BIOL 1202 Lecture : Biology 1202 Unit 1 Notes
Document Summary
Life began on this planet 4 billion years ago: all cells come from pre-existing cells is the cell theory, charles darwin: existing species come from preexisting species. Hypothesis on how life began: a few centuries ago: The theory was discredited due to experiments analysis: spontaneous generation refuted. Mid-1800s louis pasteur: broth in flask is boiled to kill preexisting microorganisms, as broth cools, condensing water collects, sealing the mouth of the flask. If neck is later broken off, outside air can carry microorganisms into broth: conditions on early earth. Ribozymes: rna molecule that can catalyze reactions, especially those involved in synthesis and processing of rna itself: conclusion: earliest cells used rna to store info, ribozymes to catalyze reactions, major classes of amino acids: Hydrophilic: similar to the phospholipid bilayer in the cell membrane, microspheres as proto-cells. Just add fat and protein to water then shakes. Lynn margoulis proposed an explanation where eukaryotic cells came from.
