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vocab bio 02
Human Biology Chapter 2 Vocab.
| Question | Answer |
|---|---|
| Acid | Substances that dissociate (break up) in water, releasing hydrogen ions. |
| Adenine (A) | One of the four different type of bases in DNA. |
| ADP (adenosine diphosphate) | Usually in cells, the last phosphate bond is hydrolyzed, leaving the molecule ADP (adenosine diphosphate) and a molecule of inorganic phosphate. |
| Amino Acid | Organic molecule having an amino group and an acid group, which covalently bonds to produce peptide molecules. |
| Atom | Smallest particle of an element that displays the properties of the element. |
| Atomic Mass | Mass of an atom equal to the number of protons plus the number of neutrons with the nucleus. |
| Atomic Number | Number of protons within the nucleus of an atom. |
| ATP (adenosine triphosphate) | Nucleotide with three phosphate groups. The breakdown of ATP into ADP+ P makes energy available for energy-requiring processes in cells. |
| Base | Substances that either take up hydrogen ions (H+) or release hydroxide ions (OH-). |
| Buffer | Substance or group of substances that tend to resist pH changes of a solution, thus stabilizing its relative acidity and basicity. |
| Calorie | Amount of heat energy required to raise the temperature of 1g of water 1 Celsius. |
| Carbohydrate | Class of organic compounds that includes monosaccharides, disaccharides, and polysaccharides. |
| Cellulose | Polysaccharide that is the major complex carbohydrate in plant cell walls. |
| Complementary paired bases | Hydrogen bonding between particular bases; in DNA, thymine(T), pairs with adenine(A), and guanine(G) pairs with cytosine (C); in RNA, uracil (U) pairs with (A), and (G) pairs with (C) |
| Compound | Substances having two or more different elements united chemically in a fixed ration |
| Covalent bond | Chemical bond in which atoms share one pair of electrons. |
| Cytosine (C) | One of four nitrogen bases in nucleotides composing the structure of DNA and RNA. |
| Dehydration reaction | Chemical reaction resulting in a covalent bond with the accompanying loss of a water molecule |
| Denaturation | Loss of normal shape by an enzyme so that it no longer functions; caused by a less- than- optimal pH or temperature. |
| Disaccharide | Sugar that contains two units of monosaccharide. |
| DNA (deoxyribonucleic acid) | Nucleic acid polymer produced from covalent bonding of nucleotide monomers that contain the sugar deoxyribose; the genetic material of nearly all organisms. |
| Electron | Negative subatomic particle, moving about in an energy level around the nucleus of an atom. |
| Element | Substance that cannot be broken down into substances with different properties;composed of only one type of atom. |
| Emulsification | Breaking up of fat globules into smaller droplets by the action of bile salts or any other emulsifier. |
| Fat | Organic molecule that contains glycerol and fatty acids; found in adipose tissue. |
| Fatty acid | Molecule that contains a hydrocarbon chain and ends with an acid group. |
| Glucose | Six- Carbon sugar that organisms degrade as a source of energy during cellular respiration. |
| Glycogen | Storage Polysaccharide composed of molecules joined in a linear fashion but having numerous branches. |
| Guanine | One or four nitrogen- containing bases in nucleotides composing the structure of SNA and RNA; pairs with cytosine. |
| Hemoglobin | Iron containing pigment in red blood cells that combines with and transports oxygen. |
| Hexose | Six carbon sugar. |
| Hydrogen Bond | Weak bond that arises between a slightly positive hydrogen atom of one molecule and a slightly negative atom of another, or between parts of the same molecule |
| Hydrolysis reaction | Splitting of a compound by the addition of water, with H+ being incorporated in one fragment and the OH- in the other. |
| Hydrophilic | Type of molecule that interacts with water by dissolving in water and/or forming hydrogen bonds with water molecules. |
| Hydrophobic | Type of molecule that does not interact with water because it is nonpolar. |
| Ion | Charged particle that carries a negative or positive charge. |
| Ionic bond | Chemical bonds in which ions are attracted to one another by opposite charges. |
| Isotope | One of two or more atoms with the same atomic number but a different atomic mass due to the number of neutrons. |
| Lipid | Class of organic compounds that tends to be soluble only in nonpolar solvents such as alcohol; includes fats and oils. |
| Macromolecule | Extremely large biological molecule; refers specifically to proteins, nucleic acids, polysaccharides, lipids, and complexes of these. |
| Mass | An atom's quantity of matter. |
| Mass number | The sum of the number of protons and neutrons in the nucleus of an atom |
| Matter | Anything that takes up space and has mass. |
| Mole | A unit of scientific measurement for atoms, ions, and molecules. |
| Molecule | Union of two or more atoms of the same element; also, the smallest part of a compound that retains the properties of the compound. |
| Monosaccharide | Simple sugar; carbohydrate that cannot be decomposed by hydrolysis. |
| Neutron | Neutral subatomic particle, located in the nucleus and having a weight of approximately one atomic mass unit. |
| Nucleotide | Monomer of DNA and RNA consisting of a 5- carbon sugar bonded to a nitrogen containing base and phosphate group. |
| Nucleus | Membrane bounded organelle that contains chromosomes and controls the structure and function of a cell. |
| Oil | Substance, usually of plant origin and liquid at room temperature, formed when a glycerol molecule reacts with three fatty acid molecules. |
| Orbital | Pathways in which electrons travel around the nucleus of an atom. |
| Organic | Refers to a molecule that always contains carbon and hydrogen, and often contains oxygen as well; organic molecules are associated with living things. |
| Organic molecule | Type of molecule that contains carbon and hydrogen and often contains oxygen also. |
| Pentose | Five carbon sugar. Deoxyribose is the pentose sugar found in DNA; ribose is a pentose sugar found in RNA |
| Peptide bond | Type of covalent bond that joins to amino acids. |
| Phospholipid | Molecule that forms the bilayer of the cells membranes; has a polar, hydrophilic head bonded to two nonpolar, hydrophobic tails. |
| pH scale | Measurement scale for hydrogen ion concentration. |
| Polar | Combination of atoms in which the electrical charge is not distributed symmetrically. |
| Polypeptide | Polymer of many amino acids linked by peptide bonds. |
| Polysaccharide | Polymer made from sugar monomers; the polysaccharides starch and glycogen are polymers of glucose monomers. |
| Protein | Molecule consisting of one or more polypeptides. |
| Proton | Positive subatomic particle, locate in the nucleus and having a weight of approximately one atomic mass unit. |
| Radioisotope | Unstable form of an atom that spontaneously emits radiation in the form of radioactive particles or radiant energy. |
| RNA (ribonucleic acid) | Nucleic acid produced from covalent bonding of nucleotide monomers that contain the sugar ribose; occurs in three forms: messenger RNA, ribosomal RNA, and transfer RNA. |
| Saturated fatty acid | Fatty acid molecule that lacks double bonds between the atoms of its carbon chain. |
| Starch | Storage polysaccharide found in plants; composed of glucose molecules joined in a linear fashion with few side chains. |
| Steroid | Type of lipid molecule having a complex of four carbon rings; examples are cholesterol, progesterone, and testosterone. |
| Thymine | (T) One of four nitrogen containing bases in nucleotides composing the structure of DNA; pairs with sdenine. |
| Tracer | Substance having an attached radioisotope that allows a researcher to track its whereabouts in a biological system. |
| Trans fat | Fats, which occur naturally in meat and dairy products of ruminants, that are also industrially treated through partial hydrogenation of plant oils and animal fats. |
| Triglyceride | Neutral fat composed of glycerol and three fatty acids. |
| Unsaturated fatty acid | Fatty acid molecule that has one or more double bonds between the atoms of its carbon chain. |
| Uracil(U) | (U) The base in RNA that replaces thymine found in DNA; pairs with adenine. |