Cellular Respiration, Photosynthesis,

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Cellular Respiration, Photosynthesis, Plants

• I. Cellular Respiration
• Cellular Respiration the process
• that releases energy by breaking
• down glucose other food
• molecules in the presence of oxygen.
• Equation
• 6O2 C6H12O6 6CO2 6H2O
  Energy
• Oxygen glucose carbon dioxide water
  Energy
• (Reactants) (Products)
• The most common source of food energy is found
  in the
• carbohydrates that organisms eat.
• Most important product of respiration is energy
  for life
• processes.

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Cellular Respiration occurs in 3 steps

• 1. Glycolysis process in which 1
• molecule of glucose is broken in half,
  producing 2 molecules of pyruvic acid, a 3-carbon
  compound.
• -End result of glycolysis is 4 ATP
• molecules.
• ATP (adenosine triphosphate)
• main energy-storing molecule
• used by organisms.
• -In the absence of oxygen,
• glycolysis is followed by
• fermentation production of
• ATP without oxygen (anaerobic
• respiration).

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2 Main types of fermentation

• A. Alcoholic fermentation produces alcohol
  CO2 (bread) as wastes.
• B. Lactic acid fermentation produces lactic
  acid that builds
• up in muscle.
• -Happens when the body cant supply
• enough oxygen to the tissues-
• muscles fatigue, ache, or burn.
• -The last 2 steps of cellular respiration
• are aerobic (need oxygen to happen).
• -Oxygens role in cellular respiration
• is to act as the final hydrogen
• (electron) acceptor in the reaction.

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The Krebs Cycle

• 2. The Krebs cycle process by which pyruvic
  acid is broken down into carbon dioxide.
• -The Krebs cycle generates
• high-energy electrons that are
• passed to NADH FADH2.
• -The energy stored in NADH
• FADH2 hydrogen bonds
• are transferred to ATP
• phosphate bonds in the
• electron transport chain.

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Electron Transport Chain

• 3. Electron transport chain
• series of proteins in which
• high-energy electrons are
• used to convert ADP into
• ATP.
• Most ATP produced by
• cellular respiration is
• formed here.

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II. Photosynthesis

• Photosynthesis process by which
• plants use the energy of sunlight to
• convert water carbon dioxide into
• carbohydrates (sugar starches)
• oxygen. Equation
• (Light energy)
• 6CO2 6H2O
  C6H12O6 6O2
• (Reactants)
  (Products)
• (Light energy)
• Carbon dioxide water
  sugar oxygen
• -The most important product of the reaction,
  glucose (an
• organic molecule), is used by plants to store
  energy for the
• production of ATP. No glucose no energy for
  cells.

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Photosynthesis happens in 2 stages

• 1. Light-dependent reactions that
• produce oxygen, ATP, NADPH.
• 2. The Calvin cycle that produces sugars
  (C6H12O6).
• -The separation of carbon from
• carbon dioxide (carbon fixation)
• occurs in the Calvin cycle.
• -The major photosynthetic pigment,
• chlorophyll is needed by plants in
• order to do photosynthesis.
• -Chlorophyll doesnt absorb green
• light, it reflects it. Plants appear to be
• green in color but do not use the green
• wavelength of light for photosynthesis.