1 cellular respiration. 2 catabolic, exergonic, oxygen (o 2 ) energy macromolecules (glucose)energy...

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Cellular Cellular RespirationRespiration

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Cellular RespirationCellular Respiration

A catabolic, exergonic, oxygen (Ocatabolic, exergonic, oxygen (O22)) requiring process that uses energyenergy extracted from macromolecules (glucose)macromolecules (glucose) to produce energy (ATP)energy (ATP) and water (Hwater (H22O).O).

C6H12O6 + 6O2 6CO2 + 6H2O + energyglucoseglucose ATP

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Question:Question: In what kinds organisms does In what kinds organisms does

cellular respiration take place?cellular respiration take place?

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Plants and AnimalsPlants and Animals

Plants - AutotrophsPlants - Autotrophs: self-producers. Animals - Heterotrophs: consumers.

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MitochondriaMitochondria OrganelleOrganelle where cellular respirationcellular respiration takes

place.

Innermembrane

Outermembrane

Innermembrane space

MatrixCristae

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Redox ReactionRedox Reaction

Transfer of one or more electrons from one reactant to another.

Two types:Two types:

1.1. OxidationOxidation

2.2. ReductionReduction

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Oxidation ReactionOxidation Reaction

The lossloss of electrons from a substance.

Or the gaingain of oxygenoxygen.

C6H12O6 + 6O2 6CO2 + 6H2O + energy

glucose ATP

OxidationOxidation

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Reduction ReactionReduction Reaction

The gaingain of electrons to a substance.

Or the lossloss of oxygenoxygen.

glucose ATP

C6H12O6 + 6O2 6CO2 + 6H2O + energy

ReductionReduction

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Breakdown of Cellular Breakdown of Cellular RespirationRespiration

Four main parts (reactions).Four main parts (reactions).

1. Glycolysis (splitting of sugar)1. Glycolysis (splitting of sugar)a. cytosol, just outside of

mitochondria.

2. Grooming Phase2. Grooming Phasea. migration from cytosol to matrix.

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Breakdown of Cellular Breakdown of Cellular RespirationRespiration

3. Krebs Cycle (Citric Acid Cycle)3. Krebs Cycle (Citric Acid Cycle)a. mitochondrial matrix

4. Electron Transport Chain (ETC) 4. Electron Transport Chain (ETC) andand

Oxidative PhosphorylationOxidative Phosphorylationa. Also called Chemiosmosisb. inner mitochondrial membrane.

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1. Glycolysis1. Glycolysis

Occurs in the cytosol just outside of mitochondria.

Two phases (10 steps):Two phases (10 steps):

A. Energy investment phaseA. Energy investment phasea. Preparatory phase (first 5

steps).

B. Energy yielding phaseB. Energy yielding phasea. Energy payoff phase (second 5

steps).

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1. Glycolysis1. Glycolysis

A. Energy Investment Phase:A. Energy Investment Phase:

Glucose (6C)

Glyceraldehyde phosphate (2 - 3C) (G3P or GAP)

2 ATP - used0 ATP - produced0 NADH - produced

2ATP

2ADP + P

C-C-C-C-C-C

C-C-C C-C-C

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1. Glycolysis1. Glycolysis

B. Energy Yielding PhaseB. Energy Yielding Phase

Glyceraldehyde phosphate (2 - 3C) (G3P or GAP)

Pyruvate (2 - 3C) (PYR)

0 ATP - used4 ATP - produced2 NADH - produced

4ATP

4ADP + P

C-C-C C-C-C

C-C-C C-C-C

GAP GAP

(PYR) (PYR)

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1. Glycolysis1. Glycolysis

Total Net YieldTotal Net Yield

2 - 3C-Pyruvate (PYR)2 - ATP (Substrate-level Phosphorylation)2 - NADH

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Substrate-Level Phosphorylation

ATP is formed when an enzyme transfers a phosphate groupphosphate group from a substrate to ADP.

Enzyme

Substrate

O-

C=OC-O-CH2

P P P Adenosine

ADP(PEP)Example:

PEP to PYR

P PP

ATP

O-

C=OC=OCH2

Product(Pyruvate)

Adenosine

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Fermentation Fermentation

Occurs in cytosol when “NO Oxygen”“NO Oxygen” is present (called anaerobic).(called anaerobic).

Remember: glycolysisglycolysis is part of fermentationfermentation.

Two Types:Two Types:

1.1. Alcohol FermentationAlcohol Fermentation

2. Lactic Acid Fermentation2. Lactic Acid Fermentation

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Alcohol FermentationAlcohol Fermentation

Plants and FungiPlants and Fungi beer and beer and winewine

glucose

Glycolysis

CCCCCC

CCC

2 Pyruvic acid

2ATP2ATP2ADP+ 2

2NADH

P

2 NAD+

CC

2 Ethanol2 Ethanol2CO2CO22

releasedreleased

2NADH 2 NAD+

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Alcohol FermentationAlcohol Fermentation

End Products: Alcohol fermentationEnd Products: Alcohol fermentation

2 - ATP (substrate-level phosphorylation)

2 - CO2

2 - Ethanol’s

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Lactic Acid FermentationLactic Acid Fermentation

Animals (pain in muscle after a Animals (pain in muscle after a workout).workout).

2 Lactic2 Lactic acidacid

2NADH 2 NAD+

CCC

Glucose

GlycolysisCCC

2 Pyruvic acid

2ATP2ATP2ADP+ 2

2NADH

P

2 NAD+

CCCCCC

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Lactic Acid FermentationLactic Acid Fermentation

End Products: Lactic acid End Products: Lactic acid fermentationfermentation

2 - ATP (substrate-level phosphorylation)

2 - Lactic Acids

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2. Grooming Phase2. Grooming Phase

Occurs when Oxygen is present (aerobic).Oxygen is present (aerobic).

2 Pyruvate (3C) molecules are transported through the mitochondria membrane to the matrix and is converted to 2 Acetyl CoA (2C) molecules.

CytosolCCC

2 Pyruvate

2 CO2 CO22

2 Acetyl CoA2 Acetyl CoAC-CC-C

2NADH2NADH2 NAD+

Matrix

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2. Grooming Phase2. Grooming Phase

End Products: End Products: grooming phasegrooming phase

2 - NADH2 - NADH

2 - CO2 - CO22

2- Acetyl CoA (2C)2- Acetyl CoA (2C)

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3. Krebs Cycle (Citric Acid 3. Krebs Cycle (Citric Acid Cycle)Cycle)

Location:Location: mitochondrial matrix.

Acetyl CoA (2C) bonds to Oxalacetic acid (4C - OAA) to make Citrate (6C).

It takes 2 turns of the krebs cycle to oxidize 1 glucose molecule.

MitochondrialMatrix

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3. Krebs Cycle (Citric Acid 3. Krebs Cycle (Citric Acid Cycle)Cycle)

KrebsCycle

1 Acetyl CoA (2C)

3 NAD+

3 NADH3 NADHFAD

FADHFADH22

ATPATP ADP + P

(one turn)(one turn)

OAA (4C) Citrate (6C)

2 CO2

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3. Krebs Cycle (Citric Acid 3. Krebs Cycle (Citric Acid Cycle)Cycle)

KrebsCycle

2 Acetyl CoA (2C)

6 NAD+

6 NADH6 NADH2 FAD

2 FADH2 FADH22

2 ATP2 ATP 2 ADP + P

(two turns)(two turns)

OAA (4C)Citrate (6C)

4 CO2

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3. Krebs Cycle (Citric Acid 3. Krebs Cycle (Citric Acid Cycle)Cycle) Total net yield (2 turns2 turns of krebs

cycle)

1. 2 - ATP (substrate-level phosphorylation)

2. 6 - NADH3. 2 - FADH2

4. 4 - CO2

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4. Electron Transport Chain (ETC) 4. Electron Transport Chain (ETC) andand Oxidative Phosphorylation Oxidative Phosphorylation ((ChemiosmosisChemiosmosis))

Location:Location: inner mitochondrial membrane.

Uses ETC (cytochrome proteins)ETC (cytochrome proteins) and ATP Synthase (enzyme) to make ATP.

ETC pumps H+ (protons) across innermembrane (lowers pH in innermembrane space).Inner

MitochondrialMembrane

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4. Electron Transport Chain (ETC) 4. Electron Transport Chain (ETC) andand Oxidative Phosphorylation Oxidative Phosphorylation ((ChemiosmosisChemiosmosis))

The H+ then move via diffusiondiffusion (Proton Motive Force) through ATP Synthase to make ATP.

All NADH and FADH2 converted to ATP during this stage of cellular respirationcellular respiration.

Each NADH converts to 3 ATP.

Each FADH2 converts to 2 ATP (enters the ETC at a lower level than NADH).

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4. Electron Transport Chain (ETC) 4. Electron Transport Chain (ETC) andand Oxidative Phosphorylation Oxidative Phosphorylation ((ChemiosmosisChemiosmosis))

Innermembrane

Outermembrane

Innermembrane space

MatrixCristae

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4. 4. ETC and Oxidative Phosphorylation ETC and Oxidative Phosphorylation ((Chemiosmosis for Chemiosmosis for NADHNADH))

NADH+ H+

ATPSynthase

1H+ 2H+ 3H+

higher Hhigher H++

concentrationconcentration

H+

ADP + ATP

lower Hlower H++

concentrationconcentration

H+

(Proton Pumping)

P

E T C

NAD+

2H+ + 1/2O2 H2O

Intermembrane SpaceIntermembrane Space

MatrixMatrix

InnerMitochondrialMembrane

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4. 4. ETC ETC and and Oxidative Phosphorylation Oxidative Phosphorylation (Chemiosmosis for (Chemiosmosis for FADH2)

FADH2

+ H+

ATPSynthase

1H+ 2H+

higher Hhigher H++

concentrationconcentration

H+

ADP + ATP

lower Hlower H++

concentrationconcentration

H+

(Proton Pumping)

P

E T C

FAD+2H+ +

1/2O2

H2O

Intermembrane SpaceIntermembrane Space

MatrixMatrix

InnerMitochondrialMembrane

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TOTAL ATP YIELDTOTAL ATP YIELD

1. 04 ATP - substrate-level phosphorylation

2. 34 ATP - ETC & oxidative phosphorylation

38 ATP - TOTAL YIELD

ATPATP

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Eukaryotes(Have Membranes)

Total ATP Yield02 ATP - glycolysis (substrate-level phosphorylation)

04 ATP - converted from 2 NADH - glycolysis

06 ATP - converted from 2 NADH - grooming phase

02 ATP - Krebs cycle (substrate-level phosphorylation)

18 ATP - converted from 6 NADH - Krebs cycle

04 ATP - converted from 2 FADH2 - Krebs cycle

36 ATP - TOTAL

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Maximum ATP Yield for Cellular Respiration (Eukaryotes)

36 ATP (maximum per glucose)

Glucose

Glycolysis

2ATP 4ATP 6ATP 18ATP 4ATP 2ATP

2 ATP(substrate-levelphosphorylation)

2NADH

2NADH

6NADH

KrebsCycle

2FADH2

2 ATP(substrate-levelphosphorylation)

2 Pyruvate

2 Acetyl CoA

ETC and Oxidative Phosphorylation

Cytosol

Mitochondria

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ProkaryotesProkaryotes(Lack Membranes)(Lack Membranes)

Total ATP Yield02 ATP - glycolysis (substrate-level phosphorylation)

06 ATP - converted from 2 NADH - glycolysis

06 ATP - converted from 2 NADH - grooming phase

02 ATP - Krebs cycle (substrate-level phosphorylation)

18 ATP - converted from 6 NADH - Krebs cycle

04 ATP - converted from 2 FADH2 - Krebs cycle

38 ATP - TOTAL

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Question:Question: In addition to glucose, what other In addition to glucose, what other

various food molecules are use in various food molecules are use in Cellular Respiration?Cellular Respiration?

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Catabolism of VariousCatabolism of VariousFood MoleculesFood Molecules Other organic molecules used for

fuel.

1. Carbohydrates: polysaccharides

2. Fats: glycerol’s and fatty acids

3. Proteins: amino acids

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