Glycolysis, CAC, and ETC (oxidative phosphorylation) Flashcards Preview

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Flashcards in Glycolysis, CAC, and ETC (oxidative phosphorylation) Deck (33):
1

what are the two stages of glycolysis

1. preparatory-phosphorylation
2. Payoff- REDOX or electron transfer

2

What is the net products of glycolyisis

2 pyruvate, 2ATP and 2 NADH+H

3

T/F all dietary carbohydrates are broken down to glucose

False

4

Where does Galactose enter glycolysis

glucose-1-phosphate

5

where do mannose and fructose enter glycolysis

fructose-6-phosphate

6

Regulation of PFK-1

ADP and AMP activate
ATP and citrate deactivate

7

The pentose phosphate pathway products

Glucose-6-phosphate are oxidized into ribose sugars while making:
NADPH and Ribose sugars (nucleotides, ATP, FAD, Coenzyme A, NAD+)

8

Why is NADPH important

necessary for reductive biosynthesis (creating fatty acids and sterols) and free radical protection, and must be maintained within the cell.

9

Regulation of pentose phosphate pathway

NADPH will inhibit glucose-6-phosphate from becoming 6-phosphogluconolactone and prevent more NADPH from being made

10

3 fates of pyruvate

1. Fermentation by microbes into ethanol and CO2 (anaerobic)
2. enter the CAC by Acetyl-CoA (aerobic)
3. Fermentation in humans into lactate (anaerobic)

11

Why is fermentation important?

it regenerates the NAD+ so that glycolysis can occur in the absence of oxygen.
Lactate is readily transported out of the cells and into the blood, then it enters the liver where is is converted into glucose via gluconeogenesis (cori cycle).

12

Mitochondria outer membrane

freely permeable to small molecules and ions

13

Mitochondria inner membrane

impermeable to most small molecules and ions including H. Has ETC proteins and ATPsynthase

14

Mitochondria matrix

contains pyruvate dehydrogenase complex
CAC enzymes
Fatty acid beta oxidation
AA oxidation
DNA ribosomes

15

How is mitochondria dysfunction tied to apoptosis

release of cytochrome c moves to cytosol. assemble apoptosome which leads to capsase cascade which leads to cell death.

16

what enzyme converts pyruvate to Acetyl Co-A

pyruvate dehydrogenase complex(requries five vitamins)
also gives off NADH+H
it is in the matrix of the mitochondria

17

Citric acid cycle products

per turn you get:
3 NADH
2 CO2
1 GTP or ATP
1 FADH2
*two turns per glucose and requires oxygen indirectly*

18

Pyruvate dehyrdogenase complex allosteric redulators

inhibition: ATP, acetyl-CoA, NADH, and FAs
activation: AMP, CoA, NAD+, and Calcium

19

The CAC is regulated allosterically how?

-energy substrates/products allosterically regulate enzymes
-regulated at the most exergonic steps
-Mass action ratio
[NADH]/[NAD+]
[ATP]/[ADP]
oxaloacetate

20

Three electron transfer types

1. Direct electron transfer
2. Hydrogen atom
3. Hydride ion

21

Unbiquinone

can carry both electrons and protons
lipid soluble and membrane mobile

22

cytocrhromes

only accepts electrons
type c is mobile

23

Iron-sulfur proteins

only accepts electrons

24

Complex I aka NADH dehydrogenase

NADH+H is oxidized and the electrons are passed along iron-sulfur proteins to a quinone complex and the hydrogens are sent to the intermembrane space

25

Complex II aka Succinate dehydrogenase

FADH2 is oxidized and the electron are passed to a reduced quinone complex

26

Complex III aka cytochrome bc complex

cytochrome c is reduced by ubiquinone and hydrogens are released into the inter membrane space
-this stage free radical ubiquinones are made but are then reduced
-hydrogen ions are pumped out

27

Complex IV aka cytochrome oxidase

cytochrome c is oxidized here and oxygen is the final electron acceptor. 4 hydrogens are also pumped out
-cytochrome c is the final carrier of electrons

28

ATP synthase

4 hydrogens/ATP
2.5 ATP per NADH
1.5 ATP per FADH2

29

How is ATP transported out of the mitochondria?

via adenine nucleotide translocase (antiporter) ADP in ATP out

30

Malate-aspartate shuttle

this is in the liver, kidney, and heart.
The NADH from glycolysis used this shuttle to get into the matrix

31

Glycerol 3-phosphate shuttle

Brain and skeletal muscle
How NADH from glycolysis is brought into matrix from cytosol but it enters as FADH2 so it is less efficient

32

two conditions that favor ROS fromation

1. mitochondria not making ATP
lack of O2
Lack of ADP
2. Excess NADH

**NADPH reduce ROS**

33

How much ATP per glucose

32 ATP/glucose