Microbes Rule!

Activities

Microbe Sort

Students will be given pictures of microbes to sort and classify in small groups. The students develop questions about the microbes as they sort the images. The sort will introduce the students to the different shapes and modes of locomotion used by microbes and lead to a rich, student-led discussion.

Biodiversity

In small groups, students conduct a census of visible species in the soil. In order to perform this activity, the students dig a 12-inch square in the school garden. As they dig, they place the soil they remove on a tarp. The students then comb through the soil, picking up any living organism that is safe to handle with their bare hand that they see with their naked eye. Plastic cups and sand toys can also be used for picking up the organisms. Posters will be attained to help the students to identify the species found. The class will compile the information, determine if the ecosystem has a variety of species (biodiversity), and make predictions about the population of species that are invisible. For example, if the students find a number of springtails and understand that they eat bacteria and fungi, they can predict that bacteria and/or fungi are in the soil. A few student photographers will capture the images. Students will determine the number of organisms and the diversity of the species found. Students will then graph their data.

The students will repeat this procedure in a different part of the schoolyard. Prior to conducting the data collection, students will analyze the soil and make predictions about the amount of organisms they will find. The results of a different location will be compared using a Venn diagram, and conclusions will be drawn about the health of the soil.

Berlese Funnel

The students, working in small groups will make a Berlese funnel, which is an inexpensive way to extract smaller organisms from the soil. In the teacher resource section, the Youtube video that shows how to make the funnel is listed. The students will construct their funnel using a 2-liter soda bottle, a piece of mesh, and a small cup of isopropyl alcohol. Then a soil sample from the garden will be placed in the funnel and the light source will shine on the soil sample. The students will filter out the organisms, gather their data, and once again, construct a graph to display the data. Students will make predictions about the smaller organisms that are in the soil, based on the organisms that they find with their Berlese funnels.

Protozoa Extraction

The final activity will allow the students to see the protozoa that live inside of termite guts. Using several termites that are found in some rotting wood, or purchased from Carolina Biological, students will extract the protozoa from inside the termite by gently squeezing its body. Using a pipette and mild saltwater, students will prepare a slide. Then students will use a microscope to look at the protozoa. If time permits, the students will draw the protozoa seen through the microscope.