Learning Aims:

    Students are expected to

    • develop a testable hypothesis
    • design an experiment (whether virtually or a real) that will answer a question about photosynthesis
    • present collected data in the form of tables and graphs
    • explain results using scientific knowledge
    • use data and observations to form a conclusion.
      • digital data logger
      • ice cubes
      • CO2 gas sensor
      • 1 L beaker
      • O2 gas sensor
      • thermometer
      • 250 mL respiration chamber
      • plant material
      • lamp with adjustable light intensity
      • coloured films
      Suggestions for use:
      This part of learning is provided with alternative strategies and suggestions that the teacher can choose, depending on existing resources. Alternatives are given as activity 3a, 3b, 3c.
      Students will be given the materials and asked to design an experiment to answer the question. When they have finished planning their experiment the students will be required to set up their experiment and record their hypothesis and rationale of what will happen in their experiment. Students will make observations and collect data from their experiment. They will record their results in a data table.The students will form conclusions based on their data and explain any anomalies. The results of students’ inquiry will hopefully feed the ideas of students’ space project.
      Activity 5a Using computer models to explore the factors controlling photosynthesis (effects of light intensity and wavelength on the rate of photosynthesis)
      In this simulation, students will stimulate two variables: light intensity and light wavelength. The amount of ATP produced will change depending upon the set parameters. The simulation "Johnson Explorations: Photosynthesis“ is located at http://www.mhhe.com/biosci/genbio/biolink/j_explorations/ch09expl.htm
      The students’ task is to use the simulation to determine how wavelength and intensity affect the rate of photosynthesis (and the production of ATP).
      In addition, valuable animations of the processes can be found at the website: http://science.nhmccd.edu/biol/bio1int.htm#photo
      Technology in the classroom, when available, provides an ideal situation in which multiple representations of information can be disseminated to the students.
      Activity 5b. Using digital sensors and data logger to explore the factors controlling photosynthesis (effects of light intensity and wavelength, temperature and on the rate of photosynthesis)
      In this experiment, students will
      • Plan and carry out an experiment on factors controlling photosynthesis
      • Study the effect of at least one condition (light intensity, wavelength, plant, or temperature) on the rate of photosynthesis
      • Use an O2 Gas Sensor to measure concentrations of oxygen gas.
      • Use a CO2 Gas Sensor to measure concentrations of carbon dioxide gas

      Activity 5c. Using pond weed to explore the factors controlling photosynthesis

      (Source: http://9arevision.wikispaces.com/plants)

      This alternative is given in case the other possibilities are unavailable. It takes more time to get visible results (oxygen displacing water), still, all the aforementioned variables are testable.

      Possible questions:
        • How do different factors influence the intensity of photosynthesis?