251 - 300 Micro Para

251. Viruses can be cultivated in the following media, EXCEPT: A. Monkey kidney cells B. Embryonated eggs C. Human amniotic fluid D. Enriched agar medium with human serum 252. Nonsporing anaerobic bacteria do NOT cause: A. Lung abscess B. Peritonitis C. Interstitial pneumonia D. Gas gangrene

253. Demonstration of the undisturbed relationship between fungal spores and hyphae is BEST done by: A. Gram’s stain B. KOH wet mount C. India ink wet mount D. Lactophenol cotton blue ink wet mount

254. Most antibodies are synthesized by the: A. Central lymphoid organs B. Peripheral lymphoid organs C. Primary lymphoid organs D. Macrophages 255. In which of the following parasitic human infections occurs by ingestion of encysted embryos in porcine flesh? A. Hymenolepis nana B. Trichinella spiralis C. Echinococcus granulosus D. Trichuris trichiura 256. The size of viruses is measured by: A. Filtration B. Ultracentrifugation C. Electron microscopy D. All of the above 257. Anaerobes are MOST susceptible to: A. Cephalosporins B. Sulfas C. Metronidazole D. Macrolides 258. A mycosis may co-exist with another disease particularly a: A. Skin infection B. GIT disturbance

C. Typhoid fever D. Lymphomatous disease 259. The production of antibodies requires the proliferation & differentiation of: A. B lymphocytes B. Effector T cells C. Suppressor T cells D. Cytotoxic T cells 260. Which of the following is a correct statement regarding the intermediate host? A. It harbors the adult stage of the parasite B. It is where the parasite reproduces sexually C. In most parasitic infections, man usually acts as the intermediate host D. It harbors the larval stage of the parasite 261. What is the BEST temperature for the transport of specimen of patients to the laboratory for viral culture? A. 37° C B. 42° C C. 25° C D. 4° C 262. The MOST common anaerobic infection is caused by: A. Actinomyces B. Bacteroides C. Fusobacterium D. Clostridium 263. Lymphoma patients will MOST likely be predisposed to: A. Candidiasis B. Aspergillosis C. Mucomycoses D. All of the above 264. Immunoglobulin molecules contain all of the following, EXCEPT: A. Heavy chains B. Phagosomes C. Domains D. Hinge regions 265. In which of the following parasitic infections will man act as an intermediate host? A. Dracontiasis B. Taeniasis C. Hydatid cystic disease D. Filariasis

266. Which of the following is a mammalian cell product that can render a cell refractory to infection by a virus? A. Interferon B. Adenosine arabinoside C. Ara-C D. All of the above 267. Which of the following is NOT anaerobic? A. Fusobacterium B. Bacteroides C. Branhamella D. Clostridium 268. Systemic mycosis is commonly acquired by: A. Oral route B. Parenteral route C. Inhalation of spores D. Skin contact 269. During the maturation of a B lymphocyte, the first immunoglobulin heavy chain synthesized is the: A. mu chain B. gamma chain C. epsilon chain D. alpha chain 270. Which of the following parasitic infections is transmitted to man by ingestion of improperly cooked beef? A. Hymenolepis nana B. Taenia saginata C. Echinococcus granulosus D. Clonorchis sinensis 271. Interferon acts against acute viral infection by: A. Destroying viruses in infected cells B. Stimulating a highly specific response in lymphocytes C. Inducing resistance in uninfected cells D. All of the above 272. Bacteria that are able to grow at temperature below 25°C are called: A. Halophiles B. Psychrophiles C. Osmophiles D. Thermophiles

273. The most prevalent type of dermatomycosis in man known as “athlete’s foot” is usually caused by: A. Trichophyton sp B. Microsporum gypseum C. Candida albicans D. Microsporon sp 274. Injection of antigen into the skin of a sensitive individual can lead to: A. Development of wheal & erythema B. Shock C. Vascular engorgement D. Asphyxia from bronchoconstriction 275. Which of the following parasitic infections is transmitted to man through cats? A. Isospora hominis B. Toxoplasma gondii C. Chilomastix mesnili D. Trichomonas hominis 276. Which of the following BEST describes the mode of resistance conferred by interferon? A. It stimulates cell-mediated immunity B. It stimulates humoral immunity C. Its action is related to the synthesis of protein that inhibits translation or transcription D. It alters the permeability of the cell membrane so that viruses cannot enter the cell 277. Bacteria that are able to grow at temperatures as high as 50°C to 55°C are called: A. Halophiles B. Psychrophiles C. Osmophiles D. Thermophiles 278. Sputum examination can be of diagnostic help in which of the following parasitic infections? A. Paragonimiasis B. Amebic liver abscess C. Diphyllobothriasis D. Taeniasis 279. Which of the following parasitic infections is transmitted to man by ingestion of water plants? A. Fasciola hepatica B. Chlonorchis sinensis C. Diphyllobothrium latum D. Necator americanus 280. Which of the following statements is NOT true regarding host-defense against viral infection? A. Interferon can protect uninfected cells by inhibiting viral replication within cells B. Interleukin-2 can protect uninfected cells by inhibiting the release of virus from the cell C. Serum IgG can prevent viral infection by inhibiting viral entry into cells D. Secretory IgA can prevent viral infection of the mucosal cells of the pharynx

281. Which of the following diseases is NOT preventable by vaccination? A. Measles B. Variola C. Varicella D. Poliomyelitis 282. L forms are correctly described as: A. Generally susceptible to amphotericin B B. Unable to revert to their bacterial parental types C. Not induced by penicillin or UV light D. Containing sterols in their membrane 283. The MOST common nosocomial fungal superinfection is caused by: A. Histoplasma B. Nocardia C. Candida D. Cryptococcus 284. A virus is isolated from a skin lesion. It is noted to produce cytopathogenicity in tissue culture and is photodynamically inactivated following exposure to dye neutral red. This virus will MOST likely be classified as a: A. Hepresvirus B. Poxvirus C. Adenovirus D. Reovirus 285. All of the following fungi can cause hair infection, EXCEPT: A. Epidermophyton floccosum B. Trichosporon beigelii C. Trichophyton mentagrophytes D. Microsporon canis 286. All of the following intestinal parasites are transmitted to man through the oral-fecal route, EXCEPT: A. Ascaris lumbricoides B. Ankylostoma duodenale C. Balantidium coli D. Entamoeba histolytica 287. Which of the following diseases is caused by a virus that is spread primarily by the fecal-oral route? A. Dengue B. Yellow fever C. Japanese-B encephalitis D. Poliomyelitis

289. Which of the following viruses will LEAST likely infect the intestinal tract as their initial site of infection? A. Mumps virus B. Poliovurus C. Hepatitis A virus D. Rotavirus 290. All of the following are obligate intracellular bacteria, EXCEPT: A. Rickettsia prowazekii B. Chlamydia psittaci C. Chlamydia trachomatis D. Legionella micdadei 291. A virus transmitted by insect bite is classified as: A. Neurovirus B. Enterovirus C. DNA virus D. Arbovirus 292. Which of the following is statements is LEAST correct regarding the nature of medically important viruses? A. Epstein-Barr virus is a non-enveloped virus with RNA as its genome B. Influenza virus is an enveloped virus with RNA as its genome C. Hepatitis B virus is an enveloped virus with DNA as its genome D. Poliovirus is a non-enveloped virus with RNA as its genome 293. Dipicolinic acid is a key component of: A. Bacterial flagella B. Eukaryotic cilia C. Eukaryotic flagella D. Bacterial spores 294. Which of the following statements is NOT true regarding bacterial spores? A. Most bacterial spores can survive in the soil for long periods B. Require temperatures above boiling point in order to be killed C. Are formed primarily by gram-negative cocci such as Neisseria D. Are formed primarily when the organisms have inadequate nutrients 295. Which of the following causes a subcutaneous fungal disease characterized by swelling of the sinus tracts with presence of sulfur granules? A. Mycetoma B. Aspergillus C. Sporothrix D. Cladosporium

296. Tinea vesicolor or Pityriasis versicolor is a superficial skin infection characterized by hypopigmented areas is caused by: A. Malassezia furfur B. Sporothrix C. Candida albicans D. Microsporum

297. Which of the following is the infective form of Schistosoma in man? A. Metacercariae in fish flesh B. Cercariae encysted in aquatic vegetation C. Cercriae liberated in water D. Procercoid larvae inside a fish

298. Which of the following viruses will LEAST likely infect WBCs as an important part of their pathogenesis? A. Cytomegalovirus B. Human immunodeficiency virus C. Epstein-Barr virus D. Rabies virus 299. The term “ringworm” is equally applicable in naming a condition caused by: A. Tinea flava B. Tinea circinata C. Tinea nigris D. Tinea versicolor

300. Which of the following parasites localizes in the urinary tract and can be seen in the urine of infected persons? A. Schistosoma japonicum B. Schistosoma haematobium C. Schistosoma mansoni D. Paragonimus westermani