Exercise 7: Respiration

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Exercise 7Respiration
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Two Modes of Energy Acquisition

• Autotrophs Self-nourishing
• Photoautotrophs Carbon source is CO2 from the
  air and sunlight is the energy source that drives
  synthesis.
• Heterotrophs Feed on autotrophs.

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The question that will be addressed

• How do cells release this acquired energy?

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Two Main Types of Energy Releasing Pathways

• Aerobic Respiration Requires oxygen
• Starts in the cytoplasm
• Completed in mitochondrion
• Anaerobic Respiration Does not require oxygen.
• Starts in the cytoplasm
• Completed in the cytoplasm

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Two Pathways
start (glycolysis) in cytoplasm
start (glycolysis) in cytoplasm
completed in mitochondrion
completed in cytoplasm
Aerobic Respiration
Anaerobic Respiration
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Overview of Aerobic Respiration
CarbonDioxide
Water
Glucose
Oxygen
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Aerobic Respiration Occurs in Three Stages

• 1. Glycolysis the breakdown of Glucose to 2
  molecules of Pyruvate
• Occurs in the Cytoplasm
• Results in the net production of 2 molecules of
  ATP and 2 molecules of NADH
• 2. The Krebs Cycle the breakdown of Pyruvate
  to CO2 and H2O
• Occurs in the Mitochondrion
• Results in the net production of 2 molecules of
  ATP, 8 NADH and 2 FADH2
• 3. Electron Transfer Phosphorylation generates
  ATP and H2O
• Occurs in the Mitochondrion
• Results in the net production of 32 molecules of
  ATP

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Anaerobic Respiration I
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Anaerobic Respiration II
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The Circle of Life
sunlight energy
PHOTOSYNTHESIS
water carbondioxide
sugarmolecules
oxygen
AEROBICRESPIRATION