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Glossary

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    338702
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    Glossary Entries

    Word(s)

    Definition

    Image Caption Link Source
    organic chemistry study of the chemistry of the carbon compounds        
    organic molecule Compound that contains carbon and hydrogen        
    molecular formula shows the type and number of atoms in a molecule molecular formula.png      
    structural formula  shows all atoms and the bonds attaching them lewis structure.png      
    Lewis Structure shows all atoms and electrons (bonding and nonbonding) attaching them lewis structure.png      
    Condensed structural formulas an abbreviated formula that shows all the atoms in a molecule, without showing all of the bonds condensed structure.png      
    Skeletal Structures (or line-angle structures) shows all the bonds between carbon atoms, but omits some atom labels skeletal structure.png      
    hydrocarbons Organic molecules containing only carbon and hydrogen atoms        
    alkane hydrocarbons with only C–C and C–H single bonds.        
    saturated maximum number of H atoms        
    conformers different rotational forms of a molecule conformers.png      
    Structural (or constitutional) isomers molecules with the same molecular formula but a different connectivity. structural isomers of hexane.png      
    cycloalkane Three or more carbon atoms arranged in a ring with only C-C and C-H bonds Cycloalkane.png      
    substituents groups that replace at least one H in order to branch from the alkane chain.        
    alkenes Molecules that contain a carbon-carbon double bond (C=C) and general molecular formula: CnH2n        
    parent chain longest continuous chain of carbon atoms        
    diene molecule that contains two C=C        
    polyene molecule that contains  more than two C=C        
    cycloalkene cyclic molecule that contains a C=C Cycloalkene.png      
    alkyl halide organic molecules where a halogen (F, Cl, Br, or I) has replaced a hydrogen        
    geometric (cis-trans) isomers molecues that have different arrangements because of restricted rotation around a  carbon-carbon double bond (or ring) cis-trans isomers.png      
    alkynes Molecules that contain a carbon-carbon triple bond (C≡C) and general molecular formula: CnH2n-2        
    aromatic

    class of cyclic compounds that contain a benzene ring

       

    Cacycle, Benzene Structure, CC BY-SA 3.0, via WikiMedia Commons

    functional group atoms bonded in a specific way that represents a specific class of organic compounds        
    alcohols molecules that contain the hydroxyl (–OH) functional group alcohol.png      
    primary (1o) alcohol alcohols that have one alkyl group attached to the carbon where the functional group is bonded classification of alcohols.png      
    secondary (2o) alcohol alcohols that have two alkyl groups attached to the carbon where the functional group is bonded classification of alcohols.png      
    tertiary (3o) alcohol alcohols that have three alkyl groups attached to the carbon where the functional group is bonded classification of alcohols.png      
    diol molecules that contain two hydroxyl (–OH) functional groups        
    triol molecules that contain three hydroxyl (–OH) functional groups        
    polyol molecules that contain many hydroxyl (–OH) functional groups        
    phenol molecules that contain the hydroxyl (–OH) functional group directly attached to a benzene ring phenol.png      
    thiol molecules that contain the sulfhydryl (–SH) functional group thiol.png      
    ether molecules contain the R–O–R’ functional group ether.png      
    amine Molecules derived from ammonia (NH3), where one or more hydrogen is replaced with a carbon amine.png      
    primary (1o) amine amine that has one alkyl group attached to the nitrogen of the functional group classification of amines.png      
    secondary (2o) amine amine that has two alkyl groups attached to the nitrogen of the functional group classification of amines.png      
    tertiary (3o) amine amine that has three alkyl groups attached to the nitrogen of the functional group classification of amines.png      
    carbonyl group represents a carbon-oxygen double bond (C=O)        
    aldehyde

    molecules that contain a hydrogen directly bonded to the carbon of a carbonyl group; condensed notation: R–CHO

    general structures of aldehydes.png      
    ketone molecules that contain two carbon groups directly bonded to the carbon of the carbonyl group; condensed notation: R–CO–R' general structures of ketones.png      
    carboxylic acid molecules that contain a hydroxyl (–OH) directly bonded to the carbon of a carbonyl group; condensed notation: R–COOH general structure of a carboxylic acid.png      
    esters molecules that are derivatives of carboxylic acids, formed by replacing the H of the carboxyl group with an alkyl (carbon) group; condensed notation: R–COOR' general structure of an ester.png      
    amide molecules that are derivatives of carboxylic acids, formed by replacing the OH of the carboxyl group with ammonia or an amine; condensed notation: R–CONH2' general structure of an amide.png      

    Redox (oxidation-reduction) reaction

    reactions involving a transfer of electrons        
    oxidation loss of electrons; or in organic compounds, involves an increase in oxygen and/or decrease in hydrogen         
    reduction gain of electrons; or in organic compounds, involves an decrease in oxygen and/or increase in hydrogen        
    reducing agent undergoes oxidation; responsible for something else getting reduced        
    oxidizing agent undergoes reduction; responsible for something else getting oxidized        
    addition reaction reaction in which an atom or molecule is added to an unsaturated molecule, making a single product        
    hydrogenation reaction

    addition of H2 to an alkene in the presence of a metal catalyst to produce an alkane

         
    halogenation reaction

    addition of a halogen to an alkene to produce a di-substituted alkyl halide

    halogenation reaction.png      
    hydrohalogenation reaction addition of a hydrogen halide to an alkene to produce a mono-substituted alkyl halide hydrohalogenation reaction.png      
    hydration reaction

    addition of water to an alkene in the presence of an acid catalyst to produce an alcohol

    hydration reaction.png      
    elimination reaction reaction that involves the removal of adjacent atoms from a molecule to form an alkene        
    dehydration reaction elimination reaction where water is removed from the molecule to form an alkene        
    dehydrogenation reaction elimination reaction where molecular hydrogen is removed from the molecule to form an alkene        
    dehalogenation reaction elimination reaction where a halogen is removed from the molecule to form an alkene        
    polymer large molecule formed of repeating smaller units that are covalently bonded to one another in a repeating pattern        
    monomer smaller units that make up a polymer        
    condensation reaction reaction that involves two molecules combining to form one larger organic molecule and water.        
    esterification condensation reaction that occurs when a carboxylic acid and alcohol combine to form an ester and water esterification.jpg     " Condensation Reactions" by LibreTexts is licensed under CC BY-NC .
    amidation  condensation reaction that occurs when a carboxylic acid and amine (or ammonia) combine to form an amide and water acetamide.jpg     " Condensation Reactions" by LibreTexts is licensed under CC BY-NC .
    hydrolysis reaction

    reaction that involves water reacting with an organic molecule to  break it down to form two or more smaller organic molecules; opposite of condensation

        FrozenMan, CC BY-SA 4.0, via Wikimedia Commons
    saponification alkaline hydrolysis of an ester resulting in an alcohol and fatty acid salt (ionic compound of the conjugate base)     The original uploader was Rhadamante at French Wikipedia., CC BY-SA 3.0, via Wikimedia Commons
    carbohydrates

    Sugars composed of carbon, hydrogen and oxygen that provide energy when consumed.

           
    monosaccharides simplest carbohydrates that cannot be broken down to smaller carbohydrates; general formula: Cn(H2O)n        
    disaccharides carbohydrate consisting of two monosaccharide units chemical combined through a condensation reaction         
    oligosaccharide carbohydrate consisting of 3-9 monosaccharide units chemical combined through a condensation reaction        
    polysaccharide carbohydrate consisting of 10 or more monosaccharide units chemical combined through a condensation reaction        
    chiral objects/molecules that have nonsuperimposable (not identical) mirror images        
    chiral center tetrahedral carbon bonded to four different atoms or group of atoms. chiral center.png      
    achiral objects/molecules have superimposable (identical) mirror images        
    stereoisomers molecules that have the same molecular formula and same connectivity/bonding between the atoms.         
    enantiomers stereoisomers with nonsuperimposable mirror images.     FlyScienceGuy, CC BY-SA 4.0, via Wikimedia Commons
    diastereomers stereoisomers that are not enantiomers (not exact mirror images)     FlyScienceGuy, CC BY-SA 4.0, via Wikimedia Commons
    aldose monosaccharide that contains an aldehyde group        
    ketose monosaccharide that contains a ketone group        
    sugar acid product of the oxidation of a monosaccharide         
    sugar alcohol product of the reduction  of a monosaccharide         
    pyranose six-membered ring (five carbon atoms and an oxygen) formed from aldoses pyranose and furanose (with carbon numbers).png      
    furanose five-membered ring (four carbon atoms and an oxygen) formed from ketoses pyranose and furanose (with carbon numbers).png      
    epimers diastereomers that differ only at one chiral carbon Glucose and Galactose.png      
    anomeric carbon carbon of the carbonyl group        
    anomers diastereomers that differ only at the anomeric carbon alpha and beta anomers.png      
    glycosidic bond connects two molecules to one another through a condensation reaction        
    lipid class of biomolecules defined by low solubility in water and high solubility in nonpolar, organic solvents        
    fatty acids long-chained carboxylic acids with properties similar to alkanes. fatty acid.png      
    amphipathetic contain both polar and nonpolar parts        
    monounsaturated fatty acid fatty acids that contain only one carbon–carbon double bond monounsaturated fatty acid.png      
    polyunsaturated fatty acid fatty acids that contain more than one carbon–carbon double bond fatty acid.png      
    saturated fatty acid fatty acids that contain only carbon–carbon single bonds        
    triacylglycerol (triglyceride) fats or oils; produced by the esterification of the hydroxyl groups of glycerol and the carboxyl groups of three fatty acids     Hbf878, CC0, via Wikimedia Commons
    wax lipid produced by the esterification of one fatty acid and a long-chain alcohol each containing 14 to 30 carbons        
    glycerophospholipids (or phospholipids) lipids that have a glycerol backbone with two fatty acids linked to it through an ester bond and a third group which forms a phosphoester bond with an amino alcohol.     Clbt88 at English Wikibooks, Public domain, via Wikimedia Commons
    sphingolipid phospholipids that contain an 18-carbon unsaturated amino alcohol called sphingosine, instead of glycerol.     Karol Langner at en.wikipedia, Public domain, via Wikimedia Commons
    sphingosine an amino alcohol found in all sphingolipids     Ed (Edgar181), Public domain, via Wikimedia Commons
    glycolipids 

    lipids that  contain a carbohydrate.

           
    cerebrosides glycolipids with a monosaccharide.     Epithelyann, CC BY-SA 4.0, via Wikimedia Commons
    steroids

    lipids that do not contain fatty acids; contain a steroid nucleus with four fused rings

    steroid nucleus.png      
    fat

    consist of triglycerides made up of mostly saturated fatty acids; exist as a solid or semisolid at room temperature.

           
    oil consist of triglycerides made up of mostly unsaturated fatty acids; exist as a liquid at room temperature        
    osmosis occurs when water travels across the cell membrane (from a lower to a higher solution concentration) to equalize solute concentrations inside and outside of a cell        
    isotonic solutions solute concentration inside and outside of the cell are equal        
    hypotonic solutions solute concentration outside of the cell is lower than that inside of the cell        
    hemolysis (or lysis) swelling; water flows into the cell to dilute the concentration until they are equalized        
    hypertonic solution  solute concentration outside of the cell is higher than that inside of the cell        
    crenation shrinking/shriveling; water flows out of the cell to dilute the concentration until they are equalize        
    diffusion movement of solute molecules from an area of high solute concentration to a low concentration        
    passive (or simple) diffusion small molecules and nonpolar molecules use this process to move across the semipermeable membrane; no energy required        
    semipermeable meaning that some things can enter, and some things cannot        
    facilitated transport occurs when small polar molecules and ions pass through a channel formed by integral membrane proteins; no energy required        
    active transport occurs when ions and small polar molecules move across the membrane in the opposite direction of diffusion (from low to high concentration); energy is required        
    essential amino acids must be consumed because the body cannot make them.        
    amino acids protein building blocks that contain an amino and carboxylic acid group     Benjah-bmm27, Public domain, via Wikimedia Commons
    zwitterion form of an amino acid that contains the protonated amine and carboxylat e; typically occurs at neutral pH zwitterion.png      
    protein biologically active polypeptide containing 50 or more amino acids        
    peptide compound containing amino acids joined by a peptide bond         
    denaturation process that disrupts the stabilizing attractive forces in the secondary, tertiary, and quaternary structures        
    dipeptide peptide containing only two amino acids        
    polypeptide peptide containing many amino acids        
    enzyme biological catalyst;biologically active globular proteins that accelerate chemical reactions.         
    substrate reactant in a chemical reaction (typically refers to enzyme-catalyzed reactions)        
    cofactor inorganic substances that serve as non-protein helpers        
    conenzyme organic substances , derived from vitamins, that serve as non-protein helper        
    enzyme–substrate (ES) complex interaction of the enzyme with the substrate; intermediate of an enzyme-catalyzed reaction         

    lock-and-key model

    active site that has a rigid, inflexible shape that is an exact complement to the substrate        
    induced-fit model active site that is flexible and undergoes a conformational change, adjusting to the shape of the substrate when the substrate interacts with the enzyme.        
    inhibitor Molecules that cause enzymes to lose activity by preventing the active site from interacting with substrate to form the ES complex        
    reversible inhibition

    occurs when the inhibitor causes a temporary loss of activity

           
    competitive inhibitors

    reversible inhibitors that have structures similar to that of the substrate that compete with a substrate for the active site

           
    noncompetitive inhibitors reversible inhibitors that do no have structures similar to that of the substrate and do not compete with a substrate for the active site        
    irreversible inhibition occurs when the inhibitor causes a permanent loss of activity; forms a covalent bond with an amino acid side chain in the enzyme’s active site        
    nucleic acids biomolecules composed of nucleotides        
    nucleoside sugar/base combination between a pentose and a nitrogen containing purine or pyrimidine base nucleoside.png      
    nucleotide combination between a pentose, a nitrogen containing purine or pyrimidine base, and phosphate; building blocks of nucleic acids nucleotide.png      
    transcription a segment of DNA is used to produce RNA; first step of making a protein from DNA is to make a copy of the gene from the DNA        
    messenger RNA (mRNA) codes for proteins        
    ribosomal RNA (rRNA) component of ribosomes        
    transfer RNA (tRNA) adapter molecule that brings the amino acid to the ribosome        
    replication process of making new copies of DNA         
    template strand DNA sequence that is transcribed to make RNA        
    translation process in which information in RNA is translated into a protein sequence        
    codon triplets sequence of nucleotides in mRNA;  transcribed from DNA contains a sequence of bases specifying the protein to be made     Thomas Splettstoesser  (www.scistyle.com), CC BY-SA 4.0, via Wikimedia Commons
    genetic code assigns all 20 amino acids to codons of mRNA     Sarah Greenwood, CC BY-SA 4.0, via Wikimedia Commons
    mutation change in a DNA nucleotide sequence        
    substitution (mutation) a different nucleotide is  substituted     Hullo97, CC BY-SA 4.0, via Wikimedia Commons
    insertion (mutation) a different nucleotide is  substituted     Hullo97, CC BY-SA 4.0, via Wikimedia Commons
    substitution (mutation) the addition of a new nucloetide     Hullo97, CC BY-SA 4.0, via Wikimedia Commons
    deletion (mutation) the loss/removal of a nucloetide     Hullo97, CC BY-SA 4.0, via Wikimedia Commons
    mutagen chemical or physical agents that cause mutations         
    metabolism chemical reactions occurring in the body during the break down or building up of molecules        
    metabolic pathway series of steps in the chemical reactions in biological systems        
    catabolic pathway

    chemical reactions that convert larger molecules into smaller molecules;energy is released

        CNX OpenStax, CC BY 4.0, via Wikimedia Commons
    anabolic pathway

    chemical reactions that convert smaller molecules into larrger molecules;energy is absorbed

        CNX OpenStax, CC BY 4.0, via Wikimedia Commons
    cellular respiration biochemical process in which energy is transferred from carbohydrates and fats (high potential energy molecules) to ATP         
    adenoside triphosphate (ATP) energy currency of the cell; nucleotide; undergoes hydrolysis to ADP (low energy) during which energy is released.     NEUROtiker, Public domain, via Wikimedia Commons
    digestion stage I of catabolism where food molecules are broken down by hydrolysis reactions into the individual monomer units; occurs in the mouth, stomach, and small intestine        
    glycolysis catabolic process in which glucose is converted into pyruvate via ten enzymatic steps     Thomas Shafee, CC BY-SA 4.0, via Wikimedia Commons
    aerobic conditions with oxygen        
    anaerobic without oxygen        
    citric acid cycle (or  Krebs cycle or the tricarboxylic acid cycle) series of reactions that degrade the two-carbon acetyl groups from acetyl CoA into carbon dioxide while generating the high-energy molecules NADH and FADH2.     Narayanese, WikiUserPedia, YassineMrabet, TotoBaggins, CC BY-SA 3.0, via Wikimedia Commons
    beta-oxidation (ß-oxidation) stage II of catabolism where fatty acids are converted to acetyl CoA        
    reducing sugar carbohydrate that can act as a reducing agent        
    Benedict's test qualitative test to determine whether a carbohydrate is a reducing sugar        
    pyruvate result of the breakdown of glucose during glycolysis     Pyruvic-acid-2D-skeletal.png: Benjah-bmm27derivative work: Kpengboy (talk)further derivative work GKFXtalk, Public domain, via Wikimedia Commons

     

     

    Creative Commons License
    This glossary content and images were created by Tanesha Osborne (except where noted otherwise). This work is licensed under a Creative Commons Attribution 4.0 International License (except where noted otherwise).

     

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