Cellular Respiration Conversion of Chemical Energy in organic compounds (foods) to chemical energy of ATP, usable by cells.
9-3 : RespirationHow does glycolysis produce ATP? How is ATP produced in aerobic respiration? Why is fermentation important?
Cellular respiration is the process used by humans and other organisms to release the energy stored in the food they consume
Cellular respiration ALL cells break down complex organic (prokaryotic and eukaryotic) (foods) compounds into simpler molecules. Cells (catabolism) use some of the energy that is released in(from C-C) this process to make ATP. (happens in respiration and fermentation)
Aerobic Cellular RespirationAerobic requires oxygenAnaerobic does not need oxygenCellular respiration occurs in the cell, in eukaryotic cells it is in the mitochondria. It does not refer to breathing although it requires oxygen.
Parts of RespirationGlycolysisIn cytoplasm, no oxygen necessary, ALL cellsSplits a glucose moleculeGenerates 2 ATP and 2 pyruvates ( pyruvic acids )
In matrix of mitochondria, needs mitochondriadoes not require oxygenSplits C-C bonds ( in acetyl )Generates some ATP, lots of NADH and FADH2 and CO2 as waste
Electron transport chain (ETC)
On the inner mitochondrial membraneElectron transport moves e- from carrier to carrier in the membraneGenerates ATPRequires oxygen as the final e- acceptorAlso makes water
fermentationIf oxygen is missing ETC can not proceed. This causes a build up in NADH. In order to recycle NADH to NAD+ and run the Krebs cycle, cells will use an alternative pathway called fermentation.Must have correct enzymes. FormsLactic acid fermentation ( muscles lactic acid)Alcoholic fermentation (yeast and bacteria alcohol)
EnergyAll cells need/ use ATPATP is adenosine tri phosphate and stores energy in high energy phosphate bonds1 kilocalorie = 1000 caloriesGlycolysis alone is only 3.5% efficientComplete oxidation is 66% efficientCar engines are around 25% efficientCell work generates lots of heat
S u m m a r y
C6H12O6 + 6O2 6CO2 + 6H20 + energyC(H2O)n
food is burned producing exhaust and energy needs oxygen ATP & heat
Compare and contrastRespirationAll eukaryoticAll cells do glycolysisCarbs and oxygen INWater and CO2 OUTMitochondriaInner membrane and matrix3 partsETC is final step; makes ATPReleases energy from C-CCycle; Krebs, separates CATP, NADH and FADH2PhotosynthesisOnly plant cells? Algae and ? bacteriaCarbs and oxygen OUTWater and CO2 INChloroplastThylakoid membrane and stroma2 partsLight reaction has ETC and makes ATPStores light energy as C-CCycle; Calvin, connects CNADPH