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| 88137966 | bicarbonate-carbonic acid buffer system | buffering system that controls the pH of human blood | |
| 88137967 | acid precipitation | rain, snow, or fog with a pH lower than 5.2; caused by sulfur and nitrous oxides, which are byproducts of burning fossil fuels | |
| 88137968 | vitalism | belief in a life force outside the jurisdiction of physical and chemical laws; disproved with beginning of abiotic synthesis of organic compounds | |
| 88137969 | urea | organic compound found in animals' urine: CO(NH2)2; first synthesized by Wöhler | |
| 88137970 | mechanism | physical and chemical laws govern all natural phenomena; made popular because of Miller's abiotic synthesis experiment with primeval sea water | |
| 88137971 | hydrocarbons | organic molecules consisting of only carbon and hydrogen; nonpolar bonds between C and H produce hydrophobic molecules; undergo reactions that produce lots of energy (like gasoline and fats) | |
| 88137972 | cis | on the same side | |
| 88137973 | trans | on the opposite side | |
| 88137974 | enantiomers | isomers that are mirror images of each other; usually one is biologically active while the other is not | |
| 88137975 | thalidomide | medication proscribed in the 50s and 60s; example of an enantiomer; one relieves morning sickness, the other causes severe birth defects | |
| 88137976 | steroids | organic molecule characterized by a carbon skeleton in the form of four fused rings; vary in chemical groups attached to them | |
| 88137977 | hydroxyl | functional group -OH; forms alcohols; polar and hydrophilic | |
| 88137978 | carbonyl | functional group >CO; forms ketones (if in the middle of carbon skeleton) and aldehydes (if at the end); these two groups form sugars (aldoses and ketoses); hydrophilic | |
| 88137979 | carboxyl | functional group -COOH; forms carboxylic acids; has acidic properties (charge of 1- in cells); hydrophilic | |
| 88137980 | amino | functional group -NH2; forms amines, which form amino acids; has basic qualities (charge of 1+ in cells); hydrophilic | |
| 88137981 | amino acids | compounds with both carboxyl and amino functional groups; at center is alpha carbon, partnered with H, -NH2, -R, -COOH | |
| 88137982 | sulfhydryl | functional group -SH; forms thiols; when two react together (cross-link), they help stabilize proteins (e.g., in hair); hydrophilic | |
| 88137983 | phosphate | functional group -OPO3^2-; forms organic phosphates, which are the backbone for phospholipids; hydrophilic; reacts with water, releasing energy | |
| 88137984 | methyl | functional group -CH3; forms methylated compounds, which can affect expression of genes (e.g., testosterone vs. estradiol); hydrophobic | |
| 88137985 | ATP | adenosine triphosphate; when reacts with water, becomes ADP: this reaction releases energy which can be used in a cell | |
| 88137986 | macromolecules | huge, complex organic molecules | |
| 88137987 | polymers | molecule made of a long chain of monomers; formed by condensation/dehydration, broken by hydrolysis | |
| 88150716 | enzymes | macromolecules that facilitate chemical reactions (mostly proteins); speed up dehydration when forming polymers, and hydrolysis during digestion | |
| 88150717 | carbohydrates | large biological compounds; include sugars (3 to 7 carbons long) and polymers of sugars; often form rings | |
| 88150718 | monosaccharides | simple sugar; have structural formulas that are multiples of CH2O; source of cell nutrients and raw material for forming amino acids, fatty acids, etc. | |
| 88150719 | glucose | most common monosaccharide; can form aldoses or ketoses, depending on location of carbonyl group (glucose: aldose; fructose: ketose) | |
| 88150720 | glycosidic linkage | covalent bond between two monosaccharides that forms disaccharides using dehydration | |
| 88150721 | maltose | glucose+glucose linked by glycosidic linkage; used in brewing beer | |
| 88150722 | sucrose | glucose+fructose linked by glycosidic linkage; table sugar | |
| 88150723 | lactose | glucose+galactose linked by glycosidic linkage; in milk | |
| 88150724 | starch | polysaccharide stored in plants (made of alpha glucose) within plastids; hydrolyzed when energy needed | |
| 88161855 | glycogen | polymer of glucose found in animals' liver and muscle cells; like amylopectin (branched plant starch), but more extensively branched; quickly used up if not supplemented by food intake | |
| 88161856 | cellulose | structural polysaccharide; form plant cell walls; polymer of beta glucose; these long, unbranched chains form microfibrils | |
| 88161857 | chitin | carbohydrate used by anthropods to form their exoskeletons; flexible when pure, but when exposed to calcium carbonate, hardens; also found in fungi (functions similarly to cellulose) | |
| 88161858 | lipids | too small to be called macromolecules; hydrophobic, because they consist mostly of nonpolar hydrocarbons; three types: fats, phospholipids, steroids | |
| 88161859 | fats | formed with glycerol (three carbons, each with -OH group) and fatty acids (16-18 carbons long, with carboxyl group at the end); formed by ester linkages | |
| 88161860 | ester linkage | bond between hydroxyl and carboxyl; used when forming fats | |
| 88161861 | triacylglycerol | 3 fatty acids linked to one glycerol molecule | |
| 88199776 | phospholipids | make up cell membranes; has two fatty acids attached to glycerol; third hydroxyl in glycerol is attached to phosphate; form bilayers in water, because tail is hydrophobic and head is hydrophilic; this is how cell membranes are formed | |
| 88199777 | cholesterol | component of cell membranes; help make steroids; synthesized in livers of vertebrates | |
| 88199778 | polypeptides | polymers of amino acids; one or more makes a protein | |
| 88199779 | peptide bond | covalent bond between amino group of one amino acid and carboxyl group of another; formed by dehydration; produces polypeptides | |
| 88199780 | N-terminus | amino group at the end of a polypeptide | |
| 88199781 | C-terminus | carboxyl group at the end of a polypeptide | |
| 88199782 | protein | formed from polypeptides and folded according to the bonds, which depend on the sequence of amino acids that make up the polypeptides; two kinds: globular and fibrous | |
| 88221731 | primary structure | unique sequence of amino acids in a polypeptide chain of a protein | |
| 88221732 | secondary structure | coiling (alpha helix) or folding (beta pleated sheet) that polypeptide chains take on as a result of the hydrogen bonds between the repeating amino acids in the polypeptide backbone | |
| 88221733 | alpha helix | form of secondary structure in polypeptide chains; H-bond is present between every fourth amino acid | |
| 88221734 | beta pleated sheet | form of secondary structure in poly peptide chains; two parts of the chain lie side by side, and H-bonds form between them; make up many globular proteins and some fibrous proteins | |
| 88221735 | tertiary structure | overall shape of polypeptide; results from interactions between side chains of amino acids | |
| 88221736 | hydrophobic interaction | contributes to formation of tertiary structure of proteins: amino acids with hydrophobic side chains are put at the core; held together by van der Waals interactions | |
| 88221737 | disulfide bridges | two cysteine amino acids (have -SH groups on side chains) brought close together, and forms -S-S- bridge; keeps part of the polypeptide back bone together | |
| 88221738 | quaternary structure | aggregation of polypeptides; happens when a protein is made up of more than one polypeptide | |
| 88221739 | heme | nonpolypeptide component found in hemoglobin; iron atom that binds oxygen | |
| 88231383 | denaturation | unraveling of a protein, because it is not in its natural environment, or because it is exposed to a chemical that disrupts H-bonds, ionic bonds and/or disulfide bridges; also excessive heat; sometimes can renature when denaturing agent is removed | |
| 88231384 | chaperonins | protein molecules that assist in the proper folding on other proteins; protects polypeptide while it folds | |
| 88231385 | X-ray crystallography | determines 3-D structures of proteins; first used for hemoglobin; NMR spectroscopy and bioinformetics also used to view/predict protein structures | |
| 88231386 | nucleic acids | compounds including DNA and RNA | |
| 88231387 | deoxyribonucleic acid | inherited genetic material; usually comprised of several hundred genes; each molecule of DNA makes up a chromosome; programs functions, but does not directly make cells function (proteins do that) | |
| 88270970 | ribosomes | centers of protein synthesis; mRNA conveys genetic information from nucleus to cytoplasm, and ribosomes assemble polypeptides using that information | |
| 88270971 | polynucleotides | nucleic acids (which exist as polymers); consist of nucleotides | |
| 88270972 | nucleotide | make up polynucleotides; 3 parts: nitrogenous base, pentose, and phosphate group | |
| 88270973 | nucleoside | part of nucleotide without phosphate group | |
| 88270974 | pyrimidines | 6-membered ring of carbon and nitrogen atoms; cytosine (C), thymine (T), and uracil (U) | |
| 88270975 | purines | 6-membered ring fused to 5-membered ring; adenine (A) and guanine (G) | |
| 88270976 | guanine, cytosine, adenine | members that make up nitrogenous bases in both DNA and RNA | |
| 88270977 | uracil | found only in RNA | |
| 88270978 | thymine | found only in DNA | |
| 88270979 | ribose/deoxyribose | sugar connected to nitrogenous base in nucleotides of RNA/DNA; deoxyribose lacks an oxygen; have ' (prime) to distinguish them from nitrogenous bases | |
| 88270980 | phosphodiester linkage | connects phosphate to the sugars of two nucleotides | |
| 88270981 | antiparallel | arrangement of DNA polynucleotide strands in their double helix formation; strands held together by hydrogen bonds between nitrogenous bases |
