Cellular Cellular RespirationRespirationCHAPTER 7CHAPTER 7

When is ATP Made in the Body?When is ATP Made in the Body?During a Process called During a Process called

Cellular RespirationCellular Respiration that takes place in that takes place in both both Plants & AnimalsPlants & Animals

What Does ATP Do for You?What Does ATP Do for You?It supplies YOU withIt supplies YOU with ENERGY!ENERGY!

Cellular RespirationCellular Respiration Includes pathways that require Includes pathways that require

oxygenoxygen Glucose is Glucose is oxidizedoxidized and O and O22 is is reducedreduced Glucose breakdown is therefore an Glucose breakdown is therefore an

oxidation-reductionoxidation-reduction reaction reaction Breakdown of one glucose results in Breakdown of one glucose results in

36 to 38 ATP36 to 38 ATP molecules molecules

Cellular RespirationCellular Respiration

• Cellular respiration – the complex process in Cellular respiration – the complex process in which cells make ATP by breaking down which cells make ATP by breaking down organic compounds.organic compounds.

What are the Stages of Cellular What are the Stages of Cellular Respiration?Respiration?

GlycolysisGlycolysisThe Krebs CycleThe Krebs CycleThe Electron Transport ChainThe Electron Transport Chain

Where Does Cellular Respiration Where Does Cellular Respiration Take Place?Take Place?

It actually takes It actually takes place in two place in two parts of the cell:parts of the cell:

Glycolysis Glycolysis occurs in the occurs in the CytoplasmCytoplasm

Krebs Cycle Krebs Cycle & ETC Take& ETC Take

place in the place in the MitochondriaMitochondria

Review of Mitochondria Structure

SmoothSmooth outer outer MembraneMembrane

FoldedFolded inner inner membranemembrane

Folds called Folds called CristaeCristaeSpace inside cristae Space inside cristae

called the called the MatrixMatrix

Step 1 of cellular respirations Glycolysis

Takes place in the Takes place in the CytoplasmCytoplasm

Anaerobic Anaerobic (Doesn’t Use (Doesn’t Use Oxygen)Oxygen)Requires input of Requires input of 2 ATP2 ATP

Glucose split into two Glucose split into two molecules of molecules of PyruvatePyruvate or or Pyruvic AcidPyruvic Acid

•Also produces Also produces 2 NADH and 4 ATP2 NADH and 4 ATP•Pyruvate is oxidized to Pyruvate is oxidized to Acetyl CoAAcetyl CoA

GLYCOLYSISGLYCOLYSIS

After glycolysis…After glycolysis…

• Once the glucose has been broken down into Once the glucose has been broken down into pyruvic acid, one of two things can happen…pyruvic acid, one of two things can happen…

• 1. if there is oxygen present = 1. if there is oxygen present = aerobic respirationaerobic respiration• 2. if there is NO oxygen present 2. if there is NO oxygen present

= = fermentationfermentation

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FermentationFermentation Occurs when Occurs when OO22 NOT present NOT present (anaerobic)(anaerobic)

Called Called Lactic AcidLactic Acid fermentation in fermentation in muscle cells muscle cells (makes (makes muscles muscles tired)tired)

Called Called Alcoholic Alcoholic fermentationfermentation in in yeast (produces yeast (produces ethanolethanol))

FermentationFermentation

Aerobic vs. AnaerobicAerobic vs. Anaerobic

Aerobic respirationAerobic respiration• Second stage of cellular respiration.Second stage of cellular respiration.

• In most cells glycolysis does not result in In most cells glycolysis does not result in fermentation. Instead when oxygen is available, fermentation. Instead when oxygen is available, pyruvic acid that was produced in glycolysis pyruvic acid that was produced in glycolysis undergoes aerobic respiration. undergoes aerobic respiration.

• Aerobic respiration takes place in the mitochondria. Aerobic respiration takes place in the mitochondria.

• Can be divided into two steps:Can be divided into two steps:1.1. Krebs CycleKrebs Cycle2.2. Electron Transport ChainElectron Transport Chain

Krebs Cycle SummaryKrebs Cycle SummaryRequires Oxygen (Aerobic)Requires Oxygen (Aerobic)Cyclical series of oxidation reactions that give Cyclical series of oxidation reactions that give

off off COCO22 and produce and produce one ATP per cycleone ATP per cycleTurns Turns twicetwice per glucose molecule per glucose moleculeProduces Produces two ATPtwo ATP Takes place in Takes place in matrix of mitochondriamatrix of mitochondriaAlso produces NADH & FADH2 (The red bulls)Also produces NADH & FADH2 (The red bulls)

Basically it just shuffles carbon around to give Basically it just shuffles carbon around to give off carbon dioxideoff carbon dioxide

Krebs CycleKrebs Cycle

Electron Transport Chain Electron Transport Chain SummarySummary

Uses NADH & FADH2 from krebs cycleUses NADH & FADH2 from krebs cycle34 ATP34 ATP Produced ProducedHH22OO Produced ProducedOccurs Across Occurs Across Inner Mitochondrial Inner Mitochondrial

membranemembrane

Electron Transport Chain Animation

Concept map