Notes and VocabularyDalton: measure of mass of atoms and subatomic particles; same as atomic mass unit, amu•Electronegativity: attraction of given atom for electrons of covalent bond•Cation: positively charged ion•Anion: negatively charged ion•Hydrogen bond: weak attraction between hydrogen atom carrying partial positive charge and electronegative atom•van der Waals interactions: ocurr between transiently positive and negative regions of molecules, orbital electrons brief shift to one side of atom or molecule•Chapter 2Cohesion: linking together of like molecules, often by hydrogen bonds, water transport in plants•Adhesion: clinging of one substance to another, such as water to plant cell walls by means of hydrogen bonds•Colloid: mixture made up of liquid and particles that b/c of large size remain suspended rather than dissolved in that liquid•Hydronium ion: •Chapter 3Water is polar, Hydrocarbons are non-polar•Structural isomers: one of several compounds that have same molecular formula but differ in covalent arrangements of atoms•Cis-trans isomer: one of several compounds that have same molecular formula and covalent bonds between atoms but differ in spatial arrangements of atoms owing to inflexibility of double bonds; formerly called geometric isomer•Enantiomer: one of two compounds that are mirror images of each other and that differ in shape due to presence of asymmetric carbon•ATP: adenosine triphosphate•Chapter 4Ribosomes are attached to cytoplasmic side of nuclear envelope's outer membrane which is continuous with rough ER•Cell fractionation: disruption of cell and separation of its parts by centrifugation at successively higher speeds•Cytosol: semifluid portion of cytoplasm where subcellular components are suspended•Nucleoid: non-membrane-bounded region in prokaryotic cell where DNA is concentrated•Nuclear lamina: netlike array of protein filaments that lines inner surface of nuclear envelope and helps maintain shape of nucleus•Chromatin: complex of DNA and proteins that makes up eukaryotic chromosomes, when cell is not dividing chromatin exists in its dispersed form as mass of very long thin fivers that are not visible with light microscope•Nucleolus: specialized structure in nucleus consisting of chromosomal regions containing ribosomal RNA genes along with ribosomal proteins imported from cytoplasm; site of rRNA synthesis ad ribosomal subunit assembly•Endomembrane system: includes plasma membrane, nuclear envelope, smooth and rough ER, Golgi apparatus, lysosomes, vesicles and vacuoles•Cisternae: flattened membranous sacs that are part of the Golgi apparatus, trans-cis•Cristae: infolding of inner membrane of mitochondrion, inner membrane houses electron transport chains and molecules of ATP synthase•Contractile vacuole: membranous sac that helps move excess water out of certain freshwater protists•Thylakoids: flattened, membranous sac inside chloroplast, often exist in stacks called granathat are interconnected; membranes contain molecular "machinery" used to convert light energy to chemical energy•Stroma: dense liquid w/I chloroplast surrounding thylakoid membrane, contains ribosomes and DNA, involved in synthesis of organic molecules from carbon dioxide and water•Peroxisome: organelle containing enzymes that transfer hydrogen atoms from various substrates to oxygen, producing then degrading hydrogen peroxide •Microtubule: hollow rod composed of tubulin proteins that makes up part of cytoskeleton in all eukaryotic cells, grows out from centrosome, functions: maintenance of cell shape •Chapter 6Chapter 2: The Chemical Context of LifeChapter 3: Water and LifeChapter 4: Carbon and Molecular Diversity of LifeChapter 6: A Tour of the CellImportant Chemical Groups pg 64-65Hydroxyl Carbonyl Carboxyl Amino Sulfhydryl Phosphate Methyl QuestionsWhat is the difference between the cytosol and the cytoplasm?Do all plastids have their own DNA or only chloroplasts?Lecture Topic 0 ReadingsThursday, September 5, 201312:58 PM BioG 1440 Page 1all eukaryotic cells, grows out from centrosome, functions: maintenance of cell shape (compression-resisting "girders"), cell motility (cilia and flagella), chromosome movements in cell division, organelle movementsMicrofilaments: two intertwined strands of actin, each a polymer of actin subunits, functions: maintenance of cell shape (tension-bearing elements), changes in cell shape, muscle contraction, cytoplasmic streaming, cell motility (pseudopodia), cell division (cleavage furrow formation)•Intermediate filaments: fibrous proteins supercoiled into thicker cables, composed of one of several different proteins (such as keratins), depending on cell type, functions: maintenance of cell shape (tension-bearing elements), anchorage of nucleus and certain other organelles, formation of nuclear lamina)• BioG 1440 Page 2Catabolic vs. anabolic pathway: metabolic pathway that releases energy by breaking down complex molecules to simpler molecules•Energy: capacity to cause change•1st law of thermodynamics: principle of conservation of energy, energy can neither be created nor destroyed, only transferred or transformed•2nd law of thermodynamics: every energy transfer or transformation increases entropy of universe•Free energy: ΔG, portion of biological system's energy that can perform work when temperature and pressure are uniform throughout system, more free energy higher ΔG•Exergonic reaction: spontaneous, net release of energy, ΔG is negative•Endergonic reaction: non-spontaneous, absorbs free energy from environment, ΔG is positive•Catalyst: chemical agent that selectively increases rate of reactions w/o being consumed by reaction, lowers activation energy•Increased temperature increases enzyme activity until denature is possible, denaturing disrupts hydrogen bonds, ionic bonds and other weak interactions•Cofactor: nonprotein molecule or ion that is required for proper functioning of enzyme, can be permanently bound to active site or may bind loosely and reversibly along with substrate during catalysis•Coenzyme: organic cofactor molecule, most vitamins function as coenzymes in metabolic reactions•Competitive inhibitor: substance that reduces activity of enzyme by entering active site in place of substrate, whose structure it mimics•Noncompetitive inhibitor: substance that reduces activity of enzyme by binding to location remote