Photosynthesis Experiments

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Photosynthesis Experiments
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This is Photosynthesis
MORE stored energy
Glucose
OUTPUT
INPUT
CHEMICAL ENERGY
LIGHT ENERGY
Carbon dioxide
LESS stored energy
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• We know that plants photosynthesize.
• You will design experiments that provide evidence
  that verifies the INPUTS and OUTPUTS required for
  this process to occur.
• There are 4 possible inputs and outputs for
  photosynthesis. You will pick one and design an
  experiment to test if it is an input or an
  output.

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Our Questions

• Question1--Is carbon dioxide an input or output
  for photosynthesis?
• Question 2Is light an input or output for
  photosynthesis?
• Question 3Is oxygen an input or output of
  photosynthesis?
• Question 4Is glucose (stored as starch) an input
  or output of photosynthesis?
• You will design an experiment to answer one of
  these questions

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• On your handout choose INPUT or OUTPUT for your
  question.
• With your lab group, write a hypothesis for your
  question.
• Then, make drawings of
• the experimental conditions
• the predictions for your hypothesis if it is
  supported and not supported
• Determine the variables (independent, dependent
  and controlled

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Measuring Carbon Dioxide

• Bromothymol blue is an indicator that can be used
  to detect carbon dioxide presence.
• Yellow carbon dioxide present
• Blue NO carbon dioxide

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Measuring Oxygen

• Methylene blue is an indicator for the presence
  of oxygen
• when oxygen PRESENT
• when oxygen LEVELS ARE LOW

BLUE
CLEAR
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Measuring Light !!
If light is the source of energy for the reaction
and is required for the reaction to occur then we
can measure the use or production of either
glucose, CO2 or O2 in the presence or absence of
light to understand lights importance.
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Measuring Glucose (Starch)
Original leaf
Leaf with chlorophyll removed by boiling in
alcohol
Leaf stained with iodine after chlorophyll was
removed (black starch)
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Energy changes-from sun to cells
Glucose
ATP
LIGHT ENERGY
CHEMICAL ENERGY
ENERGY FOR CELLULAR WORK
Carbon dioxide
PHOTOSYNTHESIS
CELLULAR RESPIRATION
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Photosynthesis

• Energy from sunlight is used to build glucose out
  of carbon dioxide and water
• Oxygen is released as an output
• Occurs in chloroplasts using the green pigment
  chlorophyll

• INPUTS
• Carbon dioxide
• Water
• Light

• OUTPUTS
• Glucose
• Oxygen

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Photosynthesis
INPUTS
OUTPUTS
6 CO2
6 H2O
C6H12O6
6 O2
Carbon dioxide
Water
Glucose
Oxygen