BIOB10Y3 Lecture Notes - Lecture 1: Gemmata Obscuriglobus, Prokaryote, Paramecium
Document Summary
Prokaryotic cells arose before eukaryotic cells - fossil record. Fossil record shows that prokaryotic cells were present in rocks approx. The two types of cells related to one another b/c they share many complex traits (e. g. , very similar genetic codes, enzymes, metabolic pathways, and plasma membranes) that could not have evolved independently in different organisms. It was believed that the process gradual evolution causing eukaryotes to evolve from prokaryotes in which the organelles of the euka(cid:396)(cid:455)oti(cid:272) (cid:272)ell (cid:271)e(cid:272)a(cid:373)e (cid:373)o(cid:396)e (cid:272)o(cid:373)ple(cid:454) - wrong. Instead had to obtain preformed organic compounds from their environment. These prokaryotic ancestors are thought to have acquired the ability to form internal membrane compartments, allowing formation of a nucleus by containing the dna within an internal membrane. This development of internal membranes produces the first organism that would be considered eukaryote- like in terms of having a nucleus or other internal compartments.
