Summary
Life trapsAs part of recognizing the characteristics of life that all organisms share, students grow microbes on nutrient agar plates. Students swipe surfaces with a sterile Q tip swab and seed plates resulting in a wide range of colorful and prolific bacteria and fungi colonies. Other plates may be simply opened to the air to catch life floating in the air. Through these experiences, students learn that all living things, even those so small and invisible as to be floating in the air, grow and reproduce when provided with the proper nutrients and water. Teachable moments abound since the “dirtiest places”, like the toilet rim, often result in the least bacterial growth while presumably “clean” places, like the surface of your skin, have the most. A fun extension of this activity (see the Going Further section) is to start a sourdough culture from wild yeast in the air and make sourdough bread.
Objectives
Can grow microbes on nutrient agar plates.
Can make observations and keep track of data over several days.
Can identify the typical growth patterns of bacteria versus fungi.
Can begin to recognize the diversity of microbrial life in the local environment.
Can explain that all living things will grow and reproduce when provided with the proper nutrients and environmental conditions.
Vocabulary
Agar
Nutrients
Microbe
Bacteria
Fungi
Yeast
Colony
