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104 Cards in this Set
- Front
- Back
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MATTER
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Any physical substance which occupies space, has mass, and can be perceived by one or more senses; composed of atoms of various chemical elements.
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ENERGY
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The capacity for performing work. Chemical energy is derived from the ability of atoms and molecules to participate in the making or breaking of chemical bonds.
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POTENTIAL ENERGY
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The stored energy of a body or system, i.e., energy which is not kinetic, i.e., energy due to configuration; examples of potential energy include energy stored in a bent spring, or a body suspended a given distance above the earth and acted on by gravity.
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KINETIC ENERGY
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The active energy of a body, i.e., the energy it has as a result of being in motion; i.e., energy which is not potential; examples of kinetic energy include moving bodies, heat transference, electric currents, etc.
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CHEMICAL ELEMENT
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A substance composed of atoms having an identical number of protons in each nucleus and an equal number of electrons in its outer shells. Elements cannot be reduced to simpler substances by normal chemical means. Each element has its own unique chemical properties. Elements are organized in the Periodic Table by their atomic numbers.
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ATOM
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A unit of matter, the smallest unit of an element, having all the characteristics of that element and consisting of a dense, central, positively charged nucleus surrounded by a system of electrons. The entire structure characteristically remains undivided in chemical reactions except for limited removal, transfer, or exchange of certain electrons.
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ELECTRON
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A stable sub-atomic particle with a negative charge. Electrons are located in orbitals or electron shells at some distance from the nucleus of their respective atoms. A flow of electrical current consists of the movement of many electrons. Atoms of a given element contain the same number of protons as electrons.
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NUCLEUS (ATOMIC)
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he dense central core of an atom which contains the protons and neutrons.
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PROTON
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A stable sub-atomic particle with a positive charge. Protons are located in the nucleus of their respective atoms along with neutrons. Atoms of a given element contain the same number of protons as electrons.
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NEUTRON
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A stable sub-atomic particle with a neutral charge. Neutrons are located in the nucleus of their respective atoms along with protons. Atoms of a given element contain a variable number of neutrons (isotopes), generally equal to or nearly the same as the number of protons or electrons.
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ATOMIC NUMBER
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The number which identifies a particular element by giving the number of protons, e.g., carbon has 6 protons and the atomic number 6.
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MASS
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The quantity of matter which a body contains, irrespective of its bulk or volume. (A property of matter equal to the measure of an object's resistance to changes in either the speed or direction of its motion. The mass of an object is not dependent on gravity and therefore is different from but proportional to its weight.) The amount of mass in a material is equivalent to the sum of all the subatomic particles (protons, neutrons, and electrons) in the material.
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MASS NUMBER
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The number which identifies a particular isotope of any element by giving the sum of number of protons and neutrons, e.g., carbon 14 = 14C contains 6 protons and eight neutrons.
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ISOTOPE
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One of two or more atoms with the same atomic number but with different numbers of neutrons, e.g., carbon 12 = 12C and carbon 14 = 14C.
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RADIOACTIVE ISOTOPE
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Certain isotopes are unstable and transform (decay) into different isotopes losing protons or neutrons and are termed radioactive.
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ELECTRON SHELL= ORBITAL
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The wave function of an electron in an atom or molecule, indicating the electron's probable location at a distance from the atomic nucleus; the outer shell or orbital of a given element contains a characteristic number of electrons and the number of those electrons determines how this atom will bond with other atoms.
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VALENCE
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The combining capacity of an atom or radical determined by the number of electrons that it will lose, add, or share when it reacts with other atoms; represented by positive or negative integers, e.g., 1+, 2+, 1-, etc.
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MOLECULE
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MOLECULE - A substance formed by the chemical combination (chemical bonding, usually covalent or ionic bonding) of two or more atoms (of the same or different elements); the smallest particle of a chemical compound that retains the chemical properties of the compound. [A stable molecule occurs when the total energy of the combination has a lower energy state than the separated atoms.]
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COMPOUND
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COMPOUND - A substance formed by the chemical combination (chemical bonding, usually covalent or ionic bonding) of two or more atoms of different elements. [A stable compound occurs when the total energy of the combination has a lower energy state than the separated atoms.]
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INORGANIC COMPOUND
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INORGANIC COMPOUND - Any example of the large series of molecules which do not contain carbon atoms (other than a few exceptions such as carbon monoxide, carbon dioxide, and carbides); biologically important examples of inorganic compounds include water, acids, bases, salts, and electrolytes
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ORGANIC COMPOUND
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ORGANIC COMPOUND - Any example of the large series of biological molecules which always contain carbon, almost always contain both hydrogen and oxygen, and sometimes contain other elements such as nitrogen, sulfur, phosphorus; biologically important examples of organic compounds include carbohydrates, lipids, proteins, and nucleic acids.
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CHEMICAL ENERGY
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CHEMICAL ENERGY - The usable power (energy*) liberated by a chemical reaction when chemical bonds are broken or the usable power (energy*) absorbed in the formation of a chemical compound when new chemical bonds are made.
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CHEMICAL REACTION
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he process in which one or more substances (elements, ions, or molecules), the "reactants," are changed into others, the "products;" there is no change in mass nor in the number of atoms of specific elements, but the arrangements of the atoms, controlled by chemical bonds, are changed; there are also always changes in the energy states of some or all of the participants and some chemical energy is lost to the environment as waste heat, i.e., the energy transformations are not 100% efficient. EX- DEHYDRATION SYNTHESIS DECOMPOSITION REACTION SYNTHESIS REACTION HYDROLYSIS OXIDATION REDUCTION
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ACTIVATION ENERGY
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he process in which one or more substances (elements, ions, or molecules), the "reactants," are changed into others, the "products;" there is no change in mass nor in the number of atoms of specific elements, but the arrangements of the atoms, controlled by chemical bonds, are changed; there are also always changes in the energy states of some or all of the participants and some chemical energy is lost to the environment as waste heat, i.e., the energy transformations are not 100% efficient.
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EXERGONIC
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The adjective used to describe those (usually catabolic) chemical reactions in which the potential chemical energy ("free energy") of the products is less than the potential chemical energy ("free energy") of the reactants and the rest of the energy has been released from the reaction as some form of kinetic energy, always including the release of some waste heat.
Reactant(s) ↔ Products(s) + energy + waste heat |
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ENDERGONIC
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The adjective used to describe those (anabolic) chemical reactions in which the potential chemical energy ("free energy") of the products is greater than the potential chemical energy ("free energy") of the reactants and, therefore, energy has to be provided to the reaction as some form of kinetic energy input in order for the reaction to occur. [Note: because all chemical reactions are less than 100% efficient, the reaction will also include the release of some waste heat.]
Reactant(s) + energy ↔ Products(s) + waste heat |
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ACID
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A substance which dissolves in water to release H+ ions, and some corresponding negative ion(s); a proton donor in chemical reactions.
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ACIDIC SOLUTION
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A mixture, a solution, of water and various chemicals, some of which are able to release hydrogen ions (H+) into the mixture/solution, such that the pH of the solution is less than 7; such solutions have a great concentration of hydrogen ions (H+) than hydroxyl ions (OH-).
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BASE
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A substance which dissolves in water to release OH- ions, and some corresponding positive ion(s); a proton acceptor in chemical reactions.
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BASIC= ALKALINE SOLUTION
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A mixture, a solution, of water and various chemicals, some of which are able to release hydroxyl ions (OH-) into the mixture/solution, such that the pH of the solution is greater than 7; such solutions have a great concentration of hydroxyl ions (OH-) than hydrogen ions (H+).
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Ph
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pH is a mathematical expression indicating how acidic or alkaline a water-based solution is. The pH scale extends from 0 (most acid) to 14 (most basic = alkaline). The pH of a solution is the negative log of the hydrogen ion concentration.
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BUFFER
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A chemical or mixture of chemicals, usually a weak acid or base and its corresponding salt, which minimizes change in the acidity of a solution, the pH, when an acid or base is added to the solution.
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SALT
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The product of any reaction in which an acid and a base combine to yield water and various ions or electrolytes; these compounds usually crystallize when dry.
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SOLUTION
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Any homogeneous mixture of two or more substances in which the various solutes are dissolved in the solvent in such a way that each individual atom or molecule of the solute is independently dissolved in the solvent substance; such a mixture may be in any physical phase, solid, liquid, or gas.
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SOLVENT
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Any substance in which other substance may be dissolved, forming a solution, a colloid, or a suspension; generally, the proportion of the solvent exceeds the proportion(s) of the solute(s); two broad classes are recognized, those, such as water, which have polar covalent bonds and readily dissolve other substances which are charged or partially charged, and those, such as oils, which have nonpolar covalent bonds and readily dissolve other uncharged substances; such a substance may be in any physical phase, solid, liquid, or gas, but typically they are liquids.
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SOLUTE
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Any substance dissolved in another substance, usually the component(s) of a solution present in the lesser amount(s); the dissolved substance(s) in a solution; the component of a solution may change its state, e.g., the gas, oxygen or the solid, sodium chloride, enter the liquid state formed by the solvent when dissolved in water. [Note: the degree to which a solvent dissolves a given solute is termed the solubility of that solute in that solvent.]
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POLAR SOLVENT
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Any compound, e.g., water (H2O) or liquid ammonia (NH3), which contains some (or all) polar covalent bonds, such that the molecule contains two or more regions which carry partial electrical charges, and, as a result, is capable of dissolving other charged or partially charged ("polar") materials such as other molecules with polar covalent bonds or charged ions. [Note: polar solvents are attracted to their solute particles by hydrogen bonds.]
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NON POLAR SOLVENT
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Any compound, e.g., gasoline or benzene, which contains primarily non-polar covalent bonds, such that the molecule is neutral or uncharged (contains no regions which carry partial electrical charges), and, as a result, is capable of dissolving other uncharged ("nonpolar") materials such as other molecules with nonpolar covalent bonds, e.g., lipids. [Note: nonpolar solvents are attracted to their solute particles by hydrophobic bonds = van der Wals attractions.]
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SUSPENSION
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A system (a mixture of chemicals) in which microscopically visible bouyant particles are dispersed (as opposed to dissolved as individual molecules) throughout a less dense liquid or gas from which they are easily filtered but not easily settled out of solution by gravity because of system viscocity or molecular interactions. [Note: examples include milk and blood plasma.]
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COLLOID=COLLOIDAL SUSPENSION
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A system (a mixture of chemicals) in which microscopically/macroscopically visible particles (which are approximately 10 to 10,000 angstroms in size) are dispersed (as opposed to dissolved as individual molecules) throughout a less dense liquid or gas; such particles may be filtered (with the appropriate small pore size filter) and can be settled out of solution by gravity if left undisturbed for a sufficient period of time. [Note: examples include whole blood and smoke.]
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HEAT CAPACITY
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The amount of heat required to raise the temperature of one mole or one gram of a substance by one degree Celsius without a change of phase. aka - thermal capacity and specific heat
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CHEMICAL BOND
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Any of the several forces or mechanisms, primarily relationships between electrons, by which atoms or ions are bound in a molecule or crystal; examples include the covalent bond, ionic bond, hydrogen bond, hydrophobic bond = van der Waals attraction and metallic* bond. (*The chemical bond characteristic of metals, in which mobile valence electrons are shared among atoms in a usually stable crystalline structure). [A stable compound occurs when the total energy of the combination has a lower energy state than the separated atoms.]
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COVALENT BOND
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A strong attraction between atoms because they are sharing one or more outer shell valence electrons; much chemical energy is required to create this sharing and much energy will be released if it is broken; it is the strongest of the four types of chemical bonds.
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POLAR COVALENT BOND
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One of two types of covalent bonds, a covalent bond in which the sharing of the electron pair is unequal, with the electrons spending more time around the more nonmetallic (electronegative) atom; in such a bond relationship there is a charge separation with one atom being slightly more positive and the other more negative; a classic example of polar covalent bonds are found in the bonds of the water molecule in which the oxygen atom is more electronegative than the hydrogens.
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IONIC BOND
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A variable strength attraction between atoms in which one or more outer shell valence electrons from one atom are removed and attached to another atom, resulting in positive and negative ions which attract each other; chemical energy is required to achieve this transfer and energy will be released if it is reversed; it is the second strongest of the four types of chemical bonds
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IONS = ELECTROLYTES
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A substance which carries an electrochemical charge because its structure has unequal numbers of electrons and protons.
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CATION
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An ion or group of ions having a positive charge and, characteristically, attracting and having the potential to make ionic bonds with negatively charged anions; such positively charged ions move toward the negative electrode in electrolysis and electrophoresis
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ANION
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An ion or group of ions having a negative charge and, characteristically, attracting and having the potential to make ionic bonds with positively charged cations; such negatively charged ions move toward the positive electrode in electrolysis and electrophoresis
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HYDROGEN BOND
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A weak (only ~5% of the strength of a covalent bond) electrostatic attraction (positive to negative) between atoms in which a hydrogen atom of one polar molecule (most often a water molecule) is attracted to an electronegative atom, especially a nitrogen, oxygen, or fluorine atom, usually of another* polar molecule of the same or a different polar substance. [*Note: Large molecules may have hydrogen bonds between atoms within the same molecule.]
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MACROMOLECULE
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Any very large molecule (more than one hundred atoms bound together at a minimum), e.g., a polymer, consisting of many smaller structural units linked together. [Examples include carbohydrates, proteins, nucleic acids, but few lipids.]
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MONOMER
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The relatively small molecular subunit which join (form covalent bonds) with similar units to form a polymer.
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POLYMER
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Any of the numerous natural and synthetic compounds, usually of high molecular weight, which consist of up to millions of repeated, covalently linked units; each subunit (monomer) is a relatively small, simple molecule.
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CARBOHYDRATE=POLYSACCHARIDE
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One of the groups of biologically important organic polymers which includes starches, celluloses, chitin and gums; they are constructed from simple sugars = monosaccharides as subunits; they contain primarily carbon, hydrogen, and oxygen, usually in the ratio 1:2:1 [represented by the shorthand formula: (CH2O)N]; some function as storage forms for nutritional energy, others function as structural components of cells and tissues.
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SUGAR-MONOSACCHARIDE
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Any of several carbohydrate subunits (monomers), such as trioses (3 carbons), tetroses (4 carbons), pentoses (5 carbons), and hexoses (6 carbons), which cannot be broken down to simpler sugars by hydrolysis; most are sweet tasting; all are crystalline, water soluble, and can be catabolized to produce useful chemical energy by oxidation and fermentation reactions. aka - simple sugar.
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GLUCOSE
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A crystalline monosaccharide, a hexose sugar, C6H12O6, occurring widely in most plant and animal tissues; it is the principal circulating sugar in the blood and the major physiological energy source of the body; its blood levels are regulated by insulin, glucagon, and certain other hormones; it is the monomer for starch, glycogen and cellulose synthesis. aka - dextrose in the food industry.
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SUCROSE
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A crystalline disaccharide of fructose and glucose, C12H22O11, found in many plants but extracted as ordinary ("table") sugar mainly from sugar cane and sugar beets' it is widely used as a sweetener or preservative and in the manufacture of plastics and soaps; it is perceived to be the most sweet tasting of the common mono- and disaccharides found in foods.
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LACTOSE
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A crystalline disaccharide of glucose and galactose, C12H22O11, found in milk; it has a slightly sweet taste and is much less soluble in water than either sucrose or glucose. aka - milk sugar.
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RIBOSE
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A crystalline monosaccharide, a pentose sugar, C5H10O5, occurring as a component of the vitamin riboflavin, and a monomer of nucleotides and ribonucleic acids (RNA).
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DEOXYRIBOSE
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A crystalline monosaccharide, a pentose sugar, C5H10O4 (containing one less oxygen than ribose), occurring as a monomer of nucleotides and deoxyribonucleic acids (DNA).
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STARCH
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A branching carbohydrate polymer [represented by the shorthand formula: (CH2O)N] composed of many repeating units of glucose, C6H12O6; this polymer of glucose serves to store energy in plants and is a major dietary nutrient for the human body; it is digested by salivary and pancreatic amylases in the digestive system.
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GLYCOGEN
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A branching carbohydrate polymer [represented by the shorthand formula: (CH2O)N] composed of many repeating units of glucose, C6H12O6; this water-soluble compound serves to store glucose in the liver and muscle tissue and elsewhere as a nutrient for future use by the body; its metabolism in the body is regulated by hormones, insulin and glucagon in particular, and also by other insulin antagonists.
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CELLULOSE
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An unbranching carbohydrate polymer composed of many repeating units of glucose ((C6H10O56)N) which are linked in a different configuration than in starch; this strong insoluble compound serves as the main structural component of the cell wall in most plants, and is important in the manufacture ofnumerous products, such as paper, textiles, pharmaceuticals, and explosives; it cannot be digested by animals but serves as "roughage" = dietary fiber which contributes to the proper flow of digested foods through the intestines.
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LIPID
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Any of a heterogeneous group of organic compounds, formed primarily from carbon and hydrogen with relatively few oxygens, all linked by nonpolar covalent bonds; examples include the fats, oils, waxes, sterols, triglycerides, cholesterol, cerebrosides, and phospholipids; these compounds are insoluble in water but soluble in nonpolar organic solvents; they are oily or waxy to the touch; certain of them are important biological signal molecules, e.g., steroid hormones and prostaglandin and leukotriene local hormones; together with carbohydrates are the major energy storage compounds in the body; and, together with carbohydrates and proteins, constitute the principal structural material of living cells.
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AMPHIPATHIC
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An adjective describing any molecule which has both hydrophobic and hydrophilic regions; it applies to both large and small molecules, such as the proteins and lipids, respectively, which are found within cell membranes; most soaps, detergents and surfactants are also amphipathic.
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HYDROPHILIC
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- Any molecules with polar covalent bonds giving the molecules an affinity for water; so that they are readily absorbed or dissolved in water.
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HYDROPHOBIC
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Any molecules with few or no polar covalent bonds giving the molecules an little affinity for water; so that they are poorly or not at all absorbed or dissolved in water; such compounds do dissolve in non-polar (lipid) organic solvents such as alcohols, ethers, etc.
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LIPOPROTEINS
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Any of the series of soluble lipid-protein complexes which are transported in the blood; each aggregate particle consists of a spherical hydrophobic core containing triglycerides and cholesterol esters surrounded by an amphipathic monolayer of phospholipids, cholesterol and apolipoproteins; classes of lipoproteins include chylomicrons, very low-density lipoproteins (VLDL), intermediate-density lipoproteins (IDL), low-density lipoproteins (LDL), and high-density lipoproteins (HDL).
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TRIGLYCERIDE
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A common biological lipid, occurring as the ester of three fatty acids and glycerol, which is the chief constituent of natural fats and oils; this group of lipids is an important energy source forming much of the fat stored by the body; elevated blood levels are correlated with the development of cardiovascular disease. aka - neutral fats.
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STERIOD
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The general term for lipids derived from cholesterol including a variety of hormones: sex hormones = gonadocorticoids (estrogens, progesterone, androgens); glucocorticoids (cortisol, cortisone, hydrocortisone, etc.) which regulate glucose metabolism and have anti-inflammatory effects; and mineralocorticoids (aldosterone) which regulate plasma water and electrolyte levels.
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CHOLESTEROL
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multiple (4-membered) carbon-ring lipid molecule which serves as a minor structural component in cell membranes and is also the precursor for synthesis of estrogen, testosterone, and related steroid hormones; elevated blood levels are correlated with the development of cardiovascular disease.
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PHOSPHOLIPID
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Any of the amphipathic molecules found in cellular membranes which consist of a glycerol residue, two non-polar fatty acid side chains and a third polar side chain which contains a phosphate ion among other polar molecular components.
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PROTEIN
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Any of a group of complex organic macromolecules which contain carbon, hydrogen, oxygen, nitrogen, and usually sulfur; they are polymers composed of one or more chains of amino acids linked covalently by peptide bonds; their three dimensional structure is complex and categorized into four structural levels, primary, secondary, tertiary, and quaternary; they are fundamental components of all living cells and include many functional types, such as structural fibers, membrane transporters, enzymes, hormones and other signal compounds, and antibodies and other immune compounds, which are necessary for the proper functioning of an organism; they are essential in the diet for the growth and repair of tissue and can be obtained from foods such as meat, fish, eggs, milk, and legumes.
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AMINO ACIDS
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Any organic compound containing an amino group (NH2), a carboxylic acid group (COOH), and any of various side groups ("R groups"); especially any of the 20 compounds that have the basic formula NH2CHRCOOH, and that link together by peptide bonds to form proteins or that function as chemical messengers and as intermediates in metabolism.
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PEPTIDE BONDS
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The characteristic covalent chemical bonds formed by dehydration synthesis between the carboxyl groups and amino groups of neighboring amino acids, establishing the initial linear linkages of the polypeptide chain, and representing the primary level of structural arrangement in the hierarchy of all protein structures.
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POLYPEPTIDE BONDS
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Molecules consisting of ~10 or more amino acids linked together by peptide bonds and exhibiting the primary, secondary, and tertiary levels of protein structure (polypeptides may be linked/bonded to form larger proteins with quaternary structure); the term is often used as if equivalent with the term protein.
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PRIMARY STRUCTURE
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In the hierarchy of protein structure, the first level - determined by the covalent peptide bonds between adjacent amino acids which produces the linear polypeptide chain.
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SECONDARY STRUCTURE
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In the hierarchy of protein structure, the second level, which is determined by the (usually hydrogen) bonds between adjacent or nearby amino acids; examples are the α-helix, β-pleated sheet, and random coil.
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TERTIARY STRUCTURE
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The bonding relationships between distant amino acids which determine the larger three-dimensional bending and folding of the protein into its complex functional shape; the third level in the hierarchy of protein structure.
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QUATERNARY STRUCTURE
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In the hierarchy of protein structure, the fourth level - determined by the bonds, either covalent or non-covalent, between amino acids on different polypeptide chains; only those proteins whose functional whole is composed of two or more polypeptide chains exhibit quaternary structure.
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ENZYME
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Complex proteins which are produced by cells and act as organic catalysts in specific biochemical/metabolic reactions
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CATALYST
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Any substance, usually used in small amounts relative to the reactants, which modifies and usually increases the rate of a reaction without being consumed in the process and, ads a result, enables a chemical reaction to proceed under different conditions (as at a lower temperature) than otherwise possible.
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NUCLEIC ACID
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Any of a group of complex organic polymers/macromolecules found in all living cells and viruses, composed of nitrogenous bases ( the purines, adenine and guanine, and the pyrimidines, cytocine, thymine, and uracil), pentose sugars (ribose and deoxy-ribose), and phosphate ions; these macromolecules, DNA and RNA, control cellular function, especially protein synthesis, and heredity.
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NUCLEOTIDE
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Any of various compounds consisting of a nitrogenous base covalently bound to a pentose sugar (a "nucleoside") and combined with one, two, or three phosphate groups/ions; they serve as the basic monomers for the synthesis of DNA and RNA; certain of them also play important roles as recyclable energy transfer compounds in a wide variety of metabolic reactions, e.g., ATP.
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NITROGENOUS BASE
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A basic compound that contains nitrogen, specifically the purines (adenine and guanine) and the pyrimidines (cytosine, thymine, and uracil) which are components of the nucleotide monomers of the nucleic acids, DNA and RNA.
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DEOXYRIBONUCLEIC ACID (DNA)
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A nucleic acid which carries the genetic information in the cell and is capable of self-replication and serves as the template for the synthesis of RNA; it is located in the nucleus and in the mitochondria of cells; it consists of two long chains of nucleotides linked by the repeated sugar-phosphate bonds, twisted into a double helix in which the two single strands are joined by hydrogen bonds between the complementary bases adenine and thymine or cytosine and guanine (A=T and C≡G); the sequence of coding triplets of nucleotides determines individual hereditary characteristics, especially the primary structure of all proteins
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DOUBLE HELIX
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The coiled three dimensional configuration of double-stranded DNA molecule in which the two strands are linked by the series of hydrogen bonds between opposing complementary nitrogenous base pairs (A=T and C≡G); so linked the two sugar-phosphate backbones form a spiral configuration around a common axis, with the two strands oriented in opposite directions ("anti-parallel").
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RIBONUCLEIC ACID (RNA)
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A group of three functional classes of nucleic acids (messenger RNA, transfer RNA, and ribosomal RNA) which participate in protein synthesis under the direction of the genetic information (DNA) in the cell; they are synthesized in the nucleus and migrate to the cytoplasm or to various cell organelles, especially the ribosomes, to carry out their functions; they consists of single long chains of nucleotides linked by the repeated sugar-phosphate bonds, twisted into various configurations, depending on their class and function; the nitrogenous bases found in RNA are adenine, guanine, cytosine and uracil.
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ATP ADENOSINE TRI-PHOSPHATE
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A nucleotide [C10H16N5O13P3] which contains the purine adenine, a pentose sugar (ribose or deoxyribose) and three high-energy phosphate groups; the potential chemical energy in the bonds connecting the phosphate groups is used to transport energy within cells for biochemical processes (including muscle contraction and enzymatic metabolism) through its hydrolysis; the mitochondrion is the primary cell organelle synthesizing this compound using energy derived from the final oxidation of nutrient molecules; it also serves as an excitatory or inhibitory neurotransmitter in the central (CNS) and peripheral (PNS) nervous systems; its release from injured cells can stimulate pain receptors.
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ANAEROBIC
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(1) a process not depending on free oxygen or air, e.g., anaerobic glycolysis; (2) living or occurring only in the absence of oxygen, e.g., anaerobic bacteria.
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AEROBIC
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(1) a process depending on free oxygen or air, e.g., aerobic glycolysis; (2) involving or improving oxygen consumption by the body, e.g., aerobic exercise; (3) living or occurring only in the presence of oxygen, e.g., aerobic bacteria.
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1. three particles which combine to form the atom.
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(positively charged) protons and (uncharged) neutrons (in the nucleus) and (negatively charged) electrons (in orbitals around the nucleus)
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2. four types of chemical bonds.
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covalent bond - ionic bond - hydrogen bond - van der Waals attraction (hydrophobic bond)
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6. two examples of major functions for carbohydrate molecules.
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1) structural components of cells and intercellular materials
(2) energy storage compounds |
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7. three examples of major functions for lipid molecules.
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(1) structural components of cellular membranes
(2) energy storage compounds (3) regulatory molecules = signal compounds |
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8. four examples of major functions for protein molecules.
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1) structural components of cytoplasm, cellular membranes and intercellular materials
(2) oxygen storage/transport compounds (3) regulatory molecules = signal compounds (4) catalysts for biochemical reactions (5) immune defensive compounds (6) membrane and plasma transport compounds |
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9. 4 levels of protein structure.
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primary - secondary - tertiary - quaternary
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10. three examples of major functions for nucleic acid molecules.
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(1) structural components of ribosomes [RNA]
(2) participants in protein synthesis (transcription and translation) [RNA] (3) the hereditary material, the location of genetic blueprints for the cell [DNA] |
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11. three chemical elements found in carbohydrates, lipids, proteins, and nucleic acids.
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carbon (C), Hydrogen (H), and oxygen (O)
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12. a chemical elements found in proteins, and nucleic acids but not in carbohydrates and lipids.
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in proteins: sulfur (S)
in nucleic acids: phosphorus (P) in both proteins and nucleic acids: nitrogen (N) |
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SUBSTRATE (ENZYME)
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The general term for a molecule which acts as a reactant in an enzyme catalyzed reaction; it is attracted to the enzyme active site and positioned to have an ideal orientation to undergo the chemical reaction being catalyzed.
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ACTIVE SITE (ENZYME)
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The portion of an enzyme, usually a depression or groove at one small part on the surface of the enzyme molecule, at which substrate(s) bind and where catalysis of the substrate(s) occurs; binding of the substrate(s) is determined by the specific three-dimensional fit between the substrate molecules(s) and the dimensions of the site as well as by compatible attractive forces such as opportunities for hydrogen or ionic bonding between substrate(s) and the site; such sites are typically very substrate specific, i.e., they accept only one or a very limited number of very similar substrate molecules; its binding and catalytic properties are determined by the specific sequence of amino acids at the site and their three-dimensional arrangement.
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ENZYME - SUBSTRATE COMPLEX
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The name given to the brief and reversible multi-molecular aggregate structure composed of the protein catalyst bound with its substrate(s); the bonding may consist of a variety of different types of bonds from the weakest hydrophobic attractions up to the temporary formation of new covalent bonds.
enzyme + substrate(s) Û enzyme-substrate(s) complex Û enzyme + product(s) |
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PRODUCT (ENZYME)
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The general term for a molecule which is formed as an output in an enzyme catalyzed reaction; it is created and released from the enzyme active site
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DENATURAION
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(1) To cause the structure of (a protein) to unfold or be rearranged, usually at the secondary, tertiary or quaternary levels, by a change in temperature, the addition of an organic solvent or a detergent, or by a change in the pH or electrolyte/salt mix in the medium, so that some of its original properties, especially its biological activity, are diminished or eliminated; the process may be reversible or irreversible. (2) To cause the paired strands of (double-stranded DNA) to separate into individual single strands, usually by the gentle application of heat; the process is usually reversible.
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