If You Were Tracking a Nutrient Molecule Through an Ecosystem

Multiple Choice

If you were tracking a nutrient molecule through an ecosystem, which of the following statements would you expect to verify?

A) Molecules move through all ecosystems at the same constant rate, as the laws of physics would predict.
B) Because of the liquid nature of the aquatic ecosystem, nutrient molecules move through it more rapidly than forest ecosystems.
C) Vertical mixing is essential for high productivity in aquatic ecosystems.
D) Most nutrient molecules leave an ecosystem, but are later replaced from another ecosystem.
E) A, B, C, and D are all correct.