Archaea
One of two prokaryotic domains, the other being Bacteria.
Molecule
two or more atoms held together by covalent bonds
Climate Change
A directional change in temperature, precipitation, or other aspect of the global climate that lasts for three decades or more.
Biology
the scientific study of life
inquiry
The search for information and explanation, often focusing on specific questions.
Organ
A specialized center of body function composed of several different types of tissues.
prokaryotic cell
A type of cell lacking a membrane-enclosed nucleus and membrane-enclosed organelles; found only in the domains Bacteria and Archaea.
Evolution
Descent without modification; the process by which species accumulate differences from their ancestors as they adapt to different environments over time; also defined as a change in the genetic composition of a population from generation to generation.
Technology
The application of scientific knowledge for a specific purpose, often involving industry or commerce but also including uses in basic research.
Population
group of individuals of the same species that live in the same area and interbreed, producing fertile offspring.
Producer
An organism that produces its own compounds from CO2 by harnessing light energy (in photosynthesis) or by oxidizing inorganic chemicals (in chemosynthetic reaction carried out by some prokaryotes).
independent variable
A factor whose value is manipulated or changed during an experiment to reveal possible effects on another factor (the dependent variable).
DNA (deoxyribonucleic acid)
A nucleic acid molecule, usually a double-stranded helix, in which each polynucleotide strand consists of nucleotide monomers with a deoxyribose sugar and the nitrogenous bases adenine (A), cytosine (C), guanine (G), and thymine (T); capable of being replicated and determining the inherited structure of a cell's proteins.
Biosphere
The entire portion of Earth inhabited by life; the sum of all the planet's ecosystems.
Bioinformatics
The use of computers, software, and mathematical models to process and integrate biological information from large data sets.
Dependent variable
A factor whose value is measured during an experiment or other test to see whether it is influenced by changes in another factor (the independent variable).
Genome
The genetic material of an organism or virus; the complete complement of an organism's or virus's genes along with its noncoding nucleic acid sequences.
Model organism
A particular species chosen for research into broad biological principles because it is representative of a larger group and usually easy to grow in a lab.
genomics
the systematic study of whole sets of genes (or other DNA) and their interactions within a species, as well as genome comparisons between species
tissue
An integrated group of cells with a common function, structure, or both.
Experiment
A scientific test. Often carried out under controlled conditions that involve manipulating one factor in a system in order to see the effects of changing that factor.
gene expression
The process by which information encoded in DNA directs the synthesis of proteins or, in some cases, RNAs that are not translated into proteins and instead function as RNAs.
Inductive reasoning
A type of logic in which generalizations are based on a large number of specific observations.
Eukarya
The domain that includes all eukaryotic organisms.
controlled experiment
An experiment designed to compare an experimental group with a control group; ideally, the two groups differ only in the factor being tested.
Variable
A factor that varies in an experiment.
Bacteria
One of two prokaryotic domains, the other being Archaea.
Eukaryotic cell
A type of cell with a membrane-enclosed nucleus and membrane-enclosed organelles. Organisms with eukaryotic cells (protists, plants, fungi, and animals) are called eukaryotes
ecosystem
All the organisms in a given area as well as the abiotic factors with which they interact; one or more communities and the physical environment around them.
organelle
Any of several membrane-enclosed structures with specialized functions, suspended in the cytosol of eukaryotic cells.
Science
an approach to understanding the natural world
natural selection
A process in which individuals that have certain inherited traits tend to survive and reproduce at higher rates than other individuals because of those traits.
Community
All the organisms that inhabit a particular area; an assemblage of populations of different species living close enough together for potential interaction.
Proteomics
the systematic study of sets of proteins and their properties, including their abundance, chemical modifications, and interactions
Hypothesis
a testable explanation for a set of observations based on the available data and guided by inductive reasoning. A hypothesis is narrower in scope than a theory.
Theory
An explanation that is broader in scope than a hypothesis, generates new hypotheses, and is supported by a large body of evidence.
Deductive reasoning
A type of logic in which specific results are predicted from a general premise.
Organism
An individual living thing, consisting of one or more cells.
Cell
life's fundamental unit of structure and function; the smallest unit of organization that can perform all activities required for life.
Gene
A discrete unit of hereditary information consisting of a specific nucleotide sequence in DNA (or RNA, in some viruses).
Proteome
the entire set of proteins expressed by a given cell, tissue, or organism.
Feedback Regulation
the regulation of a process by its output or end product
Systems Biology
An approach to studying biology that aims to model the dynamic behavior of whole biological systems based on a study of the interactions among the system's parts.
Consumer
an organism that feeds on producers, other consumers, or nonliving organic material.
Emergent Properties
New properties that arise with each step upward in the hierarchy of life, owing to the arrangement and interactions of parts as complexity increases.
Data
recorded observations.