| A | B |
|---|
| acid | A substance that increases the hydrogen ion concentration of a solution; pH <7 |
| Activation energy | The minimum amount of energy required for a chemical reaction to occur |
| Amino acid | An organic molecule that serves as the monomers of proteins. |
| Amphipathic | A molecule that has both a hydrophilic region and a hydrophobic region. |
| Anion | A negatively charged ion. |
| Atom | The smallest unit of matter that retains the properties of an element |
| ATP | adenosine triphosphate: releases free energy when its phosphate bonds are hydrolyzed. This energy is used to drive reactions in cells. |
| base | A substance that reduces the hydrogen ion concentration of a solution. (removes H+ ions or donates OH- ); pH >7 |
| Buffer | A substance that minimizes changes in pH when additional acids or bases are added to the solution. |
| Buffer system | A system that consists of acid and base forms in a solution and that minimizes changes in pH |
| Carbohydrate | A sugar (monosaccharide) or one of its dimers (disaccharides) or polymers (polysaccharides). |
| Catalyst | A chemical agent that changes the rate of a reaction without being consumed by the reaction. |
| Cation | An ion with a positive charge produced by the loss of one or more electrons. |
| Cellulose | Polysaccharide made of glucose molecules; forms cell walls in plants. |
| Chemical bond | An attraction between two atoms resulting from a sharing of outer-shell electrons or the presence of opposite charges on the atoms |
| Chemical Element | A substance that cannot be broken down to any other substance. |
| Chemical energy | Energy stored in the chemical bonds of molecules; a form of potential energy. |
| Chemical reaction | The making and breaking of chemical bonds leading to changes in the composition of matter. |
| Chemical Symbol | an abbreviation or short representation of a chemical element |
| Cofactor | Any nonprotein molecule or ion that is required for the proper functioning of an enzyme |
| compound | two or more atoms that are chemically combined |
| Concentration gradient | A region along which the density of a chemical substance increases or decreases. |
| covalent bond | when atoms share electrons allowing the outermost shells of both atoms to be filled; stronger than ionic bonds |
| Decomposition reactions (catabolism) | A metabolic pathway that releases energy by breaking down complex molecules to simpler molecules. |
| Dehydration synthesis reaction | A chemical reaction in which two molecules become covalently bonded to each other with the removal of a water molecule. |
| Denaturation | Process in which a protein loses its shape due to the disruption of weak chemical bonds and interactions thereby becoming biologically inactive. |
| diasaccharide | made of two sugar units |
| Dissociation | Breaking down of a compound into its components. |
| DNA | A double-stranded helical nucleic acid molecule capable of being replicated and determining the inherited structure of a cell's proteins. |
| Double helix | Shape of the DNA molecule |
| Electrolyte | An ionic compound that breaks apart in solution into positive and negative ions. |
| electron | negatively charged subatomic particle found in electron ring |
| Electron shell | An energy level of electrons at a characteristic average distance from the nucleus of an atom. |
| Electronegativity | The attraction of a given atom for the electrons of a covalent bond. |
| Endergonic reaction | A nonspontaneous chemical reaction in which free energy is absorbed from the surroundings. |
| Energy | The capacity to cause change especially to do work (to move matter against an opposing force). |
| Enzyme | A substance that accelerates chemical reactions in the body usually a protein |
| Exchange reactions | Chemical reaction that consists of both synthesis and decomposition reactions |
| Exergonic reaction | A spontaneous chemical reaction in which there is a net release of free energy. |
| Fatty acid | simple lipid used to synthesize triglycerides and phospholipids |
| Free radical | electrically charged atom or molecule with an unpaired electron in it's outermost shell. Highly reactive. |
| glucose | blood sugar |
| glycogen | Polymer of glucose; Functions as a store of glucose molecules in liver and muscle cells. |
| Hydrocarbon | An organic molecule consisting of carbon and hydrogen |
| hydrogen bond | A type of weak chemical bond that is formed when the slightly positive hydrogen atom of a polar covalent bond in one molecule is attracted to the slightly negative atom of a polar covalent bond in another molecule or in another region of the same molecule. |
| Hydrogen ion | A single proton with a charge of 1+ |
| Hydrolysis | A chemical reaction that breaks bonds between two molecules by the addition of water; functions in disassembly of polymers to monomers. |
| hydrophilic | water loving (polar molecule. i.e. salt) |
| hydrophobic | water fearing (non-polar molecule. i.e. oil) |
| Hydroxide ion | A water molecule that has lost a proton; OH-. |
| Inorganic compound | relatively simple compound that lacks carbon |
| ion | an atom or molecule with a charge |
| ionic bond | when one atom gives an electron (or more) to another atom. The resulting atoms become ions and are attracted to each other |
| Isomer | One of several compounds with the same molecular formula but different structures and therefore different properties. |
| isotope | atoms with different numbers of neutrons |
| Kinetic energy | The energy associated with the relative motion of objects. Moving matter can perform work by imparting motion to other matter. |
| Law of conservation of energy | Energy can be transferred and transformed but it cannot be created or destroyed. |
| Leukotrienes | Type of lipid that participates in allergic and inflammatory responses |
| lipid | Hydrophobic organic compound composed of carbon hydrogen and oxygen (do not have 2:1 ratio of hydrogen to oxygen) |
| Lipoprotein | A protein bonded to a lipid that transports fats and cholesterol in the blood |
| Macromolecule | A giant molecule formed by the joining of smaller molecules usually by a dehydration reaction. |
| Mass | Measure of the amount of matter in an object. |
| matter | has mass and volume and is recycled by decomposers |
| Mixture | Combination of elements or compounds that are physically blended together but not bound by chemical bonds |
| monomer | simple sugar monosaccharide |
| monosaccaride | C6H12O6 Examples: glucose fructose galacose |
| neutron | 0 charge subatomic particle found in nucleus |
| Nitrogenous base | Adenine thymine cytosine or guanine. |
| Non-polar covalent bond | A type of bond in which electrons are shared equally between two atoms of similar electronegativity. |
| Nucleic acid | A polymer (polynucleotide) consisting of many nucleotide monomers; DNA or RNA |
| Nucleotide | The building block of a nucleic acid consisting of a five-carbon sugar covalently bonded to a nitrogenous base and one or more phosphate groups. |
| Nucleus (of an atom) | An atom's central core containing protons and neutrons |
| Octet rule | Describes the tendency of atoms to gain or lose electrons in order to obtain eight electrons in their outer shell |
| Organic compound | Carbon containing compound held together by covalent bonds |
| Peptide bond | Bond that holds amino acids together in a protein. Formed by a deydration reaction |
| pH | describes how acidic or basic a solution is |
| Phospholipids | Amphipathic molecule that makes bilayers formin biological membranes |
| Polar covalent bond | when electrons are shared unequally one atom is partially negative while the other is partially positive. |
| polymer | carbohydrates polysaccride |
| Polysaccharide | any of a class of carbohydrates whose molecules contain chains of monosaccharide molecules |
| Potential energy | energy stored due to an object's position or arrangement |
| Primary protein structure | sequence of amino acids |
| Product | a chemical substance formed as a result of a chemical reaction |
| Properties of water | great solvent/dissolves waste products/participates in chemical reactions/absorbs and releases heat slowly/requires a lot of heat to change to gas/good lubricant/makes up most volume of cells and body fluids |
| Prostaglandins | biologically active lipids which produce many effects in the body including smooth muscle contractions inflammation and pain |
| Proteins | contains carbon hydrogen oxyge and nitrogen. source of energy. needed by tissue for repair and growth. made up of amino acids. |
| proton | positively charged subatomic particle found in the nucleus |
| Proton acceptor | A substance that takes up hydrogen ions in detectable amounts. Commonly referred to as a base. |
| Proton donor | A substance that releases hydrogen ions in detectable amounts; an acid. |
| Quaternary protein structure | made up of more than 1 strand of polypeptide Very complex (many enzymes are quaternary proteins) |
| radioactive isotopes | have unstable nuclei that break down over time emitting particles |
| Reactant | a chemical substance that is present at the start of a chemical reaction |
| Reversible reactions | chemical reactions are reversible; A + B <-----> AB |
| RNA | ribonucleic acid; a nucleic acid that plays an important role in the production of proteins |
| Salt | A compound made of minerals that in water dissolve and form electrolytes |
| Saturated fatty acid | a fatty acid whose carbon chain cannot absorb any more hydrogen atoms |
| Secondary protein structure | Alpha helices and beta sheets resulting from hydrogen bonding. |
| Solute | substance that is dissolved in a solvent to make a solution |
| Solution | A homogeneous mixture of two or more substances |
| Solvent | a liquid substance capable of dissolving other substances |
| starch | Polymer of glucose |
| steroid | Type of lipid made of four rings; Used for hormones estrogent testosterone and cholesterol |
| Subatomic particle | an electron proton or neutron; one of the three major particles of whoch atoms are composed |
| Substrate | the substance acted upon by an enzyme or ferment |
| Synthesis reactions (anabolism) | When two or more atoms ions or molecules combine to for a new larger molecule; i.e. A+B-->AB; usually requires energy |
| Tertiary protein structure | overall shape resulting from interactions between side chains of the different amino acids |
| Triglyceride | 3 fatty acids (chains of hydrocarbons) bonded to a glycerol most fats are eaten and absorbed in this form |
| Unsaturated fatty acid | a fatty acid whose carbon chain can absorb additional hydrogen atoms |
| Valence | the number of electrons in the outermost energy level of an atom |
| What are the four main elements in living things? | Hydrogen Oxygen Nitrogen Carbon |
