2 H2O and 2 ATP.

9

Tautomerization

Effectively lowers the concentration of the reaction product, drives reaction towards ATP formation.

10

How is glycolysis regulated?

Feedback inhibition. High levels of ATP inhibit the third enzyme, phosphofructokinase.

11

What happens to phosphofructokinase when there is too much ATP?

Phosphofructokinase has two binding sites for ATP; when ATP binds the the active site the reaction continues, when ATP levels are too high, it will bind the regulatory site and inhibits the enzyme

12

Substrate-level phosphorylation

Occurs when ATP is produced by the enzyme-catalyzed transfer of a phosphate group from an intermediate substrate to ADP. How ATP is produced in glycolysis and the citric acid cycle.

13

What is used in glycolysis (consumed)?

1 glucose, 2 ATP, 2 NAD+

14

What is produced in glycolysis?

2 pyruvate, 4 ATP, 2 NADH

15

Net amount of ATP production at the end of glycolysis

2 ATP

16

Fates of pyruvate

Anaerobic conditions (fermentation) or aerobic conditions (citric acid cycle).

17

Cristae

Extensions of the inner mitochondrial membrane.

18

Mitochondrial matrix

Inside the inner mitochondrial membrane.

19

Where does pyruvate processing take place?

Enzyme complex called pyruvate dehydrogenase in mitochondrial matrix (eukaryotes).

20

What are the series of reactions that pyruvate undergoes?

One of its carbon's is oxidized to CO2, NADH is produced, and the remaining two carbon unit is attached to coenzyme A producing acetyl CoA.

21

What does thiamine deficiency result in

In sufficient pyruvate dehydrogenase activity.

22

What are the 8 enzymes of the citric acid cycle?

Citrate synthase, aconitase, isocitrate dehydrogenase, alpha ketongluatarate dehydrogenase, succinyl-coA sythetase, succinate dehyrdogenase, fumarase, malate dehydrogenase

23

What is the net results of the citric acid cycle?

2 CO2, 3 NADH, FADH2, GTP, CoA, 3 H+

24

Amphibolic

Relates to both catabolism and anabolism.

25

Glucose is completely oxidized to CO2 by...

Glycolysis, pyruvate processing, and the citric acid cycle

26

As glucose is oxidized, free energy becomes...

More negative

27

For each molecule of glucose that is oxidized, the cell produces...

6 CO2, 4 ATP, 10 NADH, and 2 FADH2.

28

What happens to the reduced electron carriers after glucose oxidation?

NAD+ is a reduced electron carrier in glucose oxidiation because it is used to accept the electrons. FADH is used as well. NADH and FADH2 (the reduced form) moved to the electron transport chain donates a pair of electrons. Electrons are ultimately transferred to oxygen to form water.

29

Where do NADH and FADH2 get oxidized?

In the inner membrane of the mitochondria, the electron transport chain.

30

Ubiquinone (coenzyme Q)

Lipid-soluble, non-proteins part of the ETC.