BSC 196 Lecture Notes - Lecture 8: J. B. S. Haldane, Water Vapor, Alexander Oparin
Document Summary
Conditions on early earth made the origin of life possible. Chemical and physical processes on early earth may have produced simple cells through four stages: Synthesis of macromolecules (bigger and more complex) In the 1920"s, ai oparin and jbs haldane hypothesized that the early atmosphere was a reducing (electron adding) environment. Water vapor plus compounds from volcanic eruptions. Organic molecules could have formed from simple molecules. In 1953, miller and urey conducted lab experiments showing that synthesis of organic molecules in a reducing atmosphere is possible. Apparatus used: vapor from boiling water circulated through an atmosphere of methane, ammonia, and hydrogen. Small organic molecules alone not sufficient for life. Rna nucleotides have been produced spontaneously from simple molecules. Small organic molecules form on hot substrates. Life must reproduce and have a metabolism. Cells need enzymes to carry out cellular functions (normally proteins) Seems unlikely dna and proteins appeared at the same time.
