ILEARN Science Grade 4 flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

Mass

The amount of matter in an object. Mass is measured with a balance and stays the same even if gravity changes.

Volume

The amount of space an object or substance takes up. It can be measured with a ruler for blocks or a graduated cylinder for liquids.

Solid

A state of matter that has a fixed shape and a fixed volume. Its particles are packed closely and vibrate in place.

Liquid

A state of matter with a fixed volume but no fixed shape. It flows and takes the shape of its container.

Gas

A state of matter with no fixed shape or volume. Gas particles spread out to fill whatever container holds them.

Melting

A change of state from solid to liquid caused by adding heat, such as ice becoming water at zero degrees Celsius.

Condensation

A change of state from gas to liquid caused by cooling, such as water vapor forming droplets on a cold glass.

Physical change

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

Chemical change

A change that produces a new substance with different properties, often shown by color change, bubbles, heat, or light.

Closed circuit

A complete unbroken path for electric current. It needs a power source, wires, and a device such as a bulb.

Conductor

A material that lets heat or electricity pass through easily, such as copper wire or metal spoons.

Photosynthesis

The process plants use to make food. Plants take in sunlight, water, and carbon dioxide and release oxygen.

Producer

An organism that makes its own food, usually a green plant using sunlight. Producers form the base of every food chain.

Consumer

An organism that cannot make its own food and must eat other organisms to get energy, such as animals.

Decomposer

An organism such as a fungus or bacterium that breaks down dead plants and animals and returns nutrients to the soil.

Food chain

A model showing the order in which energy passes from one organism to another, starting with a producer.

Food web

A model of several connected food chains in an ecosystem, showing many feeding relationships among organisms.

Adaptation

A body part or behavior that helps an organism survive in its habitat, such as thick fur in cold climates.

Habitat

The place where an organism lives and gets the food, water, shelter, and space it needs to survive.

Life cycle

The stages an organism passes through from birth to adult to producing offspring, such as egg, larva, pupa, adult.

Inherited trait

A characteristic passed from parents to offspring through genes, such as eye color or fur pattern.

Learned behavior

A skill an animal gains through experience or practice, such as a bird learning a song or a pet learning tricks.

Ecosystem

All the living organisms in an area plus the nonliving parts they interact with, such as soil, water, and air.

Rotation

The spin of Earth on its axis, taking about 24 hours. Rotation causes day and night.

Revolution

The orbit of Earth around the Sun, taking about 365 days. Revolution, with Earth's tilt, causes the seasons.

Moon phases

The changing shapes of the Moon's lit side seen from Earth, cycling through new, crescent, quarter, gibbous, and full.

Water cycle

The repeating movement of water through evaporation, condensation into clouds, precipitation, and collection in bodies of water.

Evaporation

The change of liquid water into water vapor, usually caused by heat from the Sun, which sends water into the air.

Weather

The condition of the air and sky in a place at a certain time, including temperature, wind, and precipitation.

Climate

The usual weather pattern of a place measured over many years, such as hot and dry or cold and snowy.

Fossil

Preserved remains or traces of an organism from long ago, found in rock and used to learn about past life.

Renewable resource

A natural resource that nature replaces in a short time, such as sunlight, wind, or flowing water.