23. Which of the following is false concerning fungal infections? Different locations of dermatophytic infections are designated Tinea corporis. Most serious human fungal infections are acquired from other people. Dimorphism (yeast mold) is observed with certain systemic fungal infections. Trichophyton, Epidermophyton, and Microsporum are dermatophytes that cause infections of the skin, nails, and hair.
24. Concerning helminths, which of the following is false? Nematodes have a body cavity and a digestive tube ending in males and females. Cestodes have no body cavity, no digestive tube, and are hermaphroditic. They are all chemoheterotrophs. Trematodes have a body cavity and a digestive tract ending in a cecum. None of the above is false.
25. Which of the following is false concerning helminths? Schistosoma mansoni requires both human and specific snail hosts. Taenia solium can acquire a mask of host antigens for disguise. Ingestion of the eggs of the beef tapeworm causes cysticercosis with systemic spread of larvae. Ascaris lumbricoides forms "worm balls" in the intestine. Liver damage with Schistosoma mansoni results from the host response (granulomas) around eggs recognized as foreign.
26. Which of the following is false concerning Streptococcus pyogenes? Gram-positive bacteria called Group A strep causes strep throat. It can cause rheumatic fever with heart damage if untreated and kidney problems (acute glomerulonephritis) if untreated.
27. Which of the following is false concerning viruses? They can have DNA or RNA, but not both, and can be single or double-stranded. Some viruses are enveloped. Some viruses have one or a few enzymes. Viruses can have icosahedral, filamentous, or complex morphology. All of the above are true of viruses.
28. Antibiotics that target cell wall synthesis ultimately cause bacterial cell death as a result of inhibition of protein synthesis, inhibition of molecular transport, decreased synthesis of plasma membrane, osmotic lysis, and cell shrinkage.