Featured in PASCO’s Biology through Inquiry Teacher Guide

Biology through Inquiry Teacher Guide


Features 25 inquiry based labs covering the fundamental concepts of cell biology, ecology and physiology.

Plant Photosynthesis

Lab Summary

Use a carbon dioxide gas sensor to understand the comparative concentrations of CO2 gas for a small plant in darkness and in bright light and what this says about photosynthesis and the CO2 cycle.


Guide students to understand the roles of cellular respiration and photosynthesis in the carbon cycle.

  • Explore the concentrations of carbon dioxide (CO2) gas in a terrarium containing a live plant, in darkness and bright light conditions.
  • Use evidence from measured CO2 gas concentrations to draw conclusions about the processes of cellular respiration and photosynthesis.



  • Sample Student Handout (399 KB – PDF)
  • Sample Teacher Information (451 KB – PDF)
  • Method

    • Students use a carbon dioxide gas sensor to monitor the CO2 levels in a terrarium containing a small plant under conditions of darkness and in bright light.
    • Students use graph analysis tools to compare changes in CO2 levels in the terrarium after 10 minutes under two light conditions: bright light versus darkness.

    Sensors / Equipment Used:

    PASPORT Carbon Dioxide Gas Sensor


    The PASPORT Carbon Dioxide Gas Sensor measures carbon dioxide concentration CO2 (parts per million) in gases such as air. Ideal for studies of photosynthesis, respiration, fermentation and more.

    Materials Used:

    Sampling bottle (included with PS-2110)

    Sensor extension cable (included with PS-2110)

    Large beaker or aquarium (to keep the light source from heating the sample)

    Box or heavy cloth (to cover the bottle)

    Aluminum foil, 1 ft

    Lamp, 100-W (or equivalent)

    Mint, or similar, plant


    Your Bundle Options:

    Option 1:

    Biology Starter Sensor Bundle


    A sensor bundle specifically designed to get you started using probeware in your biology lab. Also: perform 10 of the 24 Lab Activities from Biology with Inquiry.

    Option 2:

    Biology Standard Sensor Bundle


    The Biology Standard Sensor Bundle includes a photosynthesis tank and the sensors required to perform 19 of the 24 Lab Activities in the Biology through Inquiry manual.

    Interface Required

    This experiment may require software and an interface for data collection.