* animal Multicelled consumer with unwalled cells; develops through a series of stages and moves about during part or all of the life cycle. * archaean Member of a group of single-celled microorganisms that superficially resemble bacteria, but are genetically and structurally distinct. * atom Particle that is a fundamental building block of all matter. * bacterium Single-celled organism belonging to the Domain Bacteria; cells are typically walled and do not contain a nucleus. * biodiversity Of a region, the genetic variation within its species, variety of species, and variety of ecosystems. * biology The scientific study of life.
* biosphere All regions of Earth where organisms live. * cell Smallest unit that has the properties of life; at minimum, consists of plasma membrane, cytoplasm, and DNA. * community All populations of all species that live a particular region. * consumer Organism that gets energy and nutrients by feeding on tissues, wastes, or remains of other organisms; a heterotroph. * control group In an experiment, group of individuals who are not exposed to the independent variable that is being tested. * critical thinking Judging the quality of information before allowing it to guide one's thoughts or actions. * data Experimental results.
* deductive reasoning Using a general idea to make a conclusion about a specific case. * dependent variable In an experiment, variable that is presumably affected by the independent variable being tested. * development Multistep process by which the first cell of a new individual becomes a multicelled adult. * DNA Deoxyribonucleic acid. Nucleic acid that carries hereditary information about traits; consists of two nucleotide chains twisted in a double helix. * ecosystem A community interacting with its environment. * emergent property A characteristic of a system that does not appear in any of the system's component parts. * energy The capacity to do work.
* eukaryote Organism whose cells characteristically have a nucleus. * experiment A test designed to support or falsify a prediction. * experimental group In an experiment, group of individuals who are exposed to an independent variable. * fungus Eukaryotic heterotroph with cell walls of chitin; obtains nutrients by digesting food outside the body and absorbing them. * genus A group of species that share a unique set of traits; also the first part of a species name. * growth In multicelled species, an increase in the number, size, and volume of cells. * homeostasis Set of processes by which an organism keeps its internal conditions within tolerable ranges. * hypothesis Testable explanation of a natural phenomenon. * independent variable Variable that is controlled by an experimenter in order to explore its relationship to a dependent variable. * inductive reasoning Drawing a conclusion based on observation. * inheritance Transmission of DNA from parents to offspring. * law of nature Generalization that describes a consistent natural phenomenon for which there is incomplete scientific explanation. * model Analogous system used for testing hypotheses. * molecule Two or more atoms joined by chemical bonds. * nucleus Of an atom, the core region occupied by protons and neutrons. Of a eukaryotic cell, an organelle with two membranes that holds the cell's DNA. * nutrient Substance that an organism needs for growth and survival, but cannot make for itself. * organ In multicelled organisms, a grouping of tissues engaged in a collective task. * organ system In multicelled organisms, set of organs engaged in a collective task that keeps the body functioning properly. * organism Individual that consists of one or more cells. *...