BIOLK101 - Chapter 9 Cellular Respiration, Fermentation, Proton Gradient

oxidation

losing an electron

reduction

gaining an electron

what is being oxidized in cellular respiration

glucose (losing H)

what is being reduced in cellular respiration

oxygen (gaining a H)

4 stages of cellular respiration

glycolysis

acetyl CoA

Krebs cycle

electron transport chain

yield of glycolysis

2 pyruvate + 2 ATP

yield of acetyl CoA

2 NADPH + 2 CO2

yield of krebs cycle

6 NADH, 2 FADH2, 2 ATP, 4 CO2

yield of electron transport chain

around 30 ATP

mitochondria

double membrane structure that helps with ATP production

NAD+

electron shuttle that accepts H+ and shuttles it to mitochondrial electron transport chaing for ATP production

matrix

cyctoplasm of mitochondria

glycolysis

glucose splitting into 2 pyruvate and 2 ATP

where does glycolysis happen?

cytosol

1. glucose

needs ATP, glucose 6 phosphate

hexokinase

transfer phosphate from ATP to glucose to form glucose 6 phosphate

phosphoglucoisomerase

glucose 6 phosphate to fructose 6 phosphate

2. glucose 6 phosphate

fructose 6 phosphate

3. fructose 6 phosphate

needs ATP, fructose 1,6 biphosphate

phosphfructokinase

turn fructose 6 phosphate to fructose 1, 6 biphosphate

4. fructose 1,6 biphosphate

glyceraldehyde 3 phosphate (G3P) and dihydroxy acetone phosphate with isomerase

aldolase

turn fructose into G3P/di hydroxy acetone phosphate

isomerase

turn G3P into dihydroxy acetone phosphate (or vice versa)

Type of reaction: making of G3P

Endergonic (needs ATP)

5. G3P

makes 2 NADH, 1-3 biphosphate glycerate

triose phosphate dehydrogenase

G3P to 1-3 biphosphate glycerate

6. 1-3 biphosphate glycerate

release 2 ATP

3 phosphate glycerate

phosphoglycerokinase

1-3 biphosphate glycerate to 3 phosphate glycerate

7. 3 phosphate glycerate

2 phosphate glycerate

phosphoglyceromutase

3 phosphate glycerate to 2 phosphate glycerate

8. 2 phosphate glycerate

release water, phosphoenol pyruvate

enolase

2 phosphate glycerate to phosphoenol pyruvate

9. phosphoenol pyruvate

release 2 ATP, PYRUVATE!

pyruvate kinase

phosphoenol pyruvate to pyruvate

hexokinase

transfer P from ATP to glucose

phosphofructokinase

transfer P to F6F to make F1,6 biphosphate

phosphoglycerokinase

form 2 ATP by substrate level phosphorylation

pyruvate kinase

form ATP

CoA overall reaction

2 pyruvate —> 2 Acetyl CoA + 2 CO2 + 2 NADH

oxidative decarboxylation

making of Acetyl CoA

where does CoA occur?

matrix of mitochondria

Pyruvate dehydrogenase complex deficiency

congenital infantile lactic acidosis

PPCD

genital change causing conversion between pyruvate to CoA to be impaired

Krebs cycle

getting NADH and FADH2

Where does the Krebs Cycle occur?

mitochondrial matrix

Krebs Cycle overal reaction

2 acetyl CoA —> 4 CO2 + 6 NADH + 6 H+ + 2 FADH2 + 2 ATP

8 enzymes of Krebs Cycle

acetyl coA

citrate

isocitrate

alpha ketoglutarate

succinyl CoA

succinate

fumarate

malate

oxaloacetate

what does the isocitrate —> alpha ketoglutarate release?

2 CO2 and 2 NADH

what does the alpha ketoglutarate to succinyl CoA release

2 CO2 and 2 NADH

what does succinyl CoA —> succinate release

GTP (ATP)

what does succinate —> fumarate release

2 FADH2

what does malate —> oxaloacetate release?

2 NADH

electron transport chain/chemiosmosis

energy from electron transport chain transfers H+ into membrane space

photosystem IV

form H2O, pump H+ out

Net equation of making water

4 h+ + 4 e- + O2 —> 2 H2O

Photosystem I

NADH —> NADH+

Photosystem II

FADH —> FAD+

intermembrane space

low pH

Oxygen

final electron acceptor, accept electrons after ATP is made

Wat happens without O2?

nothing to accept electrons = cummulation of e- = no flow of H+

substrate level phosphorylation

ATP formed from phosphorylated substrate

oxidative phosphorylation

happens in chemiosmosis, ATP synthase

stator

hold knob stationary while it’s rotating to make ATP

rotator (oxidative phosphorylation)

spins H+ into matrix

stalk (oxidative phosphorylation)

spins/activate catalytic site

3 catalytic site in knob (oxidative phosphorylation)

produce ATP

anaerobic respiration

no oxygen present during respiration

fermentation - anaerobic respiration

ethanol, lactate, other products in cytosol

NAD+

normally regenerated with O2, cannot form more ATP if you don’t have NAD+

5 dehydrogenases of Krebs Cycle

Isocitrate

Dehydrogenase,

a-Ketoglutarate Dehydrogenase,

Succinate Dehydrogenase,

Malate Dehydrogenase