Homeostasis Lab: The Effects of Exercise on Homeostasis

 

A: Purpose:  To discover the effect that various levels of exercise have on specific body parameters.

 

B: Hypothesis: How do you predict the 5 observed and measured parameters will change as the subject exercises?

 

C: Materials: Thermometer, stopwatch (you can use your cell phone), rubbing alcohol, cotton balls.

 

D: Introduction

Exercise causes many homeostatic factors to kick in, in an effort to maintain internal homeostasis.  How exercise affects some of these homeostatic factors can be determined by measuring and observing certain parameters such as:

-          change in skin color on arms and face

-          perspiration level

-          external body temperature

-          heart rate

-          breathing rate

In the following lab, 1 member of your group of 4 will exercise for 12 minutes by running in place.  The parameters listed above will be recorded at rest, 3 minutes, 6 minutes, 9 minutes and 12 minutes, and 1 minute after exercise has stopped.  The subject should stop just long enough for the needed measurements to be taken.  Record all data in the table provided. 

 

E: Procedure

1.  Each group should obtain: a thermometer and a stopwatch (or use your cell phone).  Clean your thermometer with alcohol.

2.  Record the resting observations and values of your subject for each of the 5 parameters.  Have one person be the recorder, another person do a-b, another person do c, while the runner counts for d-e.

  1. Record normal skin color of hands and face (i.e. pale, pink, red, etc.)
  2. Record normal perspiration level (i.e. none, mild, medium, high, etc.)
  3. Record external body temperature by placing the thermometer under the subjects arm pit for one minute (note: measurements should be taken directly from the skin).
  4. Determine the heart rate by counting the number of heartbeats taken in one minute.
  5. Determine the breathing rate by counting the number of breaths taken in one minute.

3.  Have your subject begin to run in place.  Please note your subject should be sure to exercise at a level they can maintain for the entire 8 minutes.

4.  Take your subject's parameter readings using the same techniques described above at the 3, 6, 9, and 12 minute time markers.  Be sure to take final readings 1 minute after your subject has stopped exercising.

5.  Record all of your parameter readings in the table provided.

6.  After cleaning your thermometer with ethanol, return it along with the other lab materials in your box to the front of the room.

7.  Answer all post lab questions.

 

F: Observations 

 

 

Body Color

Perspiration Level

Body Temp (Celsius)

Heart Rate (beats/min)

Breathing Rate

(breaths/min)

 

REST

 

 

 

 

 

 

 

 

3 min of exercise

 

 

 

 

 

 

 

6 min of exercise

 

 

 

 

 

 

 

9 min of exercise

 

 

 

 

 

 

 

12 min of exercise

 

 

 

 

 

 

 

1 min after exercise

 

 

 

 

 

 

 

G: Analysis

1.  Plot your measured data on 3 graphs.  You should plot 1 graph each for body temperature, heart rate, and breathing rate versus the duration of exercise (i.e. rest, 3, 6, 9, 12, 13 min). 

2.  Describe your results for each of the 5 parameters.

 

H: Post lab Questions

1.  What are the changes you observed in body color and perspiration level in response to?  How do these changes contribute to the maintenance of homeostasis?

2.  Why do you think a change in body temperature occurs?  What mechanisms does your body use to maintain its homeostatic temperature?

3.  Why does an increase in heart rate and breathing rate accompany exercise?

4.  By studying your parameter measurements after exercise has stopped, what conclusions can you make about your body’s ability to maintain homeostasis?