The matter cycle is the movement and recycling of matter through the Earth.
Matter is constantly being recycled through physical, chemical, and biological processes.
Examples of matter cycles: carbon, water, and nitrogen cycles.
Closed System
A closed system is where no matter can exit or enter the ecosystem (carbon, water, oxygen, hydrogen, and nitrogen).
Exception: Meteorites hitting the Earth.
Matter is taken up from the environment, used in life processes, and eventually returned to the Earth.
This repeating pattern is called a cycle.
The Cleanup Trio: Scavengers, Detritivores, and Decomposers
These organisms recycle matter in the ecosystem.
They eat the remains of dead plants and animals.
Roles:
Scavengers: Break down dead animals into smaller remains.
Detritivores: Break down remains into even smaller pieces.
Decomposers: Break down remains into simple substances, releasing nutrients for plants to absorb.
Decomposers and Detritivores
Decomposers: Organisms that break down dead animals, plants, and other organic matter, providing essential nutrients to the environment.
Detritivores: Animals that feed on dead organic material (detritus) and physically digest and chew it, unlike decomposers.
Ecosystems are Sustainable
Without scavengers, detritivores, and decomposers, Earth would be filled with dead organisms and byproducts.
Without new nutrients being added to the soil, plants would die, leading to the decline of other organisms, including carnivores, omnivores, and eventually humans.
Example: Nutrients
A bear catches a fish and eats most of it, leaving the carcass.
Decomposers release nutrients from the carcass.
Trees use the nutrients to grow and stay healthy.
The forest provides a home for the bear.
Carbon
Carbon is found in many places on Earth, including coal, oil, and in the air as carbon dioxide.
Carbon Cycle
Plants take in carbon dioxide from the air through photosynthesis to produce sugar.
Animals release carbon dioxide when they inhale and exhale.
Dead animals can create fossil fuels, which are burned, releasing more carbon dioxide.
Water Cycle
Evaporation: The sun's heat turns water into water vapor.
Condensation: Water vapor turns back into water droplets, forming clouds.
Precipitation: Water droplets fall back to Earth as rain, snow, hail, or sleet.
Precipitation eventually finds its way into bodies of water, and the cycle repeats.
Key Words
Cycle: A pattern in nature that repeats over time.
Sustainable: Something that can be maintained and used indefinitely.
Closed system: A system in which the amount of matter remains constant over time.
Evaporation: The process in which a substance changes state from liquid to gas.
Condensation: The change in state of a substance from gas to liquid.
Precipitation: Water in the liquid or solid state that falls to Earth.