Pseudomonas aeruginosa is categorized as which type of microorganism?

• A. Virus
• B. Bacteria
• C. Fungus
• D. Protozoan

Answer: (B)

Classification here focuses on whether the microorganism is a prokaryotic cell or not. Pseudomonas aeruginosa is a bacterium, meaning it is a single-celled prokaryote that does not have a true nucleus or membrane-bound organelles. Bacteria have a simple cellular setup with DNA in a circular chromosome, a ribosome different from eukaryotic ones (70S), and typically a peptidoglycan-containing cell wall. They reproduce by binary fission and can thrive in many environments, including water and soil.

In contrast, viruses are acellular and require a host cell to replicate, so they’re not considered living cells. Fungi are eukaryotes with a nucleus and, in many cases, multicellular structures; their cell walls contain chitin. Protozoa are also single-celled eukaryotes with a nucleus and complex organelles.

So, Pseudomonas aeruginosa fits the bacterial category because of its prokaryotic, single-celled nature and typical bacterial characteristics.