BIOL 1020 Lecture Notes - Molecular Clock, Gene Duplication, Medical Genetics
Document Summary
Molecular systematics: dna sequences can provide derived homologies just like morphological traits can. Orthologous genes: a product of speciation: widespread and extend across, gene number and the complexity of an organism are not strongly linked. Genes in complex organisms appear to be very versatile: some genes can perform many functions. Molecular evolution and the tree of life: early taxonomy: two kingdoms, plants, animals. Late 1960s: five kingdoms: monera (prokaryotes) some prokaryotes differ from each other as they do from eukaryotes, protista, plantae, fungi, animalia, recent: three domains, bacteria (previously monera, archaea (previously monera) Horizontal gene transfer is the movement of genes from one genome to another. Horizontal gene transfer occurs by exchange of transposable elements and plasmids, viral infection, and fusion of organisms. Horizontal gene transfer complicates efforts to build a tree of life. Parents and offsprings is considered vertical: the ring of life, some researchers suggest that eukaryotes arose as a fusion between a bacterium and archaen.
