BIOL108 Lecture Notes - Lecture 2: Cambrian Explosion, Mandible, Carbon-12

• School: University of Alberta
• Department: Biology (Biological Sciences)
• Course: BIOL108
• Professor: Heather Proctor

Document Summary

How was this achieved in protocells: possibly vesicles fluid-filled compartments with a membrane-like structure. Vesicles form spontaneously when lipids are added to water: the rate of vesicle self-assembly was increased by montmorillonite, a soft mineral clay produced by the weathering of volcanic ash. Vesicles can replicate and have a selectively permeable bilayer so they undergo metabolism as well: first genetic material was likely rna. The rate of decay is measured by half-life: fossils contain isotopes of elements for example, a fossil may contain carbon-12 and carbon-14. The amount of carbon-12 in the tissues does not change. By measuring the carbon-14 to carbon-12 ratio, we can date fossils: mammals have unique characteristics, even against other tetrapods, synapsid (300 mil. The articular-quadrate migrated to the ear to form the hammer (malleus) and anvil (incus): fossils helped establish geological record, divided into 3 eons (archaean, proterozoic, Phanerozoic: first two eons lasted ~4 billion years.