cellular respiration. a quick review… a quick review… when we eat, we get ______ from glucose...

Cellular RespirationCellular Respiration


A quick review…A quick review…

When we eat, we get ______ from When we eat, we get ______ from glucose and other sugarsglucose and other sugars

Food energy is c_______ into usable Food energy is c_______ into usable energyenergy

Energy used to bond phosphate Energy used to bond phosphate groups to ADP to make _____ .groups to ADP to make _____ .


What is cell respiration???What is cell respiration???

Respiration:Respiration: the process of breaking the process of breaking down food molecules into usable energydown food molecules into usable energy

THE GOAL:THE GOAL: Create ATP for cells to useCreate ATP for cells to use Free up electrons—have high energyFree up electrons—have high energy

C6H12O6 + 6 O2 → 6 CO2 + 6 H2O + Energy (ATP + heat)

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Types of cell respirationTypes of cell respiration

Aerobic Processes:Aerobic Processes: REQUIREREQUIRE oxygen to take place oxygen to take place A lot of energy available (efficient) A lot of energy available (efficient)

Anaerobic Processes:Anaerobic Processes: DO NOTDO NOT require oxygen to take place require oxygen to take place Get energy quickly (inefficient)Get energy quickly (inefficient)


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GlycolysisGlycolysis Involves breaking down 6-carbon Involves breaking down 6-carbon

sugarssugars Break sugars into pyruvic acid moleculesBreak sugars into pyruvic acid molecules

3-Carbon molecules3-Carbon molecules

This process is This process is ANAEROBICANAEROBIC No oxygen necessaryNo oxygen necessary

Occurs in the cytoplasm of cellsOccurs in the cytoplasm of cells

GlycolysisGlycolysis You will need to know this…You will need to know this…

GlycolysisGlycolysis

Just Kidding… Just Kidding…

GlycolysisGlycolysis Glycolysis also creates hydrogen ions Glycolysis also creates hydrogen ions

and free electronsand free electrons The whole point of respiration = high energyThe whole point of respiration = high energy

H H ++ ions bond with NAD ions bond with NAD++ to form to form NADH + H NADH + H ++

NADH carries electrons and H NADH carries electrons and H ++ ions ions

This process uses This process uses 2 ATP 2 ATP but but creates creates 4 ATP4 ATP molecules molecules

GlycolysisGlycolysis TOTAL ATP PRODUCTION:TOTAL ATP PRODUCTION:

Glycolysis Glycolysis Step 1Step 1 uses 2 ATP molecules uses 2 ATP molecules

Glycolysis Glycolysis Step 2Step 2 converts 4 ADP converts 4 ADP molecules into 4 ATP moleculesmolecules into 4 ATP molecules

Net ATP production = 2 ATP for every Net ATP production = 2 ATP for every glucose glucose

moleculemolecule


Oxygen is our Oxygen is our friend…friend…

When oxygen is When oxygen is present, present, aerobic aerobic respirationrespiration occurs occurs

Happens in the Happens in the mitochondriamitochondria

GlycolysisGlycolysis Breaking down Pyruvic Acid…Breaking down Pyruvic Acid…

Occurs in the mitochondriaOccurs in the mitochondria

Pyruvic Acid = 3-carbon compoundPyruvic Acid = 3-carbon compound

Broken down into…Broken down into… 2-Carbon compound—acetic acid2-Carbon compound—acetic acid Carbon DioxideCarbon Dioxide

GlycolysisGlycolysis Intermediate Step in GlycolysisIntermediate Step in Glycolysis

2-Carbon Compound—Acetic Acid2-Carbon Compound—Acetic Acid Combined with coenzyme A (CoA)Combined with coenzyme A (CoA) Forms compound called acetyl-CoAForms compound called acetyl-CoA

This is only an intermediate step—have This is only an intermediate step—have to move pyruvic acid into Krebs Cycleto move pyruvic acid into Krebs Cycle


Glycolysis =2 ATP


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Citric Acid (Krebs) CycleCitric Acid (Krebs) Cycle

Produces more ATP and releases Produces more ATP and releases more electronsmore electrons Electrons picked up by NAD Electrons picked up by NAD ++ and FAD and FAD

Organic carrier moleculesOrganic carrier molecules

Occurs inside mitochondriaOccurs inside mitochondria Mitochondrial MatrixMitochondrial Matrix


Acetyl CoA combines with a 4-carbon Acetyl CoA combines with a 4-carbon molecule to form a 6-carbon moleculemolecule to form a 6-carbon molecule

Citric AcidCitric Acid

NAD becomes NADH NAD becomes NADH FADH becomes FADHFADH becomes FADH22

COCO22 released released ATP is createdATP is created

The cycle starts againThe cycle starts again

Citric Acid Cycle =

2 ATP



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Electron Transport ChainElectron Transport Chain What is the ETC???What is the ETC???

A series of molecules along which A series of molecules along which electrons are transferred, releasing electrons are transferred, releasing energyenergy

Occurs in the mitochondria—Occurs in the mitochondria— mitochondrial matrix mitochondrial matrix

Aerobic processAerobic process Oxygen is involvedOxygen is involved

Acts as the electron acceptorActs as the electron acceptor

Electron Transport ChainElectron Transport Chain

As the electrons are passed between As the electrons are passed between carrier proteins, energy is releasedcarrier proteins, energy is released ATP is createdATP is created

Carbon is given off as carbon dioxideCarbon is given off as carbon dioxide

Electron Transport ChainElectron Transport Chain

ETC =34 ATP

Electron Transport ChainElectron Transport Chain A problem exists if there is no oxygenA problem exists if there is no oxygen

Anaerobic processAnaerobic process

When oxygen is used up, electrons When oxygen is used up, electrons cannot be removedcannot be removed

Traffic jam in the mitochondriaTraffic jam in the mitochondria

KEY POINTKEY POINT —Electron Transport —Electron Transport Chain Chain cannot run without cannot run without oxygenoxygen

Anaerobic RespirationAnaerobic Respiration If no oxygen present after glycolysis, If no oxygen present after glycolysis,

pyruvic acid can still be broken downpyruvic acid can still be broken down This is FermentationThis is Fermentation

Only 2 ATP made during fermentationOnly 2 ATP made during fermentation

Uses electrons carried by NADH + HUses electrons carried by NADH + H ++

so that NADso that NAD++ can regenerate for can regenerate for glycolysisglycolysis

Anaerobic RespirationAnaerobic Respiration

Anaerobic RespirationAnaerobic Respiration ****Two types of fermentationTwo types of fermentation

Lactic Acid FermentationLactic Acid Fermentation

Alcoholic FermentationAlcoholic Fermentation (Yeast) (Yeast)

Glucose2 Pyruvic

Acid2 Lactic

Acid

Glucose2 Pyruvic

Acid2 Ethanol + 2 CO2

Anaerobic RespirationAnaerobic Respiration Lactic Acid FermentationLactic Acid Fermentation

Muscle fatigueMuscle fatigue When your muscle cells require more energy When your muscle cells require more energy

than can be producedthan can be produced Lack of oxygenLack of oxygen Lactic acid build up = muscle fatigueLactic acid build up = muscle fatigue

When oxygen is present, lactic acid breaks When oxygen is present, lactic acid breaks downdown

Anaerobic RespirationAnaerobic Respiration Alcohol FermentationAlcohol Fermentation

Occurs in bacteria, plants and most Occurs in bacteria, plants and most animalsanimals

Can you think of a bacteria that is used Can you think of a bacteria that is used for fermentation???for fermentation???

Pyruvic Acid is converted into ethanol Pyruvic Acid is converted into ethanol and carbon dioxideand carbon dioxide


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General FormulaGeneral Formula

C6H12O6 + 6 O2 6 CO2 + 6 H2O

Often, in attempts to simplify, false paradigms are created.

Some textbooks do this when introducing biochemical reactions.

Photosynthesis

Respiration

26126222 OOHCOHCOlightOH

261262 COOHCOlight

22261262 COATPOHOOHCOH

WEGWEG

226126 COATPOOHC

cellular respiration. a quick review… a quick review… when we eat, we get ______ from glucose...

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mitochondriapyruvic

atp moleculesglycolysis

carbon compoundbroken

oxygen present

nadh h nadh

friendwhen oxygen

carbon sugarsbreak sugars

carbon moleculecitric