Which environmental condition is conducive to the survival of bottom-dwelling microorganisms?

• A. High sulfide concentrations
• B. Low ferric iron concentrations
• C. Acidic pH levels
• D. High temperatures

Answer: (B)

The survival of bottom-dwelling microorganisms is significantly influenced by their environmental conditions. High sulfide concentrations can often be toxic to many types of microorganisms, while acidic pH levels typically limit the diversity and survival of life forms that prefer neutral to slightly alkaline conditions. High temperatures can also create environments that are inhospitable to many microorganisms, as extreme heat often affects biological processes negatively.

Low ferric iron concentrations are advantageous for bottom-dwelling microorganisms because many of these organisms can utilize the dissolved iron in their metabolic processes, particularly in environments where oxygen is limited. These microorganisms often thrive in anoxic conditions where iron is present in soluble forms, allowing them to participate in biogeochemical cycles. Therefore, low ferric iron concentrations can create favorable conditions for these microorganisms, promoting their survival and growth in habitats like ocean floors or lake beds, where they contribute significantly to nutrient cycling and the decomposition of organic materials. This ability to adapt to and thrive in such specific conditions highlights the resilience and ecological importance of bottom-dwelling microorganisms.