BIO153H5 Study Guide - Final Guide: Nuclear Membrane, Cell Membrane, The Empire Strikes Back
Document Summary
*do not cover archea or bacteria in lectures, but sections . 1-. 3 is testable. Protists form main basis of aquatic food chains. Nuclear envelope originated from the folds of the plasma membrane: ancestors existed with chromosomes, plasma membrane began to fold in, formation of nuclear envelope occurred. Nucleus allowed for innovation in gene expression: archaea and bacteria: transcription and translation occur in same place, eukaryotes: transcription and translation are separated. Gene expression controlled better: nuclei in eukaryotes are very diverse. Mitochondria are special double membrane, way larger, have own dna: able to divide by fission, no other organelle can. Lynn margulis had a suggestion in 1970 origin of eukaryotic cells: endosymbiosis hypothesis (endo=inside symbiosis=living together, eukaryote envelops bacterium, ending up with organelle it acquires. Does not digest it, but uses the fact that it has a much higher way to use oxygen as electron acceptor in atp production. In turn, protects and houses the mitochondria.
