Which term describes matter that makes up the nonliving parts of an ecosystem, such as air, water, and rocks?

• A. Abiotic matter
• B. Biotic matter
• C. Ecosystem
• D. Atoms

Answer: (A)

Abiotic factors are the nonliving parts of an ecosystem, such as air, water, and rocks. The term that describes the matter making up these nonliving parts is abiotic matter. This distinguishes them from biotic matter, which is living or once-living material. An ecosystem includes both abiotic and biotic components and their interactions. Atoms are the basic building blocks of all matter, but they don’t name the category of nonliving ecosystem components; they’re simply the smallest units that compose those parts. So the term that best fits is abiotic matter.