Research Rack: Glossary

adapt - to slowly evolve or change to fit the environment

adaptation - features of organisms that arise over time and enable the organisms to survive in a given environment

astrobiology - the scientific study of the living universe, its past, present, and future

astrobiologist - one who seeks to understand the origin of the building blocks of life, how compounds combine to create life, how life affects and is affected by the environment from which it came, and if and how life expands beyond its origin

atmosphere - a mass of gases surrounding a heavenly body such as a planet

biome - major division of the ecological communities on Earth characterized by the plant and animal life of that region

carbon dioxide - a colorless, odorless, incombustible gas that is formed especially by the burning and breaking down of organic substances (as in animal respiration) and that is absorbed from the air by plants in photosynthesis

climate - long-term pattern of weather that characterizes a region

consumer - a plant or animal that requires complex organic compounds for food, which it obtains by preying on other living things or eating particles of organic matter

decomposer - an organism (bacteria or fungi) that lives on and breaks down dead organisms into useful things like minerals and rich soil

ecosystem - all biotic (living) and abiotic (nonliving) things in an environment, including their interactions with each other

environment - the total circumstances surrounding an organism or group of organisms. Circumstances may include factors such as soil, climate, and other living things that influence the form and the ability of a plant, animal or ecological community to survive.

extreme environment - conditions that are far outside the boundaries in which humans live comfortably. Conditions include: pH level, air pressure, temperature, salinity, radiation, dryness (desiccation), and oxygen level.

extremophile - an organism that thrives in an extreme environment

food chain - a series of organisms in which each uses the next, usually the lower member of the series, as a food source

food web - the whole group of interacting food chains in an ecological community

gravity - force of attraction between all objects in the universe

habitat - the place where an organism naturally lives, grows, and interacts

life-form - a kind of organism

Mars - fourth planet from the Sun

meteorite - a chunk of rock from space that strikes the surface of Earth

microorganism - an animal or plant of microscopic size such as a bacterium or protozoan

nutrient - a substance that promotes growth

organism - an individual living thing that carries on the activities of life by means of organs that have separate functions but are dependent on each other: a living person, plant, or animal

pH - the chemical symbol for the scale that tells how acidic or basic a solution is

predator - an animal that lives by killing and eating other animals

prey - an animal hunted or killed by another animal for food

producer - a living thing (green plant) that makes its food from simple inorganic substances

sea level - the height of the surface of the sea midway between the average high and low tides

weather - short-term (daily) changes in temperature, wind, and/or precipitation in a region

weightlessness - lacking apparent gravitational pull