試題詳解

10. Unlike energy, matter cycles, This means that
(A) An ecosystem cannot lose chemicals from it.
(B) Ecosystems can acquire chemicals that are used up from other ecosystems.
(C) When models are built for ecosystems, all of the materials should be able to be accounted
(D) Matter is being continually converted into heat and back into matter.
(E) Chemicals contain energy, but energy doesn't contain chemicals.