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What is 1 + 3?
basic unit of matter.
the center of the atom which contains the protons and neutrons; in cells, structure that contains the cell's activities.
negatively charged particle;located outside the atomic nucleus.
substance consisting entirely of one type of atom.
atom of an element that has a number of neutrons different from that of other atoms of the same element.
substance formed by the chemical combination of two or more elements in definite proportions.
bond formed when one or more electrons are transferred from one atom to another.
atom that has a positive or negative charge.
bond formed by the sharing of electrons between atoms.
smallest unit of most compounds.
van der Waals forces
a slight attraction that develops between the oppositely charged regions of nearby molecules.
attraction between molecules of the same substance.
attraction between molecules of different substances; in plants, attraction between unlike molecules.
material composed of two or more elements or compounds that are physically mixed together but not chemically combined.
mixture of two or more substances in which the molecules of the substances are evenly distributed.
substance in which a solute is dissolved to form a solution.
mixture of water and nondissovled materials.
measurement system used to indicate the concentration of hydrogen ions (H+) in solution; ranges from 0 to 14
compound that forms hydrogen ions (H+) in solution.
compound that produces hydroxide ions (OH+) in solution.
weak acid or base that cna react with strong acids or bases to help prevent sharp, sudden changes in pH.
small unit that can join together with other small units to form polymers.
large compound formed from combinations of many monomers.
compound made up of carbon, hydrogen, and oxygen atoms; major source of energy for the human body.
single sugar molecule.
large macromolecule formed from monosaccharides.
macromolecule made mainly from carbon and hydrogen atoms; includes fats, oils, and waxes.
macromolecule containing hydrogen, oxygen, nitrogen, carbon, and phosphorus.
monomer of nucleic acids made up of a 5-carbon sugar, a phosphate group, and a nitrogenous base.
ribonucleic acid (RNA)
single-stranded nucleic acid that contains the sugar ribose.
deoxyribonucleic acid (DNA)
nucleic acid that contains the sugar deoxyribose.
macromolecule that contains carbon, hydrogen, oxygen, and nitrogen; needed by the body for growth and repair and to make up enzymes.
compound with an amino group (-NH2) on one end and a carboxyl group (-COOH) on the other end.
process that changes one set of chemicals into another set of chemicals.
element or compound that enters into a chemical reaction.
element or compound produced by a chemical reaction.
energy needed to get a reaction started.
substance that speeds up the rate of a chemical reaction.
protein that acts as a biological catalyst.
reactant of an enzyme-catalyzed reaction.
substance that is dissovled in a solvent to make a sollution.