Hands-on Activity Sugar Spill!
Bioremediation Cleanup Experiment

Learning Objectives

After this activity, students should be able to:

• Understand the process of bioremediation.
• Explain how engineers make sure bacteria have everything they need to help degrade harmful compounds.
• Gain experience with mass and volume measurements.

Educational Standards

Each TeachEngineering lesson or activity is correlated to one or more K-12 science, technology, engineering or math (STEM) educational standards.

All 100,000+ K-12 STEM standards covered in TeachEngineering are collected, maintained and packaged by the Achievement Standards Network (ASN), a project of D2L (www.achievementstandards.org).

In the ASN, standards are hierarchically structured: first by source; e.g., by state; within source by type; e.g., science or mathematics; within type by subtype, then by grade, etc.

NGSS: Next Generation Science Standards - Science

Common Core State Standards - Math

International Technology and Engineering Educators Association - Technology

State Standards

Materials List

Each group needs:

• 2-4 small test tubes or small plastic water bottles (small enough for a balloon to fit over the opening)
• 2-4 balloons
• 2-4 teaspoons of yeast
• 2-4 teaspoons of sugar
• Graduated cylinder (optional)
• Enough goggles/safety glasses for each group member.
• 3 copies of the Yeast Experiment Worksheet

To share with the entire class:

• Vinegar
• Water
• Hot plate or Bunsen burner
• Other materials students could add to yeast that may hamper or help yeast grow (i.e., lemon juice, chocolate powder, soda, etc.)
• Triple beam balance or digital scale (optional)

Worksheets and Attachments

Pre-Req Knowledge

Students should know how to calculate the volume of a sphere. They should also have some experience with designing their own experiment. If they do not, you may want to add an extra day to this experiment.

Introduction/Motivation

Imagine you are kayaking through the beautiful coastal waters of Alaska. There are bald eagles flying over you, and humpback whales diving in and out of the ocean water near your kayak. Suddenly, you notice an icky black substance dripping off of some of the rocks nearby. What is it? It's the awful sludge of polluting oil, left over from an accidental oil spill in a nearby bay. Luckily, environmental engineers are working hard to help clean up this terrible mess and return the waters to their healthy, beautiful state!

Bioremediation

Bioremediation is the process of using live microorganisms (mostly bacteria) to remediate or clean up pollution, such as manmade chemicals found in oil. Biodegradation is the process of living organisms breaking down matter for energy. What is the difference between bioremediation and biodegradation? Engineering! While biodegradation happens naturally, engineers involved in bioremediation create products that help nature do its job of getting rid of pollutants. Often times, biodegradation does not take place naturally because the bacteria present do not have one of the essential needs of living things (i.e., energy, water, living space and homeostasis). Engineers come to the rescue by providing these needs.

In today's activity, you get to be environmental engineers cleaning up an oil spill through bioremediation. Luckily, there are organisms that can help "eat up" the oil and turn it into harmless substances. Following the important design step of gathering information, you conduct an experiment to see how you can create the right living conditions to make these organisms thrive. In our experiment today, we use sugar to represent the oil, and yeast to represent the organisms that clean up oil by eating it.

When yeast eats, it gives off carbon dioxide (CO2), much like we do when we breathe out. To measure how well the yeast is eating (and therefore cleaning up the spill), we can measure the amount of carbon dioxide it gives off. How do you think we could measure the carbon dioxide gas? (Let students give a few ideas. Give a hint by showing them the balloon.) That's a great idea! Let's put the balloon over the bottle of yeast. As the balloon gets blown up bigger and bigger, we can determine that the yeast is giving of lots of carbon dioxide. Therefore, we also know that the yeast is eating well and cleaning up the sugar spill. The bigger the balloon gets, the better the yeast is eating. By looking at how big the balloon gets, we are able to tell which conditions are most ideal for yeast to grow in.

Procedure

Before the Activity

• Buy and gather supplies.
• Make enough copies of the Yeast Experiment Worksheet so that each student has one worksheet.

With the Students

1. Have students break into groups of 3-4 (you can choose or let the students choose). As a group, students should plan an experiment that helps determine how to make the yeast thrive. Their Yeast Experiment Worksheet guides them through the process.
2. To complete the first page of their worksheet, it may help if you review the scientific method with students. Remind them that a testable question should ask how one variable (the independent variable) affects another (the dependent variable). Give some examples (see Yeast Experiment Worksheet–Answers for suggestions). Also, students may need to be reminded that scientific experiments require that we control our variables. Explain what the control is for this experiment (to make the yeast thrive).
3. Have students plan their experiment. Quickly check their answers on the first page of their worksheet before they begin their experiment.
4. When ready, allow students to start their experiment. The procedure section of the Yeast Experiment Worksheet guides them through the experimental steps. Students should know the exact amount of yeast, water and sugar that went into their control. (Note: it may be useful to have students measure out yeast, water and sugar using the appropriate measuring devices so that they know exact amounts.) Figures 2 and 3 show examples of students measuring yeast and putting a balloon over the test tube.

   

   

5. Results can be recorded on the board so that the entire class can see the results of each experiment.
6. Have students clean up and complete the Post-Activity Assessment.

Vocabulary/Definitions

bioremediation: The process of using microorganisms to clean up an environmental hazard.

microorganism: A life form that is so small, it can only be seen with a microscope.

pollutant: A chemical that causes harm to the environment.

Assessment

Pre-Activity Assessment

Discussion Questions: Solicit, integrate and summarize student responses. Ask the students:

• What is bioremediation?
• What basic things do we need to live?

Activity Embedded Assessment

Yeast Experiment Worksheet: Check student answers during the activity to gauge student mastery.

Post-Activity Assessment

Discussion: Ask students what they found. Which conditions were the best for the yeast? Why? Discuss any uncertainties in data and if there is anything else they should re-test. If they were environmental engineers using yeast for a sugar spill clean-up, what would they add to the yeast so that it would do its job the most effectively?

Safety Issues

Although yeast is used as food, students are in a lab and should not eat it.

Use eye protection (goggles or safety glasses) during this activity.

Troubleshooting Tips

Have students put the balloon half way on the bottle top, add the water and then put the balloon the rest of the way on the bottle top. If students have trouble getting the balloon on, get a smaller container.

If carbon dioxide does not fill balloon, get a smaller balloon or use more yeast.

Reaction times vary, encourage students to come back and check on their balloons if they do not see results within the class period.

It may be useful to seal the balloon to the flask using duct tape or masking tape to prevent air from leaking.

Activity Extensions

If students are interested, or there is funding available, oil eating bacteria kits are available online and may further demonstrate how bioremediation can be applied in the real world. You may start with the following website: https://www.enasco.com/p/SB39284M, but there are several additional sources.

Activity Scaling

For younger students, work through the math calculations as a class using average values.

For older students, have students present their findings to the class along with a suggestion or idea on why bioremediation is important to use in the environment.

References

Copyright

Contributors

Supporting Program

Acknowledgements

The contents of this digital library curriculum were developed under a grant from the Fund for the Improvement of Postsecondary Education (FIPSE), U.S. Department of Education and National Science Foundation GK-12 grant no. 0338326. However, these contents do not necessarily represent the policies of the Department of Education or National Science Foundation, and you should not assume endorsement by the federal government.