ScienceSource.ca Dry Lab Activity

Unit A - Chapter 1

Investigating Science 9

Inquiry Activity

Eye on Photosynthesis

Skills Reference 2

Skills you Will Use

  • Using appropriate equipment and tools
  • Drawing conclusions

Safety

  • Glassware
  • Goggles

Caution

You will use beakers and test tubes in this activity. Take care when handling glassware.

Wear goggles to protect your eyes from the materials used in this lab.

The process that plants use to capture the energy in sunlight may be complex, but it is actually fairly simple to study. One of the products of photosynthesis is oxygen gas, so if photosynthesis takes place underwater, oxygen gas should form bubbles.

In this lab, the aquatic plant Elodea canadensis will be used to determine specific conditions that are required for photosynthesis.


Question

What raw materials and conditions are involved in photosynthesis?


Materials and Equipment

  • elodea plants
  • wide mouth large beaker
  • sodium bicarbonate (baking soda) solution
  • 2 test tubes
  • wax pencil
  • lamp (optional)

Dry Lab

A "dry lab" activity includes collected data and/or a video solution for your convenience. You can simply watch the following video and use the provided data, or if you wish to perform this lab for yourself, follow the procedure steps 1 through 9 described in the video. The same steps are included in written form in the documents available for download on the bottom of this page.



Forming Conclusions

  1. A student performing the procedure steps 1 through 9 collected the following results.

    Solution

    Test Tube Contents

    Observations

    Sodium bicarbonate

    None

    No bubbles

    Sodium bicarbonate

    Elodea

    Bubbles, collecting into a pocket of oxygen above the water over 30 minutes

    Boiled and cooled water

    None

    No bubbles

    Boiled and cooled water

    Elodea

    No bubbles

    Based on these results, what is your conclusion regarding the requirements for photosynthesis?

  2. A student designs an experiment similar to procedure steps 1 through 9, but sets up the whole apparatus twice, and places one beaker in bright light and the other beaker in dim light. What would you expect for the results of this experiment?
  3. Is oxygen the only product of photosynthesis? Explain.