Biology 1002B Lecture Notes - Lecture 11: Southern Blot, Nuclear Membrane, Central Dogma Of Molecular Biology
Document Summary
Bio 1002b - lecture 11 endosymbiosis & lateral gene. Where did the nucleus and nuclear envelope come from: infolding of plasma membrane in ancestral bacterium. Anaerobic bacterium engulfs aerobic bacterium which evolves into modern day mitochondria. Subset of those bacteria engulf cyanobacteria, which evolve into modern day chloroplasts. Mito/chloro and their presumed ancestors look the same: formation/division. Mito/chloro and bacteria both divide/form by binary fission. Unlike ribosomes, which are assembled by rna and proteins: electron transport chains. Mito/chloro are only organelles that have own etc, like bacteria: genomes. Mito/chloro have own dna: transcription/translation machinery. Mito/chloro can perform central dogma process on their own. Modern endosymbiont genomes are greatly diminished: chloroplast: 200 kb, mitochondrion: 16 kb, nucleus: 120 000 kb. Typical e. coli genome = 5000 kb, 5000 genes. Chloroplast genome: 99 genes in 203 kb. Genes don"t have to code for proteins, they can code for rna that isn"t translated into proteins (functions by itself)
