Key Idea.
Section 1
The Cycle of Matter
Nature is a loop. When plants and animals die, decomposers break them down and return nutrients to the soil. New plants then use these nutrients to grow.
This is called a cycle. Matter is not destroyed; it is recycled. The atoms that made up a dead leaf yesterday might become part of a new tree tomorrow, thanks to the work of decomposers.
Section 2
Building Bodies from Food
In this cycle, every organism needs to build its body. Whether it is a decomposer eating a log, or a jaguar eating a deer, they all use food molecules to grow.
Organisms break down their food and rearrange the pieces to make their own body matter. This is how matter moves through the cycle—from plants to animals, to decomposers, and back to the soil.
Section 3
Energy Flow vs. Matter Cycle
While matter recycles, organisms also need fuel. All living things break down food molecules to release energy.
This energy powers life functions like moving, growing, and breathing. Unlike matter, which goes back into the soil, energy is used up by the organism to live. This is why organisms must act as a team to keep the ecosystem functioning.
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Section 1
The Cycle of Matter
Nature is a loop. When plants and animals die, decomposers break them down and return nutrients to the soil. New plants then use these nutrients to grow.
This is called a cycle. Matter is not destroyed; it is recycled. The atoms that made up a dead leaf yesterday might become part of a new tree tomorrow, thanks to the work of decomposers.
Section 2
Building Bodies from Food
In this cycle, every organism needs to build its body. Whether it is a decomposer eating a log, or a jaguar eating a deer, they all use food molecules to grow.
Organisms break down their food and rearrange the pieces to make their own body matter. This is how matter moves through the cycle—from plants to animals, to decomposers, and back to the soil.
Section 3
Energy Flow vs. Matter Cycle
While matter recycles, organisms also need fuel. All living things break down food molecules to release energy.
This energy powers life functions like moving, growing, and breathing. Unlike matter, which goes back into the soil, energy is used up by the organism to live. This is why organisms must act as a team to keep the ecosystem functioning.
Book overview
Jump across lessons in the current chapter without opening the full course modal.
Continue this chapter