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Biochem
Chapter 2 & 3 Vocab
Term | Definition |
---|---|
Matter | anything that occupies space and has mass. |
Mass | the quantity of matter an object has. |
Elements | substances that cannot be broken down chemically into simpler kinds of matter. |
Atom | The simplest particle of an element that retains all of the properties of that element |
Nucleus | the central region that makes up the bulk of the mass of the mass of the atom and consists of two kinds of subatomic particles, a proton and a neutron. |
A Proton | Positively charged subatomic particle. |
Atomic number | the number of protons in an atom |
Mass number | equal to the total number of protons and neutrons of the atom |
Electrons | Small, negatively charged particles that balance the protons |
Orbital | A three-dimensional region around a nucleus that indicates the probable location of an electron |
Isotopes | Atoms that are of the same element that have a different number of neutrons |
Compounds | Something made up of atoms of two of more elements in fixed proportions |
Chemical bonds | the attractive forces that hold atoms together. |
Covalent bond | forms when two atoms share one or more pairs of electrons |
Molecule | the simplest part of a substance that retains all of the properties of that substance and can exist in a free state. |
Ion | An atom or molecule with an electric charge |
Ionic bond | The attraction between positive and negative electrical charges |
Energy | The ability to do work |
Chemical Reaction | One or more substances change to produce one or more different substances. |
Reactants | Shown on the left side of a chemical equation |
Products | Shown on the right side of a chemical equation |
Metabolism | The term used to describe all of the chemical reactions that occur in an organism |
Activation Energy | the amount of energy needed to start the reaction |
Catalysts | Chemical substances that reduce the amount of activation energy that is needed for a reaction to take place. |
Enzyme | A protein or RNA molecule that speeds up metabolic reactions without being permanently changed or destroyed |
Redox Reaction | Reaction in which electrons are transferred between atoms (oxidation-reduction reaction) |
Oxidation Reaction | Reaction in which a reactant loses one or more electrons, thus becoming positive in charge |
Reduction Reaction | Reaction in which a reactant gains one or more electrons, thus becoming negative in charge. |
Polar | When there is an uneven distribution of charge |
Hydrogen Bond | the force of attraction between a hydrogen molecule with a partial positive charge and another atom or molecule with a partial or full negative charge. |
Cohesion | An attractive force that holds molecules of a single substance together |
Adhesion | the attractive force between two particles of different substances, such as water molecules and glass molecules. |
Capillarity | the attraction between molecules that result in the rise of the surface of a liquid when in contact with a solid |
Solution | a mixture in which one or more substances are uniformly distributed in another substance. |
Solute | is a substance dissolved in the solvent |
Solvent | the substance in which the solute is dissolved |
Concentration | the amount of solute dissolved in a fixed amount of the solution |
Saturated Solution | a solution in which no more solute can dissolve |
Aqueous solution | solution in which water is the solvent- are universally important to living things |
Hydroxide Ion | OH- ion |
Hydronium Ion | H30+ ion |
Acid | any compound that increases the number of hydronium ions when dissolved in water; acid turns blue litmus paper red and reacts with bases and some metals to form salts |
Base | any compound that increases the number of hydroxide ions when dissolved in water; bases turn red litmus paper blue and react with acids to form salts |
pH scale | a range of values that are used to express the acidity or alkalinity(basicity) of a system; each whole number on the scale indicates a tenfold change in acidity; a pH of 7 is neutral, a pH of less than 7 is acidic, and a pH of greater than 7 is basic |
Buffer | A solution made from a weak acid and its conjugate base that neutralizes small amounts of acids or bases added to it |
Organic compound | a covalently bonded compound that contains carbon, excluding carbonates and oxides |
Functional groups | the portion of a molecule that is active in a chemical reaction and that determines the properties of many organic compounds |
Monomer | a simple molecule that can combine with like or unlike molecules to make a Polymer |
Polymer | a large molecule that is formed by more than 5 monomers, or small units |
Macromolecules | a very large organic molecule, usually a polymer, composed of hundreds or thousands of atoms |
Condensation reaction | a chemical reaction in which two or more molecules combine to produce water and another simple molecule |
Hydrolysis | a chemical reaction between water and another substance to form two or more new substances; a reaction between water and a salt to create an acid or a base |
Adenosine triphosphate (ATP) | an organic molecule that acts as the main energy source for cell processes; composed a nitrogenous base, a sugar, and three phosphate groups |
Carbohydrates | any organic compound that is made of carbon, hydrogen, and oxygen and that provides nutrients to the cells of living things |
Monosaccharide | a simple sugar that is the basic subunit, or monomer, of a carbohydrate |
Disaccharide | a sugar formed from two monosaccharides |
Polysaccharide | one of the carbohydrates made up of long chains of simple sugars; polysaccharides include starch, cellulose, and glycogen |
Proteins | an organic compound that is made of one or more chains of amino acids and that is a principal component of all cells |
Amino acid | an organic molecule that contains a carboxyl and an amino group and that makes up proteins; a protein monomer |
Peptide Bond | the chemical bond that forms between the carboxyl group of one amino acid and the amino group another amino acid |
Polypeptide | a long chain of several amino acids |
Substrate | a part, substance, or element that lies beneath and supports another part, substance, or element; the reactant in reactions catalyzed by enzymes |
Active site | the site of an enzyme that attaches to a substrate |
Lipids | a large, non polar organic molecule including fats and steroids; lipids store energy and make up cell membranes |
Triglyceride | a lipid made of three fatty acid molecules and one glycerol molecule |
Fatty acid | an organic acid that is contained in lipids, such as fats or oils |
Phospholipids | a lipid that contains phosphorus and that is a structural component in cell membranes |
Wax | a type of structural lipid consisting of a long fatty-acid chain that is joined to a long alcohol chain |
Steroid | a type of lipid that consists of four carbon rings to which various functional groups are attached and that usually has a physiological action |
Nucleic acid | an organic compound , either RNA or DNA, whose molecules are made up of one of two chains of nucleotides and carry genetic information |
Deoxyribonucleic acid (DNA) | the material that contains the information that determines inherited characteristics |
Ribonucleic acid (RNA) | a natural polymer that is present in all living cells and that plays a role in protein synthesis |
Nucleotide | in a nucleic-acid chain, a subunit that consists of sugar, a phosphate, and a nitrogen base |