Middle School Inquiry Lab on the Excretory System
In this lab, students will build a model to simulate the kidneys functioning at varying levels. Students will be asked to explain the role of the kidneys by comparing the function of healthy and unhealthy kidneys and relating this process to the overall function of the excretory system.
Each inquiry lab will contain an essential question that will drive the lesson and make students think. For this lesson, the essential question is:
- What is the role of the kidneys?
BACKGROUND INFORMATION AND MATERIALS LIST:
Students will begin the lab by reading the essential question and background information. This can be done individually, as lab groups, or as a whole class. If you consider lab groups, you also might include some type of whole class formative checks before digging into the lab.
Materials List:
- 3 100 mL beakers
- 3 funnels
- 9 filters (coffee filters of filter paper cut into a circle)
- 50 mL graduated cylinder
- red food coloring
- 27 cotton balls
- 250 mL beaker holding 200 mL of water
- stopwatch
PROCEDURE:
Students will have to collect materials from the teacher that will help simulate the function of kidneys. As the students follow the instructions, they will make observations as to what the outcomes are. Once the students have completed the lab, they will then have to analyze the results of the tests and diagnose each beaker with a urinary condition provided with the lab.
CHECK FOR UNDERSTANDING:
At this point in the lab, students will be checked for understanding by answering questions about their findings. Here are a few that come with the lab:
- What was the color of the cotton balls in each beaker when the trial was over?
- In which beaker did the red color get rinsed out of the cotton balls the least?
- If the food coloring represents wastes that need to be removed, which beaker had the healthiest kidneys?
- Match up the rate of flow with the information about kidney function in the table of the first page of the lab. What level of kidney function is represented by Beaker A, Beaker B, and Beaker C in the lab? Explain.
- Predict the symptoms that each of the three “patients” (Beakers A, B, and C) would be experiencing based on their predicted kidney function.
CONCLUSION
Students will go back to the essential question and write a CER (Claim, Evidence, Reasoning) to conclude the lab. Once completed, students will reflect back on their learning by answering the following questions:
- How does the filtered water differ in each beaker? Pay attention to the color.
- How does this model represent the function of the kidneys?
MODIFIED AND INDEPENDENT INQUIRY VERSIONS
All of the Kesler Science inquiry labs come with three different modification levels. Each lab is differentiated using the icons below.
STANDARDS ALIGNMENT
TEKS: 7.12B – Identify the main functions of the systems of the human organism, including the circulatory, respiratory, skeletal, muscular, digestive, excretory, reproductive, integumentary, nervous, and endocrine systems.
