- Adaptation: a characteristic an organism develops to aide in survival
- Bacteria: tiny living cells that "fix" nitrogen in the soil
- Biome: a region of the world that is defined by its climate and the unique plants and animals that live there
- Boiling: when heat is applied to change from liquid to a gas
- Boiling Point: the temperature at which a substance boils
- Community: all the populations of organisms living together in an environment
- Complete Metamorphosis: a four-step process including a change in an organism's body as it grows. (egg, larva, pupa, adult)
- Condensation: changing from a gas to a liquid
- Conductor: any material that allows heat or electricity to pass through it
- Consumer: an organism in a community that must eat to get the energy it needs
- Cycle: a series of events that repeats
- Decay: the slow, natural breaking down of plant and animal matter
- Decomposer: consumer that breaks down the tissues of dead organisms (bacteria, mushrooms, vulture)
- Density: the concentration of matter in an object
- Direct Development: a kind of growth where organisms keep the same body features as they grow larger
- Ecosystem: a community and its physical environment together
- Electric Circuit: any path along which electrons can flow
- Electromagnet: a magnet formed by the flow of an electric current
- Evaporation: changing from a liquid to a gas
- Fish: vertebrates that live their entire life in water
- Food Chain: the ways in which the organisms in an ecosystem interact with one another according to what they eat
- Fossil Fuel: a fuel formed from the remains of once-living organisms
- Fossils: remains of once living organisms that have been preserved
- Freezing: changing from a liquid to a solid
- Freezing/Melting Point: the temperature at which a substance transitions from a solid to a liquid
- Fungi: living things that look like plants but cannot make their own food: mushrooms
- Gas: anything that has no definite volume or shape
- Germinate: the sprouting of seeds
- Greenhouse Effect: process by which the Earth's atmosphere absorbs heat
- Habitat: a place in an ecosystem where a population lives
- Incomplete Metamorphosis: a three-step process including a change in an organism's body as it grows (egg, nymph, adult)
- Individual: a single organism
- Inherited Trait: a characteristic that is passed from parent to offspring
- Instinct: a behavior that an organism inherits
- Insulator: any material that does not allow heat or electricity to pass through
- Learned Behavior: a behavior that an animal learns from its parents
- Lens: a piece of clear material that bends light rays passing through it
- Liquid: anything that has a definite volume but no definite shape
- Mass: the amount of matter in an object
- Matter: anything that has mass and takes up space
- Melting: changing from a solid to a liquid
- Mixture: a combination of substances that can be easily separated into its own parts
- Niche: the role each population has in its habitat
- Nitrogen Cycle: the cycle in which nitrogen gas is changed into forms of nitrogen that plants can use
- Photosynthesis: the process by which plants make their own food
- Physical Properties: properties that can be observed by the senses without changing the substance
- Population: all the individuals of the same kind living in the same environment
- Producer: an organism that makes its own food (plant)
- Recycling: the process of taking a resource from a product and making it into a new item
- Reflection: light that bounces off an object
- Refraction: the bending of light rays
- Respiration: the process that releases energy; Inhale oxygen exhale carbon dioxide
- Solid: anything that has a definite volume and shape
- Solubility: the ability to dissolve
- Solution: a combination of substances that cannot be easily separated
- Symbiosis: a long-term relationship between different kinds of organisms
- System: a group of objects working together
- Variable: something that changes in an experiment and affects the results of the experiment (only 1 can be changed)
- Volume: the amount of space in an object
- Weight: the pull of gravity on an object