Cellular Cellular RespirationRespirationWhere the fuel is burned.Where the fuel is burned.

MitochondriaMitochondria Double membrane bound Double membrane bound

organelle.organelle.

Outer membraneOuter membrane encloses encloses the entire structure.the entire structure.

Inner membraneInner membrane encloses encloses a fluid-filled a fluid-filled matrix.matrix.

Folded Folded cristae cristae project into project into the matrix. Increases the matrix. Increases surface areasurface area

Small circular Small circular DNA. DNA.

MitochondriaMitochondria It is the site of It is the site of cellular respirationcellular respiration, , a a catabolic, “breaking down”catabolic, “breaking down”, , Exergonic, “energy releasing”, Exergonic, “energy releasing”, Aerobic: “oxygenAerobic: “oxygen requiring”requiring” process process

that uses energy extracted fromthat uses energy extracted from glucose glucose to produceto produce ATPATP..

ATPATP Energy is released Energy is released

from ATP when a from ATP when a phosphatephosphate group is group is removedremoved..

ATPATP is changed to is changed to ADPADP. .

ADP can then be ADP can then be ““rechargedrecharged” to ATP ” to ATP again. again.

Overall Reaction:Overall Reaction:

CC66HH1212OO66 + 6O + 6O22 → → 6CO 6CO22 + 6H + 6H22O + 36 ATP O + 36 ATP + Heat+ Heat

Do the products and reactants look Do the products and reactants look familiar?familiar?

Cellular Respiration Cellular Respiration OverviewOverview Breakdown of glucose begins in the Breakdown of glucose begins in the

cytoplasm, the liquid matrix inside of all cytoplasm, the liquid matrix inside of all cellscells

At this point life diverges into two forms At this point life diverges into two forms and two pathwaysand two pathways Anaerobic cellular respirationAnaerobic cellular respiration also called: also called:

fermentationfermentation Aerobic cellular respirationAerobic cellular respiration, commonly just , commonly just

called cellular respiration.called cellular respiration.

Stages of CellularStages of Cellular RespirationRespirationCellular Respiration can be broken Cellular Respiration can be broken down into three stages:down into three stages:

1.1. GlycolysisGlycolysis (splitting of sugar) (splitting of sugar)

2.2. Kreb’s CycleKreb’s Cycle also known as the also known as the Citric Acid Citric Acid CycleCycle

3.3. Electron Transport Chain (ETC) Electron Transport Chain (ETC) also called also called chemiosmosischemiosmosis

GlycolysisGlycolysis Occurs in the cytoplasm of all cellsOccurs in the cytoplasm of all cells

Series of reactions which break the Series of reactions which break the 6-6-carbon glucosecarbon glucose molecule down into molecule down into two 3-two 3-carbon molecules called pyruvate.carbon molecules called pyruvate.

Process is an ancient one-Process is an ancient one-all organisms all organisms from simple bacteria to humans perform from simple bacteria to humans perform it the same way.it the same way.

Yields 2 ATPYields 2 ATP molecules for every one molecules for every one glucose molecule broken downglucose molecule broken down

Yields 2 NADHYields 2 NADH per glucose molecule per glucose molecule

Aerobic Cellular Aerobic Cellular Respiration Respiration Oxygen required = aerobicOxygen required = aerobic 2 more sets of reactions which occur in a 2 more sets of reactions which occur in a

specialized structure within the cell called specialized structure within the cell called the the mitochondriamitochondria 1. Kreb’s Cycle1. Kreb’s Cycle 2. Electron Transport Chain2. Electron Transport Chain

Kreb’s Cycle

Kreb’s Cycle Kreb’s Cycle (Citric Acid Cycle)(Citric Acid Cycle) Occurs in the mitochondrial matrixOccurs in the mitochondrial matrix Completes the breakdown of glucoseCompletes the breakdown of glucose

Takes the pyruvate (3-carbons) and breaks it Takes the pyruvate (3-carbons) and breaks it down, the carbon and oxygen atoms end up in down, the carbon and oxygen atoms end up in COCO22 and H and H22OO

Hydrogens and electrons are stripped and Hydrogens and electrons are stripped and loaded onto NADloaded onto NAD++ and FAD to produce NADH and FAD to produce NADH and FADH2and FADH2

Production of only 2 more ATPProduction of only 2 more ATP but but loads up the coenzymes with Hloads up the coenzymes with H++ and and electrons which move to the 3electrons which move to the 3rdrd stage stage

Kreb’s Cycle

Electron Transport Chain Electron Transport Chain (ETC)(ETC)

Occurs along the Occurs along the inner mitochondrial inner mitochondrial membrane.membrane.

Electron carriers loaded with electrons and Electron carriers loaded with electrons and protons from the Kreb’s cycle move to this protons from the Kreb’s cycle move to this chain-like a series of steps (staircase).chain-like a series of steps (staircase).

As electrons drop down stairs, energy released As electrons drop down stairs, energy released to to form a total of 32 ATPform a total of 32 ATP

Oxygen waits at bottom of staircase, picks up Oxygen waits at bottom of staircase, picks up electrons and protons and in doing so becomes electrons and protons and in doing so becomes water. water. Cleans up the areaCleans up the area!! !!

Energy TallyEnergy Tally 36 ATP for aerobic vs. 2 ATP for anaerobic36 ATP for aerobic vs. 2 ATP for anaerobic

Glycolysis Glycolysis 2 ATP2 ATP

Kreb’s Kreb’s 2 ATP2 ATP

Electron TransportElectron Transport 32 ATP32 ATP 36 ATP36 ATP

Anaerobic organisms can’t be too energetic but Anaerobic organisms can’t be too energetic but are important for global recycling of carbonare important for global recycling of carbon

ETCKreb’s Cycle

Releasing chemical Releasing chemical energyenergy

Use your “Releasing Chemical Energy” worksheet to answer questions from the video.

Kreb’s Cycle

Anaerobic Cellular Anaerobic Cellular Respiration: Respiration: FermentationFermentation Some organisms thrive in environments with Some organisms thrive in environments with

little or no oxygenlittle or no oxygen Marshes, bogs, gut of animals, sewage Marshes, bogs, gut of animals, sewage

treatment pondstreatment ponds No oxygen used = ‘an’aerobicNo oxygen used = ‘an’aerobic Results in no more ATPResults in no more ATP, final steps in these , final steps in these

pathways serve ONLY to regenerate NAD+ so it pathways serve ONLY to regenerate NAD+ so it can return to pick up more electrons and can return to pick up more electrons and hydrogens in glycolysis.hydrogens in glycolysis.

Alcoholic FermentationAlcoholic Fermentation Products: Products: ethyl alcoholethyl alcohol, ,

carbon dioxidecarbon dioxide and the and the energy carrier energy carrier NAD+NAD+

Release energy from food Release energy from food molecules by producing 2 molecules by producing 2 ATP molecules.ATP molecules.

Yeast: dough rises due to Yeast: dough rises due to carbon dioxide.carbon dioxide.

Bacteria: present on grapes Bacteria: present on grapes creates the alcohol found in creates the alcohol found in wines.wines.

Lactic Acid FermentationLactic Acid Fermentation Product: Product: lactic acidlactic acid and the energy and the energy

carrier carrier NAD+NAD+

Rapid exercise. Body cannot get Rapid exercise. Body cannot get enough oxygen.enough oxygen.

Run out of oxygen. Produce ATP by Run out of oxygen. Produce ATP by lactic acid fermentation causing lactic acid fermentation causing sore muscles.sore muscles.

Unicellular organisms – lactic acid Unicellular organisms – lactic acid (waste)(waste)

Examples: cheese, yogurt, Examples: cheese, yogurt, buttermilkbuttermilk

Photosynthesis / Cellular Photosynthesis / Cellular Respiration Respiration

Use your “Energy and Chemistry of Life” worksheet to answer questions from the video.