Ch. 32 Microbio

Leishmania parasites live within leukocytes. Which type of cell is most likely to harbor them? A. natural killer cells B. memory B cells C. macrophages D. plasma B cells

macrophages

Which fungal genus is correctly matched to the class of disease it causes? A. systemic mycosis: Candida B. subcutaneous mycosis: Microsporum C. systemic mycosis: Sporothrix D. superficial mycosis: Aspergillus

systemic mycosis: Candida

A major cause of helminthic infectious blindness is __________. A. schistosomiasis B. trichinosis C. onchocerciasis D. Bancroft's filariasis

onchocerciasis

What is the correct sequence of events for the life cycle of the pork tapeworm, T. solium?

1. Eggs are produced by adult tapeworms living in the definitive host 2. Eggs are released to the environment in the feces 3. Pigs eat grass contaminated, or fertilized, with human feces. 4. Inside the intermediate host, the eggs mature into larvae and encyst in the hosts muscles 5. The definitive host ingests the eggs and becomes infected

Why does Dr. Clark request stool samples for examination? Select all that apply. A. He will have the laboratory prepare the samples for an ova and parasite (O&P) exam. Fresh or preserved stool samples can be observed microscopically for the presence of parasites or their eggs/cysts. B. Dr. Clark is hoping to find whole adult parasitic worms in Michael's fecal matter. C. Tapeworms are pathogens of the gastrointestinal tract; as a natural progression of digestion some of the tapeworm pieces will be expelled along with fecal matter. D. The stool sample will tell Dr. Clark more information about the vegetables in Michael's diet.

1. He will have the laboratory prepare the samples for an ova and parasite (O&P) exam. Fresh or preserved stool samples can be observed microscopically for the presence of parasites or their eggs/cysts. 2. Tapeworms are pathogens of the gastrointestinal tract; as a natural progression of digestion some of the tapeworm pieces will be expelled along with fecal matter.

Which of the following could Tori's physician choose as a treatment for her yeast infection? Select all that apply. A. an oral narrow-spectrum antibiotic, such as penicillin G B. a topical over-the-counter ointment, such as clotrimazole or miconazole C. an antiviral medication, such as acyclovir D. a single oral dose of fluconazole

1. a topical over-the-counter ointment, such as clotrimazole or miconazole 2. a single oral dose of fluconazole

Which of the following infections are also caused by C. albicans? Select all that apply. A. genital warts B. fulminating disease C. oral thrush D. syphilis

1. fulminating disease 2. oral thrush

How do blastoconidia and chlamydoconidia produced by yeast differ from bacterial endospores? A. Blastoconidia and chlamydoconidia are male and female mating structures used for reproduction in yeasts, whereas bacterial endospores are asexual reproductive structures. B. Blastoconidida and chlamydoconidia are identical to endospores. C. Blastoconidia and chlamydoconidia are spore structures produced by budding in yeasts, whereas bacterial endospores are produced by bacteria under extreme conditions. D. Blastoconidia and chlamydoconidia are produced only by yeasts in extreme conditions, whereas bacterial endospores are asexual reproductive structures.

Blastoconidia and chlamydoconidia are spore structures produced by budding in yeasts, whereas bacterial endospores are produced by bacteria under extreme conditions.

Based on the lab results, which organism is most likely causing Tori's new symptoms? A. Candida albicans B. Gardnerella vaginalis C. Trichomonas vaginalis D. Sporothrix schenckii

Candida albicans

The visceral parasites that are of great concern to people with compromised immune systems include __________. A. Cryptosporidium B. Cyclospora C. Trichomonas D. Giardia

Cryptosporidium

Which of the following represents the MOST LIKELY route of transmission for Michael's infection? A. Airborne - Inhalation of parasitic eggs in the air B. Foodborne - Eating undercooked, unwashed, or otherwise contaminated food that contained parasitic propagules C. Waterborne - Swimming in a freshwater lake with his friends while he was in China D. Vectorborne - Bitten by a mosquito carrying parasitic larvae

Foodborne - Eating undercooked, unwashed, or otherwise contaminated food that contained parasitic propagules

Which of the following statements best describes why the treatment for Tori's fungal infection may result in side effects to her own cells? A. Fungal cells and human cells both reproduce via budding. B. Fungal cells and human host cells both have cell walls made of cellulose. C. Fungal cells and human cells have a nucleus, multiple organelles, and 80S ribosomes for protein synthesis. D. Fungal cells and human host cells both have flagella for movement.

Fungal cells and human cells have a nucleus, multiple organelles, and 80S ribosomes for protein synthesis.

Why do we see an increase in the levels of IgE antibody in Michael's serum? A. IgE is the class of antibodies involved in hypersensitivities such as allergies and parasitic infections. B. IgE is the class of antibodies found in secretions. C. IgE is the most abundant class of antibodies in serum D. IgE is the first class of antibodies to appear after exposure to an antigen.

IgE is the class of antibodies involved in hypersensitivities such as allergies and parasitic infections.

Amphotericin B is an antifungal medication. What might its mechanism of action be? A. It binds to ribosomes. B. It binds to ergosterol. C. It prevents synthesis of peptidoglycan cell walls D. It binds to phospholipids in fungal membranes.

It binds to ergosterol.

Entamoeba histolytica, transmitted by contaminated food, grows on and in the cells lining the intestine and later within the intestinal wall. This results in dysentery. What best describes the relationship between E. histolytica and its host? A. It is a commensalism. B. It is a parasitic relationship. C. It is a mutualistic relationship. D. It is amensalism.

It is a parasitic relationship.

You are examining a sample to determine whether there is a pathogen present that might explain symptoms in a patient. You find a unicellular organism that lacks mitochondria, having mitosomes instead. It has a flagellum and a nucleus. What is it? A. It must be a bacterium because it has a flagellum. B. It must be a eukaryotic protist because it has a nucleus. C. It could be a protist or an animal cell because it has a nucleus. D. It must be a bacterium because it has no mitochondria.

It must be a eukaryotic protist because it has a nucleus.

The human parasitic infection caused by a protozoan that enters through the nose is caused by __________. A. Naegleria fowleri B. Entoamoeba histolytica C. Ballantidium coli D. Giardia intestinalis

Naegleria fowleri

What is the treatment that Dr. Clark will most likely recommend? A. Oral rehydration to replace fluids because tapeworms cause excessive diarrhea which results in dehydration in the host. B. Praziquantel or albendazole, drugs that target eukaryotic parasites with minimal side effects in the host. C. Surgical removal of the tapeworms in Michael's intestinal tract. D. Dr. Clark will recommend doing nothing because the tapeworm infection is self-limiting and will eventually go away on its own.

Praziquantel or albendazole, drugs that target eukaryotic parasites with minimal side effects in the host.

Which of the following organisms is most likely the causative agent of Michael's tapeworm infection? A. Ascaris lumbricoides B. Taenia saginata C. Taenia solium D. Enterobius vermicularis

Taenia solium

Compare the anatomy of the tapeworm (Image C) to the anatomy of the roundworm (Image D). Given that both are parasitic worms, which of the following reasons best explains why the tapeworm is flat? A. Tapeworms utilize diffusion to absorb nutrients from the host's digestive system. B. The shape of the tapeworm is constrained to fit in small spaces, such as the intestinal tract. C. Tapeworms have a complex and differentiated digestive system. D. Tapeworms are hermaphroditic, and need to accommodate both male and female gonads.

Tapeworms utilize diffusion to absorb nutrients from the host's digestive system.

Which of the following best explains why Tori developed a new series of symptoms? A. The initial antibiotics were not successful in clearing the respiratory infection, so the organism disseminated to the genitourinary tract. B. The antibiotics that treated Tori's primary respiratory infection also removed some of her normal bacterial flora, resulting in an overgrowth of other organisms. C. Tori contracted a sexually transmitted infection that was not related to the primary respiratory infection. D. Tori's immune system was compromised because of her respiratory infection, and this resulted in a yeast infection.

The antibiotics that treated Tori's primary respiratory infection also removed some of her normal bacterial flora, resulting in an overgrowth of other organisms.

During malarial infection, splenomegaly can occur. What causes this? A. The spleen becomes enlarged in response to fever. B. The malarial sporozoites colonize the spleen and cause inflammation. C. The spleen filters the blood and destroys old erythrocytes. D. The spleen always enlarges in response to infection.

The spleen filters the blood and destroys old erythrocytes.

Which of the following choices matches a hemoflagellate to its proper insect vector? A. Trypanosoma cruzi: kissing bug B. Leishmania: tsetse fly C. Trypanosoma brucei: sandfly D. None of the listed responses is correct.

Trypanosoma cruzi: kissing bug

How do pseudohyphae in yeasts differ from vegetative hyphae in filamentous fungi? A. Yeasts use pseudohyphae as a means of obtaining nutrients, whereas filamentous fungi use vegetative hyphae as a means of reproduction. B. Yeasts use pseudohyphae to invade host tissue, whereas filamentous fungi use their vegetative hyphae for obtaining nutrients. C. Yeasts use pseudohyphae for obtaining nutrients, whereas filamentous fungi use their vegetative hyphae to invade host tissues. D. Yeasts use pseudohyphae as a means of sexual reproduction, whereas parasitic fungi use their hyphae to invade host tissue.

Yeasts use pseudohyphae to invade host tissue, whereas filamentous fungi use their vegetative hyphae for obtaining nutrients.

Malaria is caused by a protist that is transmitted by mosquitoes. During its life cycle, the protist goes through cycles of destroying erythrocytes. Which of the following medical consequences is most directly related to this cell damage? A. fever B. chills C. anemia D. headache

anemia

Which of the following is an example of a secondary systemic mycosis? A. amoebic dystentery, a gastrointestinal illness B. cryptococcosis that develops in the lungs of a patient with HIV/AIDS C. a Staphylococcus aureus infection on the surface of the skin D. a ringworm infection of the scalp

cryptococcosis that develops in the lungs of a patient with HIV/AIDS

Fungi that can grow in a yeast or a mold form depending on the conditions are termed __________. A. dimorphic B. morphic C. amphimorphic D. pleomorphic

dimorphic

Visceral leishmaniasis is __________. A. caused by Leishmania tropica B. never fatal C. caused by Leishmania donovani D. the most common form of leishmaniasis

caused by Leishmania donovani

Why was Dr. Clark worried about tapeworm infection in other body sites? Select all that apply. A. When tapeworm larvae escape the stomach, they can travel to other parts of the body such as muscles, the liver, the eye, and even the brain to form cysticerci. B. Once ingested, the eggs of T. solium migrate to multiple body sites where they develop into structures called hydatid cysts. C. When the eggs are ingested, the larvae hatch and enter the intestinal glands. As the worm grows, it makes its way to the intestinal lumen where it survives for years by feeding on blood from the host. D. The presence of T. solium in the brain can result in neurocysticercosis, a serious condition which has symptoms resembling those of brain tumors or epilepsy.

1. When tapeworm larvae escape the stomach, they can travel to other parts of the body such as muscles, the liver, the eye, and even the brain to form cysticerci. 2. The presence of T. solium in the brain can result in neurocysticercosis, a serious condition which has symptoms resembling those of brain tumors or epilepsy.

The Plasmodium life cycle is very complex, involving two hosts. Which of the choices shows the correct sequence of events in this cycle? 1. Red blood cells are infected. 2. Mosquito bite occurs. 3. Plasmodium enters the liver. 4. Red blood cells are destroyed. 5. Plasmodium grows and develops sporozoites. A. 2, 3, 1, 5, 4, 2 B. 3, 5, 1, 4, 2 C. 1, 5, 4, 3, 2, 1 D. 2, 5, 3, 1, 4, 2

2, 5, 3, 1, 4, 2