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| The simplest type of matter with unique chemical properties |
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| The smallest particle of the element that has the chemical characteristics of that element. An element is composed of atoms of only one kind. |
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| One of the 3 major types of subatomic particles with no electrical charge |
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| One of the 3 major types of subatomic particles with 1 positive charge |
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| One of the 3 major types of subatomic particles with 1 negative charge |
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| The center of an atom, composed of protons and neutrons, with electrons moving around the center |
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Definition
| The area around the nucleus, where electrons are most likely to be found |
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Term
| Atomic Number of an Element |
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Definition
| It is equal to the number of protons in the atom, and, because the number of electrons and protons is equal, the atomic number is also the number of protons in the atoms of that element. |
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| Anything that occupies space and has mass |
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| The amount of matter in an object |
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| The gravitational force acting on an object of a given mass |
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| Mass Number of an Element |
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Definition
| The number of protons plus the number of neutrons in each atom. |
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Definition
| Two or more forms of the same element that have the same number of protons and electrons but a different number of neutrons. |
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| Atomic Mass of an Element |
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Definition
| The average mass of its naturally occurring isotopes, take into account the relative abundance of each isotope. |
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Definition
| When the outermost electrons are transferred or shared, between atoms. |
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| When an atom loses or gains electrons, the number of protons and electrons are no longer equal, and a charged particle is formed |
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Definition
| When oppositely charged ions are attracted to each other, cations(+) and anions(-) tend to remain close together |
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Definition
| When atoms share one or more pairs of electrons. The resulting combinations of atoms is called a molecule. |
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| When an electron pair is shared between two atoms.It is represented with a single line between the symbols of the atoms involved. e.g. H-H |
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Definition
| When two atoms share four electrons, two from each atom.When a carbon atom combines with two oxygen atoms to form carbon dioxide, two double covalent bonds are formed. Double covalent bonds are indicated by a double line between the atoms. e.g. O=C=O |
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Definition
| When electrons are shared equally between atoms, as in a hydrogen molecule. |
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Definition
| Atoms bound to one another by a covalent bond do not always share their electrons equally, however, because the nucleus of one atom attacts the electrons more strongly than does the nucleus of the other atom. Polar covalent bonds can result in polar molecules, which are electrically asymmetric. e.g. Oxygen atoms attract electrons more strongly than do tydrogen atoms |
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Definition
| A substance composed of two or more different types of atoms that are chemically combined. Not all molecules are compounds. e.g. A hydrogen molecule is not a compund because it does not consist of different types of atoms. Some compounds are molecules and some are not.Covalent compounds in which different types of atoms are held together by covalent bonds, are molecules because the sharing of electrons results in the formation of a distinct, independent units. e.g. water |
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| Molecular Mass of a Molecule or Compound |
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Definition
| Is determined by adding up the atomic masses in atoms or (ions). It is used for convience for ioonic compounds, even though they are not compounds. |
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Definition
| When a positively charged hydrogen of one molecule is attracted to the negatively charged oxygen, nitrogen, or fluorine of another molecule |
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Definition
| When the weak electrostatic attractions between the oppositely charged parts of molecules, or between ions and molecules occur. They are much weaker than the forces producing chemical bonding. |
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Definition
| When the ability of one substance is dissolved in another. e.g. when sugar dissolves in water |
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Term
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Definition
| When ionic compounds dissolve in water, their ions separate, from one another because the cations are attracted to the negative ends of the water molecules, and the anions are attracted to the positive ends of the water molecules. e.g. When sodium chloride dissociates in water, the sodium and chloride ions separate, and water molecules surround and isolate the ions, thereby keeping them in solution. |
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Definition
| When the formula shows the kind and number of atoms present. e.g. H2 |
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Definition
| When the bonding electrons are shown as dots between the symbols of the atoms. e.g. H:H single covalent bond or O::C::O Bouble covalent bond |
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Term
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Definition
| The bonding electrons are shown as lines between the symbols of the atoms. e.g. H-H single covalent bond or O=C=O double covalen bonds |
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Definition
| Cations and anions that dissociate in water, because they have the capacity to conduct an electric current, which is the flow of charged particles. |
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Definition
| Molecules that do not dissociate form solutions that do not conduct electricity. e.g. pure water |
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Definition
| The substances that result from chemical reaction |
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Definition
| When atoms, ions, molecules or compounds interact either to form or to break chemical bonds. |
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Term
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Definition
| The substances that enter into a chemical reaction |
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Definition
| When two or more reactants chemically combine to form a new and larger product. e.g. the combination fo two amino acids to form a dipeptide. Water is formed as the amino acids are bound together. |
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Term
| Dehydration Reactions (Water Out) |
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Definition
| Synthesis reactions in which water is a product. Old chemical bonds are broken and new chemical bonds are formed as the atoms rearrange as a result of a synthesis reaction. |
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Definition
| When synthesis reactions produce the molecules characteristic of life, such as ATP, proteins, cargohydrates, lipids and nucleic acids. jAll of the synthesis reactions that occur within the body collectively as anabolism. The growth, maintenance, and repair of the body could not take place without anabolic reactions. |
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Definition
| When the reverse of synthesis reaction-a large reactant is chemically broken down in to two or more smaller products. |
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Definition
| When the breakdown of a disaccharide (a type of carbohydrate) into glucose molecules. This reaction requires water be split into two parts and that each part be contributed to one of the new glucose molecules. Reactions that use water in this manner. |
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Definition
| When the decomposition reactions that occur in the body are collectively called catabolism. e.g. the digestion of food molecules in the intestine and whin cells, the microorganisms in certain blood cells that function to protect the body. |
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Definition
| All of the anabolic and catabolic reactions in the body are collectively defined as metabolism. |
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Definition
| A chemical reaction in which the reaction can proceed from reactants to products or from product to reactants. |
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Definition
| When the rate of product formulation is equal to the rate of the reverse reaction, the reaction system is said to be at equilibrium. At equilibrium, the amount of reactants relative to the amount of product remains constant. |
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Term
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Definition
| The loss of an electron by an atom. |
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Definition
| The gain of an electron. The transfer of the electron can be complete, resulting in an ionic bond, or it can be a partial transfer, resulting in a covalent bond. |
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Term
| Oxidation-Reduction Reactions |
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Definition
When the complete or partial loss of an electron by one atom is accompanied by the gain of that electron by another atom, these reactions are called oxidation-reduction reactions.
Synthesis and decomposition reactions can be oxidation-reduction reactions. |
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Term
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Definition
| Does not occupy space and has no mass, it has the capacity to do work. |
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Definition
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Term
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Definition
| Stored energy for later. It could do work but is not doing so |
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Definition
| The form of energy that actually does work and moves matter. |
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Definition
| Energy resulting from the position or movement of object. e.g. moving a limb, breathing and circulation blood. |
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Term
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Definition
| A form of stored (potential) energy within its chemical bonds. In any chemical reaction, the potential energy contained in the chemical bonds of the reactants can be compared with the potential energy in the chemical bonds of the products. If the potential energy in the chemical bonds of the reactants is less than that of the products, then energy must be supplied for the reaction to occur. |
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Definition
| The energy that flows between objects that are at different temperatures. Heat is always transfered from the hotter object to a cooler object. |
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Definition
| The minimum energy that the reactants must have to start a chemical reaction. Even reactions that result in a release of energy must overcome the activation energy barier for the reaction to proceed. e.g. heat in the form of a spark is required to start the reaction between oxygen and gasoline vapor. |
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Term
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Definition
| Substances that increase the rate of chemical reactions without being permanently changed or depleted. |
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Term
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Definition
| Protein catalysts. Enzymes increase the rate of chemical reations by lowering the activation energy necessary for the reaction to begin. As a result, more molecules have sufficient energy to undergo chemical reactions. With an enzyme, the rate of chemical reaction can take place more than a million times faster than without the enzyme. |
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Definition
| Generally deals with those substances that do not contain carbon.These definitions have a few exceptions, e.g. carbon monoxide (CO), carbon dioxide (CO2) and bicarbonate ion (HCO3-) are classified as inorganic molecules. |
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Term
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Definition
| The study of carbon containing substances. These definitions have a few exceptions, e.g. carbon monoxide (CO), carbon dioxide (CO2) and bicarbonate ion (HCO3-) are classified as inorganic molecules. |
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Term
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Definition
| One atom of oxygen joined to two atoms of hydrogen by covalent bonds. Water molecules are polar, with a partial positive chare associated with the hydrogen atoms and a partial negative chare associated with the oxygen atom. Hydrogen bonds form between the positively chared bydrogen atoms of one water molecue and the negatively chared oxygen atoms of another water molecule. These hydrogen bond organize the water molecules into a lattice, which holds the water molecules together. Water accounts for about 50% of the weight in young adult females and 60% in young adult males |
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Definition
| When a relatively large amount of heat is required to raise its timperature; therefore, it tends to resist large temperature fluctuations. Water has a high specific heat |
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Definition
| A combination of two or more substances physically blended together, but not chemically combined. Blood is a mixture |
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Term
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Definition
| Any mixture of liquids, gases, or solids in which the substances are uniformly distributed with no clear boundary between the substances. e.g. a salt solution consists of salt dissolved in water, air is a solution containing a variety of gases, and wax is a solid solution of several fatty substances. |
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Definition
| One substance dissolving in another. The solute dissolves in the solvent. e.g. In a salt solution, water is the solvent and the dissolved salt is the solute. |
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Term
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Definition
| A mixture in which a dispersed (solute-like) substance is distributed throughout a dispersing (solventlike) substance. The dispersed particles are larger than a simple molecule but small enough that they remain dispersed and do not settle out. Proteins, which are large molecules, and water form colloids. e.g. the plasma portion of blood and the liquid interior of cells are colloids containing many important proteins. |
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Definition
| The number of particles in a solution |
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Term
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Definition
| A reflection of the number, not type, of particles in a solution |
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Definition
| A protein donor, therefore, a molecule or compound that releases hydrogen |
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Term
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Definition
| A protein acceptor, and any substance that binds to (accepts)hydrogen ions. Many bases function as proton acceptors by releasing hydroxide ions (OH-) when they dissociate |
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Term
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Definition
| A means of referring to the H+ concentration in a solution |
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Term
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Definition
| A solution with equal concentrations (PH of 7) of H+ and OH-. e.g. Pure water |
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Term
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Definition
| Solutions with a PH less than 7 and have a greater concentration of H+ than OH- |
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Term
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Definition
| Solutions that have a PH greater than 7 & have fewer H+ than OH- |
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Term
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Definition
| A compound consisting of a cation other than H+ and an anion other than a OH-. Salts are formed by the interaction of an acid and a base in which H+ of the acid are replaced by the positive ions of the base. |
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Term
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Definition
| A solution of a conjugate acid-base pair in which the acid component and the base component occur in similar concentrations. |
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Definition
| Everything that remains of an acid after the H+ (proton) is lost. |
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Term
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Definition
| Everything that remains of an acid after the H+ (proton) is lost. A conjugate acid is formed when an H+ is transferred to a conjugate base. Two substances related in this way are conjugate acid-base pair. |
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Definition
| An inorganic molecule consisting of two oxygen atoms bound together by a double covalent bond. |
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Term
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Definition
| One carbon atom bound to two oxygen atoms. Each oxygen atom is bound to the carbon atom by a double covalent bond. Carbon dioxide is produced when organic molecules, such as glucose, are metabolized whin the cells of the body. Much of the energy stored in the covalent bonds of glucose is transferred to other organic molecules when glucose is broken down, and carbon dioxide is relased. Once carbon dioxide is produced, it is eliminated from the cell as ametabolic by-product, transferred to the lungs by blood, and exhaled during respiration. |
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Definition
| Composed primarily of carbon, hydrogen and oxygen atoms & range in size frome small to very large. In most carbohydrates, for each carbon atom there are approximately two hydrogen atoms and one oxygen atom. Note that this ratio of hydrogen atoms to oxygen atoms is two to one, the same as in water. They are called carbohydrates because carbon (carbo) atoms are conbined with the same atoms that form water (hydrated). They are organic molecules, and can be broken down to provide the energy necessary for life. Undigested carbs also provide bulk in feces. |
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Term
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Definition
| Large carbohydrates that are composed of numerous, relatively simple building blocks (Mono means one & saccharide means sugar) or simple sugars. Monosacharides commonly contain 3 carbons (trioses), four carbons (tetroses), five carbons (pentoses) of 6 carbons (hexoses) |
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Term
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Definition
| The most important monosaccharides to humans include both 5 & 6 sugars, such as glucose, fructose, & galactose, which are molecules that have the same number & types of atoms but differ in their three-dimensional arrangement. |
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Term
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Definition
| Blood sugar that is the major carb found in the blood & is a major nutrient for most cells of the body |
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Term
| Components of Ribonucleic acid (RNA) |
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Definition
| 5 carbon sugars including ribose & deoxyribose |
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Term
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Definition
| Two simple sugars bound together through a dehydration reaction. |
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Term
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Definition
| Table sugar plus a molecule of water. Glucose & fructose combined together |
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Definition
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Term
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Definition
| consist of many monosaccharides bond together to form long chains that are either straight or branched |
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Definition
| animal starch- is a polysaccharide |
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Definition
| Polysarrcarides found in plants |
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Definition
| Organic molecules common to living systems. Like cars, they are composed principally of carbon, hydrogen, & oxygen, but other elements, such as phosphorus and nitrogen, are minor components of some lipids. Lipids contain a lower ratio of oxygen to carbon than do carbohydrates, which makes them less polar. Consequently, lipids can be dissolved in nonpolar organic solvents, such a alcohol or acetone, but they are relatively insoluble in water. They provide protextion & insulation & help regulate many phyusiologic processes, & form plasma membrans. In addition, lipids are a major energy-storage molecule and can be broken down and used as a source of energy. Several kinds of molecules, such as fats, phospholipids, steroids, and prostaglandins are lipids |
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Term
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Definition
| A major type of lipid that provides protection by padding & surrounding the organs & act as insulation, under the skin. Any excess chemical energy can be stored in fats |
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Term
| Triglycerides or Triacylglycerols |
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Definition
| Consist of two different building blocks: one glycerol and three fatty acids |
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Term
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Definition
| a three-carbon molecule with hydroxyl group attached to each carbon atom |
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Term
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Definition
| consisting of a straight chain of caron atoms with a carboxyl group attached at one end |
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Term
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Definition
| consiting of both an oxygen atom and a hydroxyl group attached to a caron atom. The carboxyl group is responsible for the acidic nature of the molecule because it releases hydrogen ions into solution. They can be described according to the number and kinds of fatty acids that combine with glycerol through degydration reactions |
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Term
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Definition
| Fatty acids saturated containing only single covalent bonds between the carbon atoms. e.g. eggs, cheese, pork, beef, whole milk, cocunut & palm oil |
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Term
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Definition
| One or more double covalent bonds between carbon atoms. Because the double covalent bonds can occur anywhere along the carbon chain, many types of unsaturated fatty acids with an equal degree of unsaturation are possible |
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Term
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Definition
| They have one double covalent bond between carbon atoms. e.g. olive & peanut oils |
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Term
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Definition
| They have two or more double covalent bonds between carbon atoms. They are the best type of fats in a diet, because, unlike saturated fats, they do not contribute to development of cardivascular desease. e.g. safflower, sunflower, corn, & fish oils |
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Term
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Definition
| Similar to triglycerides, except that one of the fatty acids bound to the glycerol is replaced by a molecule containg phosphate & usually nitrogen. They are polar at the end of molecule to shich the phosphate is bound and nonpolar at the other end |
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Term
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Definition
| The nonpolar end of the molecule that is attracted to water |
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Term
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Definition
| The nonpolar end of a molecule that is repelled by water |
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Definition
| A group of important chemicals derived from fatty acids. They include prostaglandins, thromboxanes & leukotrienes. Eicosanoids are made in most cells and are important regulatory molecules. They repond to tissue injuries by secreating some hormones, blood clotting some reproductive functions. |
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Definition
| A lipid that differs in chemical structure from other lipid molecules, but their solubility characteristics ar similar. All steroid molecules are composed of carbon atoms bound together into 4 ringlike structures. Important steroid molecules include cholesterol, bile salts, estrogen, progesterone, & testosterone. Cholesterol is an important steroid because other molecules are synthesized from it. e.g. bile salts, which increase fat absorption in the intestines, are derived from cholesterol, as are reproductive hormones estrogen, progesterone, and testosterone. In addition, cholesterol is an important component of plasma membranes. Although high levels of cholesterol in the blood increase the rish of cardiovascular disease, a certain amount of cholesterol is vital for normal function. |
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Definition
| Lipids with structures that are not closely related to one another, but they are nonpolar molecules essential for many normal functions of the body. |
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Definition
| All proteins contain Carbon, hydrogen, oxygen & nitrogen bound together by covalent bonds, and most proteins contain some sulfer. Inaddition, some proteins contain small amounts of phosphorus, iron, & iodine. |
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Term
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Definition
| All proteins contain Carbon, hydrogen, oxygen & nitrogen bound together by covalent bonds, and most proteins contain some sulfer. Inaddition, some proteins contain small amounts of phosphorus, iron, & iodine. They regulate bodily processes, act as a transportation system in the body, provide protection, help muscles contract, & provide structure & energy. |
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Term
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Definition
| All proteins contain Carbon, hydrogen, oxygen & nitrogen bound together by covalent bonds, and most proteins contain some sulfer. Inaddition, some proteins contain small amounts of phosphorus, iron, & iodine. |
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Term
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Definition
| A basic building block of protein. Each amino acid has a amine group(-NH2), a carboxyl group (-COOH) a hydrogen atom, and a side chain designated by the symbol R attached to the same carbon atom. The side chain can be a variety of chemical structures, and the differences in the side chains make the maino acids different from one another. |
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Term
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Definition
| Covalent bonds formed between amino acid molecules during protein synthesis. A dipeptide is two amino acids bound together by a peptide bond. A tripeptide is three amino acids bound together by peptide bonds and a polypeptide is many amino acids bound together by peptide bonds. Proteins are polypeptides composed of hundreds of amino acids. |
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Term
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Definition
| The structure of a protein that is determined by the sequence of the amino acids bound by peptide bonds. The potential number of different protein molecules is enormous because 20 different amino acids exist, and each amino acid can be located at any position along a polypeptide chain. |
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Term
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Definition
| The folding or bending of polypeptide chain caused by the hydrogen bonds between amino acids. Two common shapes that result are helices (coils) and pleated (folded) sheets. |
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Term
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Definition
| When the hydrogen bonds that maintain the shape of the protein are broken, the protein becomes nonfunctional & can be caused by abnormally high temperatures or changes in the PH of body fluids. |
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Term
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Definition
| This results from the folding of the helices or pleated sheets. Some amino acids are quite polar and therefore form hydrogen bonds whith water. The polar portions of protein tend to remain unfolded, maximizing their contact with water, whereas the less polar regions tend to fold into a globular shape, minimizing their contact with water. |
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Term
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Definition
| A folded sequence of 100-200 amino acids within a protein. The functions of proteins occur at one or more domains. Therefore, changes in the primary or secondary structure that affect the shape of the domain can change protein function. |
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Term
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Definition
| A protein catalyst that increases the rate at which a chemical reaction proceeds without the enzyme being permently changed. The three dimentional shape of anzymes is critical for their normal function because it determines the structure active site. |
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Term
| Lock and Key Model of Enzyme Action |
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Definition
| A reaction occurs when the reactants (key) bind to the active site(lock) on the enzyme. |
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Term
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Definition
| When the enzyme is able to slightly change shape and better fit the reactants. The enzyme is like a glove that does not achieve its functional shape until the hand (reactants) moves into place. |
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Term
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Definition
| Additonal nonprotein substances, required by some enzymes to be functional. A cofactor can be an ion, such as magnesium or zinc, or an organic molecule. |
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Definition
| Cofactors that are organic molecules, such as magnesium or zinc, or an organic molecules, such as certain vitamins. |
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Term
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Definition
| If two or more proteins accociate to form a functional unit, the individual proteins are called subunits. The spatial relationships between the individual subnits. |
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Term
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Definition
| An enzyme that catalyzes the breakdown of lipids. |
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Term
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Definition
| An enzyme that breaks down proteins. |
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Term
| Deoxyribonucleic Acid (DNA) |
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Definition
| The genetic material of cells, and copies of DNA are transferred from one generation fo cells to the next. DNA contains the information that determines the structure of proteins. |
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Definition
| Is structurally related to DNA, and three types of RNA also play important roles in protein synthesis. |
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Term
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Definition
| Large molecules composed of carbon, hydrogen, oxygen, nitrogen, and phosphorus. |
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Term
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Definition
| Both DNA and RNA consisting of basic building blocks. Each nucleotide is composed of a monosaccharide to which a nitrogenous organic base and phosphate group are attached. The five carbon monosaccharide is deoxyribose for DNA; it is ribaose for RNA. The nitrogenous organic bases consist of carbon and nitrogen atoms organized into rings. They are bases because the nitrogen atoms tend to take up H+ from solution. The nitrogenous organic bases are thymine, cytosine and uracil, which are single ringed pyrimidines, and adenine and guanine, which are double ringed purines. DNA has two strands of nucleotide joined together to form a twisted, ladderlike structure called a double helix. The uprights of the ladder are formed by covalent bonds between the deoxyribose molecules and phosphate groups of adjecent nucleotides. The rungs of the ladder are formed by the bases fo the nucleotides of one upright connected to the bases of the other upright by hydrogen bonds. Each nucleotide of DNA contains one of the organic bases: adenine, thymine, cytosine, or guanine. |
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Term
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Definition
| Organic bases held together by hydrogen bonds. Adenine and thymine are complementary base pairs because the structure of these organic bases allows two hydrogen bonds to form between them.Cytosine and quanine are complementary base pairs because the structure of these organic bases allows three hydrogen bonds to form between them. The two strands of DNA molecule are sid to be complementary. If the sequence of bases in one DNA strand is known, the sequence of bases in the other strand can be prediced because of complementary base pairing. |
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Term
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Definition
| When two nucleotide strands of DNA lie side by side, but their sugar phosphate "backbones" extend in opposite directions because of the orientation fo their nucleotide. A nucleotide has a 5' end and 3' end. The prime sign is used to indicate the carbon atoms of the deoxyribose sugar, which are numbered 1' to 5'. The sequence of organic bases in DNA is a "code" that stores information used to determine the structures and functions of cells. |
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Term
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Definition
| A sequence of DNA bases that directs the synthesis of proteins or RNA molecules. A gene determine the type and sequence of amino acids found in protein molecules. Because enzymes are proteins, DNA structure determines the rate and type of chemical reactions that occur in cells by controlling enzyme structure. The information contained in DNA therefore ultimately defines all ceeular activities. Other proteins, such as collagen, that are coded by DNA determine many of the structural features of humans. RNA has a structure similar to a single strand of DNA. Like DNA, four different nucleotides make up the RNA molecule, and the organic bases are the same, except that thymine is replaced with uracil. Uracil can bind only to adenine. |
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Term
| Adenosine Triphosphate (ATP) |
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Definition
An especially important organic molecule found in all living organisms. It consists of adenosine and three phosphate groups. Adenosine is th esugar ribose with the organic base adenine. The potential energy stored in the covalent bond between the second and third phosphate groups is important to living organisms because it provides the energy used in nearly all of the chemical reactions within cells. The catabolism of glucose and other nutrient molecules results in chemical reactions that release energy. Some of that energy is used to synthesize ATP from ADP and an inorganic phosphate group (Pi):
ADP + Pi + Energy (from catabolism) form ATP
The transfer of energy from nutrient molecules to ATP involves a series of oxidation-reduction reactions in which a high-energy electron is transferred from one molecule to the next molecule in the series. Once produced, ATP is used to provide energy for other chemical reactions (anabolism) or to drive cell processes, such as muscle contraction. In the process, ATP is converted back to ADP and an inorganic phosphate group. ATP is often called the energy currency of cells because it is capable of both storing and providing energy. The concentration of ATP is maintained within a narrow range of values, and eccentially all energy-requiring chemical reactions stop when there is an inadequate quanity of ATP. |
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