Question

which of the following best describes why decomposers are needed in an ecosystem?
a. decomposers break down large molecules of organic matter that contain nutrients for plants
b. decomposers release heat from large molecules that contain energy for animals
c. decomposers release water from large molecules that is used by plants.
d. decomposers break down large molecules of carbon dioxide into oxygen for animals

Explanation:

Decomposers, like fungi and bacteria, play a crucial role in ecosystems. They break down dead organic matter (such as dead plants and animals). Through this process of decomposition, they release nutrients (e.g., nitrogen, phosphorus) that were locked in the large organic molecules. These nutrients are then available for plants to absorb and use for growth.

• Option B: Decomposers do not release heat for animals' energy. Animals get energy from consuming food (producers or other consumers), not from heat released by decomposers.
• Option C: While water is important, the main role of decomposers is nutrient recycling (not primarily water release for plants).
• Option D: Carbon dioxide is a small molecule, and decomposers do not break down carbon dioxide into oxygen for animals. Plants produce oxygen through photosynthesis.

Answer:

A. Decomposers break down large molecules of organic matter that contain nutrients for plants