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In biology classes, students are typically taught that spontaneous generation does not take place. And yet, at the origin of life, life had to arise without parents from abiotic processes. What were those processes that gave rise to the first life?  This case study uses an interrupted format to guide students through the Miller-Urey experiment of 1953, which showed that organic molecules could be produced from abiotic precursors and conditions thought to be prevalent on the early Earth. The case also addresses the more speculative implications about where these reactions may have taken place to create the organic building blocks of life on this planet. The first three parts of the case, which explore the Miller-Urey experiment, are ideal for introductory biology courses and take about 45-50 minutes to complete. The remaining sections, which explore whether such chemical reactions took place in outer space, were used in a non-major astrobiology course and require a further hour to complete.

Hank tells us the stories of three experiments in biology that, with creativity and luck, changed science & the world with it in their work to solve the mysteries of the universe.

Germ theory states that specific microscopic organisms are the cause of specific diseases. The theory was developed, proved, and popularized in Europe and North America between about 1850 and 1920. Because its implications were so different from the centuries-old humoral theory, germ theory revolutionized the theory and practice of medicine and the understanding of disease. It was, however, compatible with existing ideas about health, especially those associated with 19th-century hygiene and sanitation.