front 1 matter | back 1 all tangible materials that occupy space and have mass
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front 2 atom | back 2 the smallest particle of an element to retain all the properties of that element.
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front 3 proton | back 3 a elementary particle that carries a postive charge. It is identical to the nucleus of the hydrogen atom.
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front 4 neutrons | back 4 a electrically neutral particle in the nuclei of all atoms except hydrogen.
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front 5 electrons | back 5 a negatively charged subatomic particle that is distributed around the nucleus in an atom.
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front 6 nucleus | back 6 the central core of an atom, composed of protons and neutrons
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front 7 atomic number (AN) | back 7 a measurement that reflects the number of protons in an atom of a particular element.
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front 8 mass number (MN) | back 8 measurement that reflects the number of protons and neutrons in an atom of a particular element.
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front 9 Isotope | back 9 a version of an element that is virtually identical in all chemincal properties to another version except that their atoms have slightly different atomic masses.
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front 10 atomic mass or weight | back 10 the average of the mass numbers of all the isotopic forms for a particular element.
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front 11 orbitals | back 11 the pathways of electrons as they rotate around the nucleus of an atom.
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front 12 molecule | back 12 little mass: a distinct chemical substance that results from the combination of two or more atoms.
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front 13 compounds | back 13 molecules that are a combination of two or more different elements.
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front 14 molecular weight (MW) or formula mass | back 14 the weight of a molecule; which is calculated fromt he sum of all of the atomic masses of the atoms it contains.
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front 15 chemical bonds | back 15 a link formed between molecules when two or more atoms share, donate, or accept electrons.
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front 16 valence | back 16 the combining power of an atom based upon the number of electrons it can either take on or give up.
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front 17 Covalent bonds | back 17 cooperative valence - a chemical bond formed by the sharing of electrons between two atoms.
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front 18 polar | back 18 term to describe a molecule with an asymmetrical distribution of charges. Such a molecule has a negative pole and a positive pole.
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front 19 nonpolar | back 19 a term used to describe an electrically neutral molecule formed by the covalent bonds between atoms that have the same or similar electronegativity.
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front 20 ionic bonds | back 20 a chemical bond in which electrons are transferred and not shared between atoms.
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front 21 ionization | back 21 the aqueous dissociation of an electrolyte into ions.
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front 22 ion | back 22 an unattached, charged particle.
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front 23 cations | back 23 a positively charged ion, that migrates toward the negative pole or cathode of an electrical field.
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front 24 anions | back 24 a negatively charged ion that migrates toward the positive pole or anode.
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front 25 electrolytes | back 25 any compound that ionizes in solution and conducts current in an electrical field.
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front 26 hydrogen bond | back 26 a weak chemical bond formed by the attraction of forces between molecules or atoms - in this case, hydrogen and either oxygen or nitrogen. In this type of bond, electrons are not shared, lost or gained.
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front 27 Vander Waals forces | back 27 weak molecular interactions similar to hydrogen bonds that play major roles in the shape and function of biological molecules.
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front 28 oxidation reduction reaction (REDOX) | back 28 Redox-reactions, in which paired sets of molecules participate in electron transfers.
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front 29 reducing agent | back 29 an atom such as sodium that can donate electrons and thereby reduce another atom.
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front 30 oxidizing agent | back 30 an atom that can receive extra electrons and thereby oxidize another molecule.
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front 31 chemical reactions | back 31 changes in the composition of the matter that molecules, including those in cells. These changes generally involve the breaking and making of bonds and the rearrangement of atoms.
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front 32 reactants | back 32 molecules entering or starting a chemical reaction.
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front 33 products | back 33 The substances that result from the reaction.
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front 34 chemical equation | back 34 Used by chemists and biologists as a form of shorthand to summarize the content of a reaction.
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front 35 synthesis reaction | back 35 the reactants bond together in a manner that produces an entirely new molecule.
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front 36 exchange reactions | back 36 the reactants trade portions between each other and release products that are combinations of the two.
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front 37 decomposition reactions | back 37 the bonds on a single reactant molecule are permanently broken to release two or more product molecules.
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front 38 catalysts | back 38 a substance that alters the rate of a reaction without being consumed or permanently changed by it. In cells, enzymes are catalysts.
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front 39 solution or solute | back 39 a mixture of one or more substances (solutes) that cannot be separated by filtration or ordinary settling.
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front 40 solvent | back 40 a dissolving medium.
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front 41 hydrated or hydration | back 41 the addition of water as in the coating of ions with water molecules as ions enter into aqueous solution.
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front 42 hydrophilic | back 42 the property of attracting water or molecules that attract water to their surface.
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front 43 hydrophobic | back 43 the property of repelling water or molecules that repel water.
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front 44 amphipathic | back 44 (mphi, both) relating to a compound that has contrasting characteristics, such as hydrophilic - hydrophobic or acid-base.
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front 45 concentration | back 45 the expression of the amount of a colute dissolved in a certain amount of colvent. It may be defined by weight, volume or percentage.
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front 46 hydrogen ion | back 46 is positively charged because it is essentially a hydrogen that has lost its electron.
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front 47 hydroxide ion | back 47 is negatively charged because it remains in possession of that electron.
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front 48 acidic | back 48 a solution with a pH value below 7 on the pH scale.
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front 49 basic | back 49 a solution with a pH value above 7 on the pH scale.
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front 50 alkaline | back 50 another term used interchangeably with basic.
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front 51 pH | back 51 The symbol for the negative logarithm of the H ion concentration; p (power) or [H+]10. A system for rating acidity and alkalinity.
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front 52 neutrality | back 52 Is the midpoint (pH 7) of the pH scale.
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front 53 neutralization | back 53 the process of combining an acid and base until they reach a balanced proportion, with a pH value close to 7.
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front 54 metabolism | back 54 a general term referring to the totality of chemical and physical processes occurring in the cell.
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front 55 inorganic chemicals | back 55 molecules that lack the basic framework of the elements of carbon and hydrogen.
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front 56 organic chemicals | back 56 molecules that contain the basic framework of the elements carbon and hydrogen.
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front 57 functional groups | back 57 in chemistry, a particular molecular combination that reacts in predictable ways and confers particular properties on a compound.
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front 58 biochemistry | back 58 the study of organic compounds produced by (or components of) living things. The four main categories of biochemicals are carbohydrates, lipids, proteins, and nucleic acid.
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front 59 macromolecules | back 59 large, molecular compounds assembled from smaller subunits, most notably biochemicals.
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front 60 monomers | back 60 a simple molecule that can be linked by chemical bonds to form larger molecules.
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front 61 polymers | back 61 a macromolecule made up of a chain of repeating units. Ex: starch, protein and DNA.
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front 62 carbohydrate | back 62 a compound containing primarily carbon, hydrogen, and oxygen in a 1:2:1 ratio.
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front 63 ketones or aldehydes | back 63 a sugar such as glucose with a terminal cabonyl group bonded to a hydrogen and another carbon.
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front 64 saccharide | back 64 scientific term for sugar. Refers to a simple carbohydrate with a sweet taste.
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front 65 monosaccharide | back 65 a simple sugar such as glucose that is a basic building block for more complex carbohydrates.
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front 66 disaccharide | back 66 a sugar containing two monosaccharides.
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front 67 polysaccharide | back 67 a carbohydrate that can be hydrolyzed into a number of monosaccharides.
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front 68 hexose | back 68 a 6-carbon sugar such as glucose and fructose.
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front 69 pentose | back 69 a monosaccharide with five carbon atoms per molecule. Ex: arabinose, ribose and xylose.
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front 70 glucose | back 70 one of the carbohydrates commonly referred to as sugars. Glucose is characterized by its 6-carbon structure.
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front 71 frutose | back 71 one of the carbohydrates commonly referred to as sugars. Fructose is commonly fruit sugars.
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front 72 lactose | back 72 one of the carbohydrates commonly referred to as sugars. Lactose is commonly found in milk.
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front 73 maltose | back 73 one of the carbohydrates referred to as sugars. A fermentable sugar formed from starch.
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front 74 sucrose | back 74 one of the carbohydrates commonly referred to as sugars. Commonly table or cane sugar.
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front 75 glycosidic bonds | back 75 a bond that joins monosaccharides to form disaccharides and polymers.
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front 76 dehydration synthesis | back 76 during the formation of a carbohydrate bond, the step in which one carbon molecule gives up its OH group and the other loses the H from its OH group, thereby producing a water molecule. This process is common to all polymerization reactions.
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front 77 cellulose | back 77 a long, fibrous polymer composed of ß-glucose; one of the most common substances on earth.
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front 78 agar | back 78 a polysaccharide found in seaweed and commonly used to prepare solid culture media.
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front 79 chitin | back 79 a polysaccharide similar to cellulose om chemical structure. This polymer makes up the horny substance of the exoskeletons of arthropods and certain fungi.
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front 80 peptidoglycan | back 80 a network of polysaccharide chains cross-linked by short peptides that forms the rigid part of the bacterial cell walls. Gram-negative bacteria have a smaller amount of this rigid structure than do gram-positive bacteria.
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front 81 lipopolysaccharide (LPS) | back 81 a molecular complex of lipids and carbohydrate found in the bacterial cell wall. The lipopolysaccharide (LPS) of gram negatve bacteria is an endotoxin with generalized pathologic effects sich as fever.
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front 82 glycocalyx | back 82 a filamentous network of carbohydrate-rich molecules that coats cells.
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front 83 starch or glycogen | back 83 Polysaccharides are usually stored by cells in the form of glucose polymers that are readily tapped as a source of energy and other metabolic needs.
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front 84 hydrolysis | back 84 a process in which water is used to break bonds in molecules. Usually occurs in conjunction with an enzyme.
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front 85 lipid | back 85 a term used to describe a variety of substances that are not soluble in polar solvents such as water but will dissolve in nonpolar solvents such as benzene and chloroform. Lipids include triglycerides, phospholipids, steroids, and waxes.
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front 86 triglyceride | back 86 a type of lipid composed of a glycerol colecule bound to three fatty acids.
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front 87 fatty acids | back 87 long chain unbranched hydrocarbon molecules with a caboxyl group (COOH) at one end that is free to bind to the glycerol.
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front 88 ester bond | back 88 a covalent bond formed by reacting carboxylic acid with an OH group.
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front 89 phospholipids | back 89 a class of lipids that compose a major structural component of cell membranes.
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front 90 cholesterol | back 90 best known member of a group of lipids called steroids. Cholesterol is commonly found in cell membranes and animal hormones.
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front 91 proteins | back 91 predominant organic molecule in cells, formed by long chains of amino acids.
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front 92 amino acids | back 92 the building blocks of protein. Amino acids exist in 20 naturally occurring forms that impact different characteristics to the various proteins they compose.
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front 93 peptide bond | back 93 the covalent union between two amino acids that forms between the amine group of one and the carboxyl group of the other. The basic bond of proteins.
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front 94 peptide | back 94 molecule composed of short chains of amino acids, such as a dipeptide (two amino acids), a tripeptide (three) and a tetrapeptide (four).
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front 95 polypeptide | back 95 a relatively large chain of amino acids linked by peptide bonds.
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front 96 primary(1°)structure | back 96 Initial protein organization described by type, number, and order of amino acids in the chain. The primary structure varies extensively from protein to protein.
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front 97 secondary(2°)structure | back 97 protein structure that occurs when the functional groups on the outer surface of the molecule interact by forming hydrogen bonds. These bonds cause the amino acid chain either to twist, forming a helix, or to pleat into an accordion pattern called a ß-pleated sheet.
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front 98 tertiary(3°)structure | back 98 protein structure that results from additional bonds forming between functional groups in a secondary structure, creating a three dimensional mass.
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front 99 quaternary(4°)structure | back 99 most complex protein structure characterized by the formation of large, multiunit proteins by more than one of the polypeptides. This stucture is typical of antibodies and some enzymes that act in cell synthesis.
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front 100 enzymes | back 100 a protein biocatalyst that facilitates metabolic reactions.
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front 101 antibodies | back 101 a large protein molecule evoked in response to an antigen that interacts specifically with that antigen.
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front 102 deoxyribonucleic acid (DNA) | back 102 the nucleic acid often referred to as the "double helix." DNA carries the master plan for an organism's herdity.
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front 103 ribonucleic acid (RNA) | back 103 the nucleic acid responsible for carrying out the hereditary program transmitted by an organism's DNA.
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front 104 nucleotide | back 104 the basic structure unit of DNA and RNA; each nucleotide consists of a phosphate, a sugar (ribose in RNA, deoxyribosein DNA), and a nitrogenous base such as adenine, guanine, cytosine, thymine (DNA only) or uracil (RNA only).
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front 105 nitrogen base | back 105 a ringed compound f which pyrimidines and purines are types.
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front 106 adenine (A) | back 106 one of the nitrogen bases found in DNA and RNA, with a purine form.
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front 107 guanine (G) | back 107 one of the nitrogen bases found in DNA and RNA in the purine form.
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front 108 thymine (T) | back 108 one of the nitrogen bases found in DNA but not in RNA. Thymine is in a pyrimidine form.
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front 109 cytosine (C) | back 109 One of the nitrogen bases found in DNA and RNA, with a pyrimindine form.
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front 110 uracil (U) | back 110 one of the nitrogen bases in RNA but not in DNA. Uracil is in a pyrimindine form.
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front 111 replication | back 111 in DNA synthesis, the semiconservative mechanisms that ensure precise duplication of parent DNA strands.
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front 112 adenosine triphosphate (ATP) | back 112 a nucleotide that is the primary source of energy to cells.
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