Body Balance Biology

Secondary ProgramsOnsite

Our body is constantly maintaining balance between our internal and external environments.

Research has indicated that elite endurance athletes have problems regulating their internal body temperatures. It has been shown that the cause of this fault is a poor functioning thyroid gland resulting in lower amounts of thyroxine.

In this program students will perform tests to diagnose an elite athlete with hypothyroidism. They will first establish a normal functioning negative feedback loop for temperature regulation and then determine what factor does not work in the effected athlete. Students will then debate if the treatment for the condition is performance enhancing.

Learning Intention:

To understand how scientists test for the presence of a hormone and determine its role within a negative feedback system.

Success Criteria: 

  • Explain the role of a negative feedback system in maintaining a stable internal environment.
  • Identify the role of antibodies when testing for a hormone.
  • Interpret the colour change results of an ELISA test, in regards to solute concentration.
  • Use graphical representations of the body’s internal responses to identify a malfunction in a feedback loop.
  • Relate the role of thyroxine to an athlete’s performance.

Students will:

  • Complete an ELISA test for thyroxine.
  • Interpret results from ELISA.
  • Interpret a series of graphs.
  • Construct a negative feedback loop for temperature control based on ELISA results.
  • Make judgements on the effects of thyroxine.


Program suitability

VCE VCE Biology Unit 1-2

Program duration

2 Hours

Class size

12 - 28
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