The study of life.
Any genetically based phenotypic change in a population of organisms over successive generations.
A tentative, testable explanation of an observed phenomenon.
A set of disciplines that focus on various aspects of the living world.
A means of coming to understand the natural world through observation and the testing of hypotheses.
The process by which scientists investigate the natural world.
A general set of principles, supported by evidence, that explains some aspect of nature.
An element of an experiment that is changed compared to an initial condition.