The correct answer is: C. Cell wall
Bacteria are prokaryotes, which means they do not have a nucleus or other membrane-bound organelles. They do have a cell wall, which is a rigid structure that protects the cell and helps it maintain its shape. Plant cells also have a cell wall, but it is made of cellulose, while bacterial cell walls are made of peptidoglycan.
A. Small nucleus: Bacteria do not have a nucleus. Instead, their DNA is located in the cytoplasm, which is the fluid-filled space inside the cell.
B. Plasma membrane: All cells have a plasma membrane, which is a thin layer that surrounds the cell and separates it from the environment.
D. Spore formation: Some bacteria can form spores, which are dormant cells that can survive in harsh conditions. Spores are not unique to bacteria, however; some fungi and algae can also form spores.
In the past, bacteria were often considered to be plants because they are both prokaryotes and do not have a nucleus. However, it is now known that bacteria are more closely related to archaea than to plants. Archaea are also prokaryotes, but they have a different cell structure than bacteria. For example, archaea do not have a cell wall made of peptidoglycan.
Bacteria are an important part of the Earth’s ecosystem. They play a role in the cycling of nutrients, the decomposition of organic matter, and the production of antibiotics.