Cellular Respiration and Photosynthesis

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Cellular RespirationandPhotosynthesis
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ATP

• Adenosine Triphosphate
• Main energy source for animal cells
• Energy is stored in the bonds between phosphate
  atoms
• Give off LOTS of energy when broken!

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ATP

• ATP is made from ADP
• A new phosphate gets added to ADP to make ATP
• Enzymes catalyze these reactions
• ATPase breaks down ATP
• ATP synthase makes ATP from ADP
• The ATP and ADP molecules get reused over and
  over again BUT energy does NOT get reused.

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Cell Respiration

• Energy stored in glucose is released through a
  process called Cell Respiration. This occurs in
  all living organisms.
• Two types of Cell Respiration
• Aerobic requires O2
• Anaerobic Does not require O2

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Cellular Respiration

• The process of transferring the energy in
  carbohydrates into a useable form of energy for
  the cell (ATP)
• Occurs in the cytoplasm and mitochondria of
  Autotrophs and Heterotrophs
• C6H12O6 O2 ? CO2 H2O ATP Heat

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Cellular Respiration

• Three phases
• Glycolysis
• Anaerobic
• Citric Acid Cycle (Krebs Cycle)
• Aerobic
• Electron Transport Chain
• Aerobic

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Phase I Glycolysis

• Anaerobic does NOT require O2
• Occurs in the cytoplasm
• Series of chemical reactions that break down one
  glucose into two sugar molecules
• Produces 4 ATP molecules
• But it takes 2 to get the reaction started for a
  net production of TWO ATP!

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Phase II Citric Acid Cycle

• Also known as Krebs Cycle
• Aerobic requires O2
• Occurs in the mitochondria
• Glucose is broken down even further
• Products 2 ATP and CO2

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Phase III Electron Transport Chain

• Aerobic requires O2
• Occurs in mitochondria inner membrane
• Electrons from CAC pass thru a chain of proteins
• Products 32 ATP and H2O

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Fermentation

• After glycolysis, if no O2 then fermentation
  occurs
• Fermentation is an ANAEROBIC process!
• Allows cell to continue using glycolysis to
  generate ATP
• 2 kinds of Fermentation
• Lactic Acid Fermentation
• Alcoholic Fermentation

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Fermentation

• Lactic Acid Fermentation
• In animals and some bacteria
• Results in the production of lactic acid
• If too much builds up, can result in muscle
  soreness
• Alcoholic Fermentation
• Yeasts, plants
• Used in bread and alcohol manufacturing

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Fermentation

• Lactic Acid Fermentation
• Bacteria in a closed container of milk are in an
  anaerobic environment so they use fermentation to
  make ATP and the lactic acid produced curdles the
  milk. This is what produces cheese, yogurt, sour
  cream, and cottage cheese.
• Alcoholic Fermentation
• Yeasts in bread dough are also in anaerobic
  environment. CO2 gas is produced as a by product
  and is what makes dough rise. Alcohol evaporates
  out of bread during baking.

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32 ATP
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Energy Summary(number of ATP molecules formed in
each step of respiration)
Glycolysis 2 ATP
Krebs cycle 2 ATP
Electron Transport 32 ATP
Total Aerobic Respiration 36 ATP
Glycolysis 2 ATP
Fermentation 0 ATP
Total Anaerobic Respiration 2 ATP
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Photosynthesis

• Meaning making with light
• Photosynthesis is the process of converting the
  suns light energy into stored carbohydrates
  (glucose)
• Takes place in in the chloroplasts of autotrophs
• The green pigment chlorophyll is required for
  photosynthesis
• CO2 H20 Light ? C6H12O6 O2

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Chemical Reactions

• Two phases
• Light Dependent Reactions
• Turns light energy into ATP
• Light Independent Reactions
• Conversion of CO2 into Glucose

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Light Dependent Reactions

• Light energy transfers to electrons in
  chlorophyll
• Excited electrons pass through a chain of
  proteins
• electrons loose energy at each step, creating ATP
• H20 is split to replace electrons
• Gives off O2

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Light Independent Reactions

• Also known as the Calvin Cycle
• DONT CONFUSE WITH KREBS CYCLE!!!
• Series of reactions that use ATP to convert CO2
  into Glucose
• LOTS of enzymes used
• That Mrs. Ball is nice enough to NOT make you
  know!