Photosynthesis Experiments

• What is tested to show the presence of starch?

  A leaf
• What are the essential components for photosynthesis?

  Light, chlorophyll, and carbon dioxide
• What does a plant convert glucose into if not used immediately?

  Starch
• What is the first step in testing a leaf for starch?

  Place it in boiling water
• Why do you place the leaf in boiling water?

  To kill the leaf
• What should you use to remove chlorophyll from the leaf?

  Boiling ethanol
• What safety measure should be taken when heating ethanol?

  Use a water bath
• What is done after removing chlorophyll from the leaf?

  Wash the leaf with water
• What happens when iodine solution is added to the leaf if starch is present?

  It turns from yellow-brown to blue-black
• What type of leaves are used to prove chlorophyll is needed for photosynthesis?

  Variegated leaves
• What does a variegated leaf look like?

  Green in some areas, white in others
• What should you do with a destarched variegated plant to test for chlorophyll?

  Place it in sunlight for several hours
• What do you do after placing the destarched variegated plant in sunlight?

  Test one of its leaves for starch
• What is the process to test for starch in a leaf?

  1. Boil the leaf in water to kill it.
  2. Place the leaf in boiling ethanol to remove chlorophyll.
  3. Wash the leaf with water.
  4. Spread the leaf on a white tile.
  5. Add iodine solution; observe color change.
• What is the significance of variegated leaves in testing for chlorophyll's role in photosynthesis?

  • Variegated leaves have green and white areas.
  • Only green areas contain chlorophyll.
  • Testing reveals if chlorophyll is necessary for starch production.
• What is needed for photosynthesis?

  Light
• How can you prove light is needed for photosynthesis?

  Cover part of a leaf and test for starch
• What should you do after covering part of the leaf with black card?

  Place the plant in sunlight for several hours
• What is the purpose of testing the leaf for starch after sunlight exposure?

  To check if photosynthesis occurred
• What chemical is used to prove carbon dioxide is needed for photosynthesis?

  Soda lime
• How do you set up the experiment to prove carbon dioxide is needed for photosynthesis?

  Seal a destarched plant in a bag with soda lime
• What should you do after sealing the bag with the plant and soda lime?

  Place the plant in sunlight for several hours
• Why is it important to test the leaf for starch after the carbon dioxide experiment?

  To confirm if photosynthesis took place
• What aquatic plant is used to prove oxygen is given off during photosynthesis?

  Elodea
• How can you prove oxygen is produced during photosynthesis?

  Collect gas in an upturned test tube above a plant
• What should you do with the gas collected in the test tube?

  Place a glowing splint inside the tube
• What does it indicate if the glowing splint relights in the test tube?

  Oxygen is present in the gas
• Fill in blanks for experiment.

  A) starch

  B) starch

  
• Fill in the blank for what kind of experiment it is.

  A) prove carbon dioxide

  
• What type of plant is commonly used in this experiment?

  Elodea