Atoms Molecules and Chemical Bonds Covalent share electrons can be polar or non polar Polar electrons shared unequally very different electronegativity Non Polar electrons shared equally same ions or very similar electronegativity Ionic loses gains electrons between negative and positive ion Van der Waals weak ever changing positive negative regions enable molecules to stick together Hydrogen Bond weak slightly positive H of polar molecule is attracted to polar negative ion of another molecule region Soluble in water polar Element a single atom Compound 2 or more atoms of the same element Molecule 2 or more atoms of 1 or more elements Atomic number number of protons determines what element it is Ion charge element Isotope element with different numbers of neutrons different masses Carbon Functional Groups and Polymers Isomers same number of elements of same atoms but different structures Structural different covalent arrangement of atoms Cis trans same covalent bonds but different spatial arrangements rotation Enantiomers mirror images asymmetric carbon Only 1 biologically active b c it can only bind to specific molecules in an organism Functional Groups Hydroxyl OH Alcohols polar hydrogen bonds Ethanol Carbonyl CO 2x bond Ketones Aldehydes Acetone Proponal can be structural isomers found in sugars Carboxyl COOH 2x bond btwn CO carboxylic organic acids acetic acid acid donates H b c of polar covalent bond carboxylate 1 Amino NH amines glycine amino acid carboxyl amine base picks up H 1 Sulfhydryl SH Thiols Cysteine 2 can react covalent bond cross linking Phosphate OPO 2 Organic phosphates Glycerol phosphates release energy Methyl CH non reactive methylated compounds 5 Methyl cytidine addition of to DNA affects gene expression arrangement of in sex hormones affects shape Shape determines whether or not a molecule will fit into an active site Lock and key Polymerization Dehydration condensation Short polymer unlinked monomer come together longer polymer releases water bond Degradation Hydrolysis Long polymer breaks into shorter polymer and monomer requires water Carbohydrates Cellulose plant support Trioses glycolysis pentoses nucleic acid hexosescellular respiration Hydrophilic joints lubricated Carbonyl group and many hydroxyl groups Disaccharide 2 monosaccharides joined by glycosidic linkage Polysaccharides macromoles Chain hydrogen bonds ring how the hydroxyl group is orientated determines alpha or beta bond Nucleic Acids Nucleotides phosphate group sugar pentose nitrogenous base DNA deoxyribose RNA ribulose Pyrimidines Cytosine Thymine Uracil Purines Adenine Guanine Lipids All do not dissolve well in water Not true polymers Mostly fatty acids glycerol O is not abundant would make it polar soluble Fatty Acids Hydrophilic head HO hydrophobic tail CH Saturated all single bonds can pack van der waals Unsaturated a double bond Polysaturated many double bonds Tryglyceride 3 fatty acids linked to one glycerol molecule Phospholipid Nitrogen containing head and phosphate group hydrophilic Glycerol fatty acid tail hydrophobic Amphipathic When interacting with water forms bilayer or micelle Sterols Cholesterol Proteins Enzyme CT muscle contraction storage signaling receptors transportation antibodies Amino Acid Water and pH H OH 10 pH log H H 10 pH pH increases by 1 H content decreases 10 fold pH decreases by 1 H content increases 10 fold Strong acids bases dissociate completely in water NH4 NaOH Weak acids base can add reduce H ions frequently carbonic acid Reversible reaction reactants react with other reactants form products products react with other products to form the reactants Reversibly release and accept H ions A buffer will not change very quickly but after drastically changing the concentration the pH will fall raise Changing pH in the tissues molecules causes certain molecules minerals to react and take a different form that is harmful or not helpful to tissues Molarity concentration of solute in moles per liter of solution