Name: ______________________________


How Does Temperature Affect Respiration Rates of Fish?

Introduction:  In this lab you will slowly change the water temperature of a fish and determine how changing the temperature affects the fish's respiration rate

Prediction:  How do you think the temperature affects breath rate?
  As the temperature increases, the respiration rate will:  

increase, decrease, or stay the same.  (circle)


1.  The goldfish will start at room temperature.  Check the temperature and record the number of breaths the fish takes at room temperature for 30 seconds.
2.  Use an empty bowl and add cold, icy water.  Place the fish beaker in the ice bath. 
3.  Place a thermometer in the fish's beaker and watch as the temperature slowly changes.  When it reaches each of the ranges in the data table, determine how many breaths the fish takes.
4.  Replace ice bath with warm water bath to raise temperature.


Temperature Range

Actual Temp (read thermometer)

Your fish

Fish 2

Fish 3

Fish 4

Fish 5


26-29 C








23-25 C








18-22 C (room)








15 - 17 C








11 - 14 C








10 or below










1.  Describe how the fish's respiration rate changes with the temperature.



2.  Propose an explanation for why the respiration changed in this way.



3.  What other factors (besides temperature) may have affected the rate?


4.  Was the “average” similar to your fish data?  Why do we take an average?


5.  Was your prediction at the beginning of the lab correct or incorrect?


6.  Design an experiment that will test how a fish's respiration rate is affected by light.  Explain your design.  You may wish to draw a picture of your set-up.   Include how you will change the environment and what you will be measuring.





7.  Supposing this experiment was repeated using an endothermic (warm-blooded) animal as a test subject instead of a fish.   Heart and breathing rate is monitored for a mouse as the temperature is raised and then lowered.   Will the mouse’s breathing and heart rate change?  Why or why not?

graph 2


8.  Indicate on the graph which line would represent the endothermic animal and which line would represent the ectothermic animal.   Explain how you know this.