As part of a research project, a graduate student creates an artificial environment in a sealed container. She sterilizes the soil and adds plants, snails, shrews, and a snake. After adding a small artificial pond, she seals the container. During the first several weeks, the plants are thriving and the animals are doing well. However, piles of dropping are beginning to accumulate, and the entire floor of the container becomes covered with a layer of plant debris several inches thick. One probable cause for the problems is that the graduate student didn't:

Question

Quizplus · Accepted Answer

The piles of droppings and layer of plant debris are indications that there is no organism present to decompose organic matter. This suggests that the graduate student did not include any decomposers in the container.

As Part of a Research Project, a Graduate Student Creates