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Biology test
biology test 1_ chapter 1
Term | Definition |
---|---|
biology | The branch of science that is concerned with the study of life and living organisms. |
atom | Smallest particle of an element that displays the properties of the element. |
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. |
Cell | The smallest unit of life that displays all the properties of life; composed of cytoplasm surrounded by a plasma membrane |
multicellular | Organism composed of many cells; usually has organized tissues, organs, and organ systems. |
tissue | Group of similar cells combined to perform a common function. |
organ | Combination of two or more different tissues performing a common function. |
organ system | Group of related organs working together; examples are the digestive and endocrine systems. |
organism | An individual; complex indivduals contain organ systems. |
population | Group of organisms of the same species occupying a certain area and sharing a common gene pool. |
community | Assemblage of species interacting with one another within the same environment. |
ecosystem | Biological community together with the associated abiotic environment; characterized by a flow of energy and a cycling of inorganic nutrients. |
biosphere | Zone of air, land, and water at the surface of the Earth in which living organisms are found. |
energy | Capacity to do work and bring about change; occurs in a variety of forms. |
metabolism | The sum of the chemical reactions that occur in a cell. |
photosynthesis | Process, usually occurring within chloroplasts, that uses solar energy to reduce carbon dioxide to carbohydrate. |
homeostasis | Maintenance of normal internal conditions in a cell or an organism by means of self-regulating mechanisms. |
reproduce | To produce a new individual of the same kind. |
development | Process of regulated growth and differentiation of cells and tissues. |
gene | Unit of heredity existing as alleles on the chromosomes; in diploid organisms, typically two alleles are inherited—one from each parent. |
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. |
mutations | Any change made in the nucleotide sequence of DNA; source of new variation for a species. |
adaptation | Species modification in structure, function, or behavior that makes a species more suitable to its environment. |
evolution | Genetic change in a species over time, resulting in the development of genetic and phenotypic differences that are the basis of natural selection; descent of organisms from a common ancestor. |
natural selection | Mechanism of evolutionary change caused by environmental selection of organisms most fit to reproduce; results in adaptation to the environment. |
taxonomy | Branch of biology concerned with identifying, describing, and naming organisms |
systematics | Study of the diversity of life for the purpose of understanding the evolutionary relationships between species. |
species | Group of similarly constructed organisms capable of interbreeding and producing fertile offspring; organisms that share a common gene pool; the taxon at the lowest level of classification. |
genus | One of the categories, or taxa, used by taxonomists to group species; contains those species that are most closely related through evolution. |
family | One of the categories, or taxa, used by taxonomists to group species; the taxon located above the genus level. |
order | One of the categories, or taxa, used by taxonomists to group species; the taxon located above the family level. |
class | One of the categories, or taxa, used by taxonomists to group species; the taxon above the order level. |
phylum | One of the categories, or taxa, used by taxonomists to group species; the taxon located above the class level. |
kingdom | One of the categories, or taxa, used by taxonomists to group species; the taxon above phylum. |
domain Bacteria | One of the three domains of life; contains prokaryotic cells that differ from archaea because they have their own unique genetic, biochemical, and physiological characteristics. |
domain Archaea | One of the three domains of life; contains prokaryotic cells that often live in extreme habitats and have unique genetic, biochemical, and physiological characteristics; its members are sometimes referred to as |
domain Eukarya | One of the three domains of life, consisting of organisms with eukaryotic cells; includes protists, fungi, plants, and animals. |
prokaryote | Organism that lacks the membrane-bound nucleus and the membranous organelles typical of eukaryotes. |
eukaryotic cell (eukaryote) | Type of cell that has a membrane-bound nucleus and membranous organelles; found in organisms within the domain Eukarya. |
Protists | The group of eukaryotic organisms that are not a plant, fungus, or animal. Protists are generally a microscopic complex single cell; they evolved before other types of eukaryotes in the history of Earth. |
plants | Multicellular, photosynthetic eukaryotes that increasingly became adapted to live on land. |
fungus (pl., fungi) | Eukaryotic saprotrophic decomposer; the body is made up of filaments called hyphae that form a mass called a mycelium. |
animals | Multicellular, heterotrophic eukaryote that undergoes development to achieve its final form. In general, animals are mobile organisms, characterized by the presence of muscular and nervous tissue. |
binomial nomenclature | Scientific name of an organism, the first part of which designates the genus and the second part of which designates the specific epithet. |
scientific method | Process by which scientists formulate a hypothesis, gather data by observation and experimentation, and come to a conclusion. |
observation | Initial step in the scientific method that often involves the recording of data from an experiment or natural event. |
inductive reasoning | Using specific observations and the process of logic and reasoning to arrive at general scientific principles. |
hypothesis | Supposition established by reasoning after consideration of available evidence; it can be tested by obtaining more data, often by experimentation. |
experiment | A test of a hypothesis that examines the influence of a single variable. Often involves both control and test groups. |
deductive reasoning | The use of general principles to predict specific outcomes. Often uses “if … then” statements. |
prediction | Step of the scientific process that follows the formulation of a hypothesis and assists in creating the experimental design. |
experimental design | Methodology by which an experiment will seek to support the hypothesis. |
experimental variable | Factor of the experiment being tested. |
responding variable | Result or change that occurs when an experimental variable is utilized in an experiment. |
control | Sample that goes through all the steps of an experiment but does not contain the variable being tested; a standard against which the results of an experiment are checked. |
model | Simulation of a process that aids conceptual understanding until the process can be studied firsthand; a hypothesis that describes how a particular process could be carried out. |
data (sing., datum) | Facts or information collected through observation and/or experimentation. |
principle | Theory that is generally accepted by an overwhelming number of scientists; also called a law. |
law | Universal principle that describes the basic functions of the natural world. |
technology | Application of scientific knowledge for a practical purpose. |
biodiversity | Total number of species, the variability of their genes, and the communities in which they live. |
extinction | Total disappearance of a species or higher group. |
climate change | Recent changes in the Earth’s climate; evidence suggests that this is primarily due to human influence, including the increased release of greenhouse gases. |
global warming | Predicted increase in the Earth’s temperature due to human activities that promote the greenhouse effect. |