Figure 1.

Basic structure of bacteria and their associated environmental reservoirs. Bacteria possess a simple body structure without a true nucleus or membrane-bound organelles. Their basic structure comprises the cell wall, which offers structural support and protection, and the plasma membrane, which surrounds the cytoplasm and distinguishes it from the external environment. In addition, some bacteria possess a protective outer layer known as the capsule, which aids them in evading the host's immune system. Bacteria are commonly found in various environments, such as animals, food, humans, air, water, soil, and plants.