Energy Transformations: Photosynthesis

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• Energy Transformations Photosynthesis
  Respiration

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Read pages 218-220

• What is energy?
• List 2 processes (in the cell) that require
  energy (the ability to do work).
• What is the difference between an autotroph and a
  chemotroph?
• What is metabolism?

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ATP ADP

• ATP Adenosine triphosphate
• adenine ribose 3 phosphates
• Energy storing molecule, only stores energy for a
  few minutes
• Source of all cell energy
• When one phosphate group breaks off, energy is
  released

Adenine
3 Phosphate groups
Ribose
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• ADP Adenosine diphosphate
• Adenine ribose 2 phosphates
• Molecule that results from ATP losing one P
• Another P may be added later

ADP
ATP
Energy
Energy
Adenosine diphosphate (ADP) Phosphate
Adenosine triphosphate (ATP)
Partially charged battery
Fully charged battery
5
Describe organelles involved in energy
transformation

• Energy transformation is when energy is converted
  from one form to another.
• Energy transformations involve photosynthesis and
  respiration.

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Photosynthesis
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• CHLOROPLASTS
• Found in plant cells, some protists bacteria
  not animal cells
• Contain pigment called chlorophyll (green)
• Allows plants to go through photosynthesis by
  converting light into energy for the cell

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Overview Photosynthesis

• Photosynthesis process using energy from
  sunlight to convert water and CO2 into oxygen and
  carbohydrates (sugar)
• Two parts
• Light dependent reactions produce O2 converts
  ADP to ATP
• Calvin cycle (dark reactions) use ATP from light
  reactions to produce sugars

Light Energy
Chloroplast
CO2 H2O
Sugars O2
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• Chlorophyll green pigment in cells that absorbs
  blue red light energy
• Moves energy to electrons that drive reactions
• Equation for photosynthesis
• 6CO2 6H2O energy ? C6H12O6 6O2

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• MITOCHONDRIA powerhouse of cell
• Releases energy from food molecules
• Found in both animal and plant cells
• A cell that needs more energy has more
  mitochondria
• Ex muscles, growing cells, areas of repair

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Overview cellular respiration

• Respiration process that releases energy by
  breaking down food when oxygen is present
• Equation for Respiration
• C6H12O6 6O2 ? 6CO2 6H2O energy

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• Anaerobic respiration (fermentation) occurs
  without oxygen present
• Two types
• Alcoholic form ethyl alcohol and CO2 as waste
  products used to make bread rise
• Lactic acid produces lactic acid in muscles when
  exercising without enough oxygen

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Photosynthesis Respiration
Function Energy storage Energy release
Location Chloroplasts Mitochondria
Reactants Carbon dioxide water Glucose oxygen
Products Glucose oxygen Carbon dioxide water
Equation 6CO2 6H2O energy ? C6H12O6 6O2 C6H12O6 6O2 ? 6CO2 6H2O energy