BIOL 1000 Study Guide - Midterm Guide: Cell Envelope, Nucleoid, Cell Membrane
Document Summary
All cells are bounded by a plasma membrane; have a cytosol containing metabolites, coenzymes, inorganic ions, and enzymes; and have a set of genes contained within a nucleoid (bacteria and archaea) or nucleus (eukaryotes). All organisms require a source of energy to perform cellular work. Phototrophs obtain energy from sunlight; chemotrophs obtain energy from chemical fuels, oxidizing the fuel and passing electrons to good electron acceptors: inorganic compounds, organic compounds, or molecular oxygen. Bacterial and archaeal cells contain cytosol, a nucleoid, and plasmids, all within a cell envelope. Eukaryotic cells have a nucleus and are multicompartmented, with certain processes segregated in specific organelles; organelles can be separated and studied in isolation. Cytoskeletal proteins assemble into long filaments that give cells shape and rigidity and serve as rails along which cellular organelles move throughout the cell. Supramolecular complexes held together by noncovalent interactions are part of a hierarchy of structures, some visible with the light microscope.
