Fungi and Parasites: The Eukaryotic Pathogens Quiz

See The Eukaryotic Targeting Problem. Human cells, fungi and protozoa share eukaryotic organisation, so E is the best answer. Eukaryotic means that the cell has a nucleus enclosed by a membrane, rather than keeping its main chromosome in an unenclosed region. Internal compartments, called organelles, allow different cellular processes to take place in different locations. This shared organisation matters when choosing drug targets: damaging a process used by both pathogen and host can harm the patient as well. Differences such as the fungal cell wall still provide useful targets, so similarity does not mean that selective treatment is impossible.

D describes the usual bacterial plan: peptidoglycan, a mesh of sugars joined by short peptides, strengthens the wall, while most bacterial membranes lack sterols. A capsid (B) is the protein coat of a virus, which is a particle rather than a eukaryotic cell. The absence of ribosomes and energy metabolism in A also fits a viral particle better than a living fungal or human cell. C places DNA in a nucleoid, an unenclosed region characteristic of bacteria; resistance-carrying plasmids are small separate DNA molecules and do not establish eukaryotic organisation.