Bio 220 Principles of Physiology and Development
Bio 220 Notes Prokaryotes: 3.2 billion years ago Cell wall = peptidoglycans gram neg - lipopolysaccharides secreted outside of cell wall No internal compartments Unicellular and small (1-5 um) Most have single chromosome Transcription and translation occurs in the same location Eukaryotes: 2.1 billion years ago compartmentalization = organelles you can be more efficient with reaction vessels (concentrate functions) You can get by with fewer enzymes if you concentrate them into organelle, its cheaper Endosymbiants Mitochondria divide at their own rate, replicate independently of cell they live in Has its own DNA, circular First endosymbiants Cell size varies greatly RBC are the smallest and neurons are the largest/longest Plasma Membrane