Preview - Exploring Homeostasis And Feedback Loops With Diabetes

Does the human body maintain stability in complex systems?

For this investigation, you are testing whether or not the human body maintains stability of two complex systems as external conditions change.  To help you design your experiment, read the purpose and materials list below: 

Purpose:

The purpose of this investigation is to see if two of our internal systems (circulatory and respiratory) maintain stability as external conditions change.  

Materials:

  • 1 test subject
  • Timer
  • Diagnostician to measure breathing rate
  • Diagnostician to measure pulse

NOTE: 

  • Pulse can be taken at the wrist or via the carotid artery (underneath the jawline, by the lymph nodes).  The test subject may take their own pulse. 
  • Breathing rate = 1 inhalation and 1 exhalation as one breath.  The test subject should NOT record their own breathing rate
  • Measurements should be recorded for 30 seconds and multiplied by 2 to determine rate (per minute)

Questions

Please answer the questions below.

How do you plan on changing the external environment of the system (your independent variable)?  

How do you plan on measuring the effect of your change to the system (your dependent variable)?

Don't forget: you should be taking TWO measurements!

Now that you have identified the cause-effect relationship you are testing, make a hypothesis about what you think will happen during the experiment. Remember that your hypothesis should be an if-then statement and should include some form of explanation.  

Here is an example hypothesis: 

If a shell-less egg is placed in distilled water, then the mass of the egg will increase because water moves across the cell membrane by diffusion. 

NOTE: You might not be able to give a full scientific explanation at this point, but you should be able to provide a reason why you think something will happen!

In the space below, provide a summary (or numbered list) of how you will conduct your investigation.  Make sure you are SPECIFIC in terms of units, time, etc. 

Please make sure to explain what type of physical activity your test subject will be performing, specify times, units, modes of data recording, roles, etc. 

Notes

These notes will appear on every page in this lesson so feel free to put anything here you'd like to keep track of.