In the Spontaneous Generation Demonstration Kit of Pasteur’s experiment for biology and life science, a series of media-filled flasks with different openings and treatments are exposed to air containing microbes.
Prior to Louis Pasteur, there was a commonly held belief that living microbes could arise from nonliving matter by a “mysterious” process known as spontaneous generation. Pasteur was ingenious in designing “controls” into experiments, and his classic S-tube flasks proved to be the key to dispelling the belief in spontaneous generation. You and your students can now easily duplicate Pasteur’s classic experiment with this convenient kit.
In this demonstration, a series of media-filled flasks with different openings and treatments are exposed to air containing microbes. The only flasks that become contaminated are those where microbes can come in direct contact with the media. The S-shape flasks remain sterile even though they are open to the air. Why? Because microbes can’t “navigate” around the S-shaped bend in the glass. Set up in 1864, Pasteur’s open-air, S-shaped flasks are still sterile in a museum in France. Consider keeping the S-shaped flasks in your classroom. They will remain sterile for years to come. Your students will be very impressed! Enough materials are provided for one complete demonstration setup. Includes the pre-shaped S-tube, chemicals and complete teaching instructions.
Concepts: Sterilization, spontaneous generation. Time Required: 25 minutes
Correlation to Next Generation Science Standards (NGSS)
Science & Engineering Practices
Planning and carrying out investigations
Disciplinary Core Ideas
MS-LS1.A: Structure and Function HS-LS1.A: Structure and Function
Crosscutting Concepts
Scale, proportion, and quantity
Performance Expectations
MS-LS1-1. Conduct an investigation to provide evidence that living things are made of cells; either one cell or many different numbers and types of cells