How do bacteria primarily obtain their nutrients?

Bacteria primarily obtain their nutrients through absorption, decomposition, and photosynthesis. Many bacteria are absorptive heterotrophs, meaning they break down organic matter and absorb the resulting nutrients directly from their environment. This is especially true for decomposers, which play a critical role in nutrient cycling by breaking down dead organisms and organic material, thereby returning essential nutrients to the ecosystem.

In addition to absorption, some bacteria can photosynthesize, using sunlight to convert carbon dioxide and water into organic matter while releasing oxygen. This ability is characteristic of photosynthetic bacteria, such as cyanobacteria, which contribute significantly to primary production in various ecosystems.

While some bacteria do consume other organisms, the majority of their nutrient acquisition relies on absorption from their surroundings. Atmospheric gases also play a role, particularly in nitrogen-fixing bacteria that convert nitrogen gas into a usable form for plants, but this does not encompass the primary means by which most bacteria obtain nutrients. Thus, the combination of absorption, decomposition, and photosynthesis provides a more comprehensive view of how bacteria engage with their environment to acquire essential nutrients.