RISE Science Grade 6 key terms

The carrying away of weathered rock, soil, and sediment by moving water, wind, or ice. It shapes landforms over time and can be sped up by loss of plant cover.

The breaking down of rock into smaller pieces where it sits, caused by water freezing, plant roots, or chemical reactions. The broken pieces may later be moved by erosion.

The dropping of eroded sediment when moving water, wind, or ice slows down. Deposited layers may pile up and, over long periods, harden into sedimentary rock.

Rock formed when layers of sediment are pressed and cemented together over long periods. It often contains fossils and shows visible layering.

The ongoing set of processes that change rock among igneous, sedimentary, and metamorphic forms through melting, cooling, weathering, and heat and pressure.

Preserved remains or traces of a once-living organism, usually found in sedimentary rock. Fossils give evidence about organisms and environments of the past.

The theory that Earth's outer shell is broken into large moving plates. Their motion causes earthquakes, volcanic activity, and the building of mountains.

A sudden shaking of the ground caused by the release of built-up energy along a fault, where rock masses slip past each other.

A place where melted rock, ash, and gases escape from inside Earth onto the surface. Most volcanoes occur near boundaries between tectonic plates.

The continuous movement of water among the ocean, atmosphere, and land through evaporation, condensation, precipitation, and collection. Energy from the Sun drives the cycle.

The change of a liquid into a gas, which happens when particles gain enough energy. In the water cycle, it moves water from oceans and lakes into the air.

The change of a gas into a liquid when particles lose energy, such as when water vapor cools and forms cloud droplets. It is a key step in the water cycle.

A natural resource that is replaced by natural processes as fast as, or faster than, people use it, such as sunlight, wind, and flowing water.

A natural resource that forms over very long periods and is used up faster than it is replaced, such as coal, oil, and natural gas.

The smallest unit of a living thing that can carry out the basic activities of life. Some organisms are a single cell; others are made of many cells.

The thin outer covering of a cell that holds the cell together and controls which materials move into and out of it.

A specialized structure inside a cell that performs a particular job, such as the nucleus storing genetic material or chloroplasts capturing light energy.

A green organelle in plant cells where photosynthesis takes place. It contains chlorophyll, which captures light energy used to make food.

The process by which plants and other producers use light energy, water, and carbon dioxide to make sugar and release oxygen. It is the main source of energy for most food chains.

A model showing the order in which energy passes from one organism to another, beginning with a producer and ending with a consumer at the top.

An organism that makes its own food using energy from sunlight or chemicals, usually through photosynthesis. Producers form the base of food chains and food webs.

An organism that gets its energy by eating other organisms rather than making its own food. Consumers may eat producers or other consumers.

An organism such as a fungus or bacterium that breaks down dead organisms and waste, releasing nutrients back into the soil and ecosystem.

All the living organisms in an area together with the nonliving parts of their environment, such as water, soil, air, and sunlight, interacting as a system.

A feature or behavior of an organism that helps it survive and reproduce in its environment, such as thick fur in cold climates or camouflage.

The process by which organisms with traits that suit their environment tend to survive and reproduce more, so those helpful traits become more common over generations.

Anything that has mass and takes up space. Matter is made of particles and can exist as a solid, liquid, or gas.

The amount of matter in an object, measured in grams or kilograms. Mass stays the same when an object changes location or shape.

The amount of space an object or substance takes up, often measured in liters or cubic centimeters. It can be found by measuring displaced water.

How much mass is packed into a given volume of a substance, often found by dividing mass by volume. Denser objects sink in less dense fluids.

The forms matter can take: solid, liquid, and gas. The state depends on how the particles are arranged and how much energy they have.

A change in a substance's appearance, shape, or state that does not create a new substance, such as melting ice or tearing paper.

A change in which one or more new substances form with different properties from the originals, such as rusting, burning, or baking batter.

A push or pull on an object that can change its motion or shape. Force has both a size and a direction and is measured in newtons.

A force that resists motion when two surfaces rub against each other. It converts some motion energy into heat and can slow objects down.

A force of attraction between objects that have mass. Earth's gravity pulls objects toward its center and keeps the Moon in orbit.

The ability to cause change or do work. Energy exists in forms such as motion, light, sound, heat, and chemical energy and can move between objects and forms.

The energy an object has because it is moving. It increases when the object's mass or speed increases.

Stored energy an object has because of its position or condition, such as a ball held high above the ground or energy stored in food.

The curved path one object follows as it moves around another because of gravity, such as Earth's yearly path around the Sun.

A testable prediction or possible explanation that can be checked with an investigation. It is stated before data are collected and may be supported or revised.

A factor in an investigation that can change. A fair test changes only one variable at a time while keeping the others the same.

Information gathered through observation or measurement that is used to support or challenge a claim. Strong evidence is repeatable and comes from careful procedures.