JoVE Lab Manual
Lab Bio
Lab Bio
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Photosynthesis
Learning Objectives
At the end of this lab, students should know...
What is photosynthesis?
Photosynthesis is the conversion of sunlight into usable and storable energy. Autotrophs (such as plants) use carbon dioxide, water, and energy harnessed from sunlight to generate glucose and oxygen through photosynthesis, thus providing a major energy source in the food web.
How do plants harness energy from the sun?
Plants produce pigments, such as chlorophyll that allow them to absorb energy from sunlight. For example, light energy excites the electrons of the pigment molecule. This energy is later harnessed and converted into chemical bonds of simple sugars.
What part of the plant cell is responsible for photosynthesis?
The chloroplast— which contains pigments in its innermost membrane layer known as thylakoids—is primarily responsible for carrying out photosynthesis.
What is carbon sequestration?
During photosynthesis, carbon dioxide is used to generate simple sugars. This carbon dioxide is sequestered or removed from the atmosphere, therefore this process is known as carbon sequestration.
How does photosynthesis influence the climate?
Plants get carbon from CO2, a greenhouse gas and contributor to global warming. During photosynthesis, plants remove CO2 from the atmosphere, which has a cooling effect on the earth.
List of Materials
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Chromatography Strips (18 X 3-4 cm strip)5
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Chromatography Solvent (90% Petroleum ether & 10% acetone, 10 mL)50 mL
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Pipe cleaners5
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Plastic Disposable Syringes (20 mL)10
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Paper clips10
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Petridishes5
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Plastic/glass Beakers (400 mL)15
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Hole punch5
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Ruler5
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Permanent marker5
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Pencil5
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Dawn liquid dish soap (1 Bottle)1 per station
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Spinach leavesDependent on the lab size
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Sodium Bicarbonate/baking sodaDependent on the lab size
Lab Prep
- Plant Pigment Chromatography and Floating Leaf Discs in a Vacuum
- On the day before the experiment, fill a container with water.
- Place the spinach leaves into the water and make sure they are submerged.
- Leave the spinach leaves to soak overnight at room temperature.
- Wearing gloves, prepare and measure out 18 cm x 304 cm sections of chromatography paper.
- Prepare a bicarbonate solution for the second experiment by combining 0.25 g NaHCO3 with 300 mL water. Add one squirt of dish soap to the solution and mix gently.
- If the solution is still sudsy, add more bicarbonate.
- For the control solution, combine 300 mL water with one squirt of dish soap. Mix gently and try to avoid suds.
- Just before the experiment is due to begin, select a few spinach leaves of similar smoothness and thickness without too many large veins.
- Use a hole punch to create 20 uniform discs from the leaves for each student or group.
