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C4.2.16—Secondary production as accumulation of carbon compounds in biomass by heterotrophs


Here are experiments our science specialists have selected to support this IB* topic.

Biochemical Oxygen Demand

Experiment #16 from Investigating Environmental Science through Inquiry

In the Preliminary Activity, you will gain experience using a Dissolved Oxygen Probe as you determine the DO level of a water sample provided by your teacher.

After completing the Preliminary Activity, you will first use reference sources to find out more about BOD before you choose and investigate a researchable question dealing with BOD.

Interdependence of Plants and Animals

Experiment #14 from Biology with Vernier

In this experiment, you will

  • Use a Dissolved Oxygen Probe to measure the dissolved oxygen in water.
  • Use a pH Sensor to measure the pH of water.
  • Use pH measurements to make inferences about the amount of CO2 dissolved in water.
  • Determine whether snails consume or produce oxygen and CO2 in water.
  • Determine whether plants consume or produce oxygen and CO2 in the light.
  • Determine whether plants consume or produce oxygen and CO2 in the dark.

Educational Standard
International Baccalaureate (IB) 2025
C Interactions and interdependence
Level of organization
4 Ecosystems
C4.2 Transfers of energy and matter
Standard level and higher level

* The IB Diploma Program is an official program of the International Baccalaureate Organization (IBO) which authorizes schools to offer it. The material available here has been developed independently of the IBO and is not endorsed by it.