Bacteria are considered to be which type of organisms?

• A. Eukaryotes
• B. Fungi
• C. Viruses
• D. Prokaryotes

Answer: (D)

Bacteria are prokaryotes—organisms whose cells lack a true nucleus and other membrane-bound organelles. Their genetic material is not enclosed in a nuclear membrane; instead, DNA typically resides in a nucleoid region, and they often carry small circular chromosomes plus plasmids. The cell structure is relatively simple, with no mitochondria or chloroplasts, and their cell wall usually contains peptidoglycan. Most bacteria are unicellular, and they reproduce mainly by binary fission, a rapid, asexual division.

This distinguishes them from eukaryotes, which have a defined nucleus and membrane-bound organelles. Fungi are examples of eukaryotic organisms with complex cell structures and, in many cases, chitin in their cell walls. Viruses, on the other hand, are not cells at all; they are genetic material wrapped in a protein coat and rely on invading a host cell to replicate, so they’re not considered living cells in the same sense as bacteria.