Biology 1002B Lecture Notes - Fall 2018 Lecture 13 - Ribosomal RNA, Electron acceptor, Advantageous
Document Summary
Endomembrane system: infolding of the plasma membrane may have derived the nuclear envelope and endoplasmic reticulum from an ancestral bacterium. The plasma membrane lipid composition must still be similar to that of the ancestral bacterium. Endosymbiosis: modern-day mitochondria and chloroplasts are derived from free living prokaryotic cells. Mitochondria may be descendants of aerobic bacterium. A subset of eukaryotic lineages also took up chloroplasts from cyanobacterium. The progenitor of the modern chloroplast is cyanobacteria. Morphology (chloroplasts and mitochondria look like aerobic/cyano-/ bacteria) Formation/division (no cellular instructions on how to make chloroplast or mitochondria - they come from already produced chloroplasts or mitochondria) You don"t make more mitochondria by gene expression, you cause them to divide (similar to bacterial division) Over evolutionary time some genes from the mitochondrial genome (or chloroplast) have moved to the nucleus. This movement of genetic information is still occurring. This is termed lateral or horizontal gene transfer.
