Summer Research Program For Science Teachers


Zulema Jones-Enoe

Juan Morel Campos Secondary School

Brooklyn, NY


August 2004



Why is Excretion Necessary for Life?




Topic: Excretion as a life function


Standards:      S4a: demonstrates an understanding of big ideas and unifying concepts

S5b: uses concepts from science standards 1 to 4 to explain a variety of observations and phenomena

                        S5f: works individually and in teams to collect and share information


Learning Objectives

At the end of the lesson students should






Do Now

Students will be given 5 minutes to answer

  1. What would happen if someone never threw out his or her garbage and leftover food?
  2. How can sweating be seen as a good thing?  When do you think it is most important to sweat?



All organisms need to perform the life processes to prevent extinction, or dying out. Humans and most complex animals perform these life functions in order to maintain homeostasis. One of the life processes is excretion.  Excretion is the removal of waste products by an organism.  Some waste products are sweat, urine, and carbon dioxide. Without the excretory system many problems can develop in the body.



Have students work in groups of 2-3 (based on class size) and go to Trackstar website (TRACK #98785), an listing of five websites on the excretion system.  Each group should share one computer. This site was created byKim Swan.

Have students take 15-20 minutes to look at the websites and answer the questions on each website page in the assignment section.  Each student is to hand in a paper with the answers to the questions and their student work sheet.  To assist with time-you may have each group just look at one website and report their answers to the class.

Discuss class responses.



The excretory system is important for many reasons.  Similarly to your need to take out the garbage, to prevent nasty smells, clutter and invasions by other organisms the excretory is like taking out our garbage.  Problems can develop from malfunctions of the excretory system.  Some things we can do are: eating healthy foods, drinking lots of water and proper hygiene. 



What other life functions are closely related to the excretory system?

Have students research any diseases of the excretory system (the causes, the effects and how it is treated).



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Student Worksheet


Excretory System




Body Part


Waste Product Removed

Possible Problems (if known)