How is decomposition defined in a biological context?

Decomposition in a biological context is defined as the process by which organic matter is broken down into simpler substances through the action of microorganisms, such as bacteria and fungi, as well as physical factors like temperature and moisture. This process is crucial for nutrient cycling in ecosystems, as it transforms complex organic materials, such as dead plants and animals, into simpler inorganic substances that can be taken up by living organisms, thereby promoting soil fertility and ecosystem health.

The focus of the correct answer on the separation of compounds into similar substances emphasizes the transformative nature of decomposition as it relates to the reduction of complex organic matter into more basic elements and compounds. This breakdown is vital for the recycling of nutrients in the environment.