Indoor Air sciences CSMI Practice Exam

What does saprobic mean?

1. Heterotrophic organisms obtaining nutrients from non-living organic matter

2. Autotrophic organisms obtaining nutrients through photosynthesis

3. Viruses that inject DNA via a probing capsid

4. Bacteria that multiply using simple cell division

The correct answer is: Heterotrophic organisms obtaining nutrients from non-living organic matter

Saprobic refers to a specific ecological role played by certain organisms, particularly decomposers, in the decomposition of organic matter. The correct answer highlights that saprobic organisms are heterotrophic, meaning they cannot produce their own food and instead obtain nutrients from the breakdown of non-living organic matter, such as dead plants and animals, as well as decaying material. This process is vital for nutrient cycling in ecosystems, as it helps to recycle nutrients back into the environment, promoting soil health and facilitating plant growth. Understanding the saprobic process is crucial in the context of indoor air science, as it underpins the role of many microbial agents in maintaining indoor air quality. For example, mold and certain bacteria can be saprobic, breaking down organic materials and potentially impacting air quality if they proliferate indoors. The other choices provided do not accurately describe the concept of saprobic. Autotrophic organisms obtain nutrients through photosynthesis rather than decomposing organic matter. The description of viruses involves a process distinct from how saprobic organisms contribute to their environment. Lastly, bacteria multiplying through simple cell division does not directly relate to the function of being saprobic, which emphasizes nutrient acquisition from non-living sources.