BIOL 1202 Study Guide - Midterm Guide: Louis Pasteur, Spontaneous Generation, Folic Acid
Document Summary
How did life begin: a few centuries ago, people thought that new living things appeared all of the time. (maggots in garbage, mold on bread, etc. ) 1609- spontaneous creation of life: ***spontaneous generation was refuted by louis pasteur in the mid 1800s; boiling the broth in the flask would kill the preexisting microorganisms. As the broth cooled, the condensing water collected, sealing the mouth of the flask. Pasteur broke the neck off of the flask and the outside air carried microorganisms into broth: conditions on early earth: Atmosphere: co2, ch4, nh3, h2, n2, hcl, h2s, and h2o; similar to jupiter today. No ozone layer: earth before life arose. Earth is about 4. 6 billion years old: radiometric dating of meteorites and moon rocks. Rate of decay of 40k to 40ar: potassium 40 (40k) naturally decays to argon 40 (40ar) (half life of 1. 3 billion years)
