Where have we been?

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Where have we been?
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PHOTOSYNTHESIS TYPE II

• WRITE the BALANCED equation for photosynthesis
• LABEL the inputs (reactants) and outputs
  (products)
• EXPLAIN what will happen to each of the products
  and reactants

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Cellular Respiration

• Cells and Energy Release

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MORE FUN WITH TIM MOBY

• http//www.brainpop.com/science/cellularlifeandgen
  etics/cellularrespiration/preview.weml

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Question

• Why do we breathe?
• 4th grade answer so we dont die
• 7th grade answer to take in oxygen, and
  breathe out carbon dioxide
• 10th grade answer TO FUEL CELL RESPIRATION!

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Basic ideas

• Breaking down high energy, large molecules into
  lower energy, smaller molecules.
• If this process stops, cells DIE!!!!
• Requires oxygen to fully occur.
• Three step process
• Step 1 occurs in the cytoplasm of the cell
• Steps 2 3 occur in the mitochondria of the cell

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Heres where it Happens!
"MIGHTY Mitochondria"
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This is the equation!

• C6H12O6 6O2 -gt 6CO2 6H2O energy (ATP
  heat)
• How does this look familiar?
• Where do the ingredients (reactants) come from?
• What happens to each of the leftovers (products)

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WHATS ATP GOT TO DO WITH IT?

• Adenosine Triphosphate
• Chemical energy source for the cell
• Think of it as cellular money

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Three Stages of Cellular Respiration

• STEP 1 Glycolysis (GLUCOSE SPLITTING)
• 1st stage of ALL energy releasing pathways.
• Occurs in cytoplasm
• A couple of ATP coins made
• If youre fermenting, stop here!
• STEP 2 Krebs Cycle (citric acid cycle)
• Occurs in the mitochondria
• A few more ATP coins made
• STEP 3 Electron Transport Chain
  (phosphorylation)
• Occurs in the mitochondria (membranes)
• ATP JACKPOT!!!!!!!!!!!!!!

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CELL RESPIRATION OVERVIEW

• Convert glucose to ATP
• Accomplished in 3 steps
• Glycolysis?in cytoplasm
• Krebs Cycle?in mitochondria
• Electron Transport Chain?in mitochondria
• Remember this requires Oxygen

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• Glycolysis
• Food must have been transported to cells via the
  bloodstream
• digested food gets into the bloodstream by
  diffusing through the intestinal walls into the
  capillaries.
• 1st stage in energy release from food
• Input glucose,
• Outputs small amount of ATP and pyruvates
• These outputs are the inputs for the next stage

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• Krebs Cycle
• Series of chemical reactions
• ATP (energy) released
• CO2 (waste) released

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• Electron Transport Chain
• Series of reactions
• Releases LOTS more ATP

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CASHING IN

• Total energy released from 1 GLUCOSE MOLECULE
  DURING CELL RESPIRATION

38 ATP
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CELL RESPIRATION OVERVIEW

• Convert glucose to ATP
• Accomplished in 3 steps
• Glycolysis?in cytoplasm
• Krebs Cycle?in mitochondria
• Electron Transport Chain?in mitochondria
• Remember this requires Oxygen

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UH, OHPROBLEM

• 1.) What if you dont have mitochondria?
• 2.) What if there isnt much oxygen around?

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FERMENTATION TO THE RESCUE!

• 2 KINDS
• Alcoholic
• Lactic Acid
• These are ANAEROBIC processes
• Little to no oxygen required

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BIG PICTURE When are these used?

• CELL RESPIRATION
• Eukaryotes with mitochondria
• Adequate oxygen
• Ex.
• Animals
• Plants
• PRODUCES LOTS OF ATP!

• FERMENTATION
• Prokaryotes (no mitochondria) AND/OR
• Inadequate or no oxygen available
• Ex.
• Yeast
• Bacteria
• Overworked Human muscles (no, your brain is not a
  muscle!)
• Produces very little ATP, but hey, some is better
  than none!

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Where ARE we GOING?