Mastering Micro Ch. 31B
c.
Which of the following can be stored for the longest period of time without suffering spoilage? a. perishable food b. semiperishable food c. nonperishable food d. all of the above.
d.
Which of the following choices matches a hemoflagellate to its proper insect vector? a. Leishmania: tsetse fly b. None of the listed responses is correct. c. Trypanosoma brucei: sandfly d. Trypanosoma cruzi: kissing bug
a.
Which of the following is an example of a secondary systemic mycosis? a. cryptococcosis that develops in the lungs of a patient with HIV/AIDS b. amoebic dystentery, a gastrointestinal illness c. a Staphylococcus aureus infection on the surface of the skin d. a ringworm infection of the scalp
b.
Which of the following is considered an opportunistic pathogen? a. Plasmodium vivax b. Candida albicans c. Toxoplasma gondii d. Trichomoniasis vaginalis
d.
A major cause of helminthic infectious blindness is __________. a. Bancroft's filariasis b. schistosomiasis c. trichinosis d. onchocerciasis
a.
Flour and sugar are classified as ____________ foods. a. nonperishable b. selectively perishable c. highly perishable d. semiperishable
d.
Fungi that can grow in a yeast or a mold form depending on the conditions are termed __________. a. pleomorphic b. morphic c. amphimorphic d. dimorphic
a.
The Campylobacter species are a. microaerophiles. b. facultative anaerobes. c. anaerobes. d. aerobes.
c.
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. 1, 5, 4, 3, 2, 1 b. 2, 3, 1, 5, 4, 2 c. 2, 5, 3, 1, 4, 2 d. 3, 5, 1, 4, 2
c.
The microorganism Cryptosporidium parvum is a a. fungus. b. virus. c. protozoan. d. bacterium.
b.
Vinegar is actually dilute a. sulfuric acid. b. acetic acid. c. phosphoric acid. d. hydrochloric acid.
d.
What is the infective form of Entamoeba histolytica and Giardia intestinalis? a. sporozoites b. trophozoites c. merozoites d. cysts
b.
What is the term used for the filamentous body found in many fungal species? a. dikaryote b. mycelium c. protonema d. gametophyte
b.
What items are routinely irradiated in the United States? a. fish b. spices c. fresh fruits d. canned foods
c.
ALL fungal infections can broadly be termed a. systemic. b. benign. c. mycoses. d. superficial.
b.
Enteric bacteria such as Salmonella, Shigella, and Escherichia often contaminate and spoil a. fruits. b. meat. c. vegetables. d. milk and milk products.
c.
Indigenous spoilage organisms are particular to certain foods mostly because of a. water availability. b. environmental properties c. available nutrients. d. microbial competition.
b.
Leishmania parasites live within leukocytes. Which type of cell is most likely to harbor them? a. memory B cells b. macrophages c. plasma B cells d. natural killer cells
a.
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. anemia b. fever c. headache d. chills
a.
Many fungi produce ________ that can cause significant disease. a. mycotoxins b. cellulases c. endotoxins d. chitinases
d.
Pickling is a type of food preservation utilizing a. basic substances. b. irradiation. c. lyophilization. d. weak acids
a.
Staphylococcus aureus enterotoxins tend to be a. heat-stable. b. heat-tolerant if other conditions are favorable. c. heat-labile. d. unpredictable with regard to heat.
b.
Superficial mycoses are caused by a group of fungal pathogens called __________. a. dimorphic b. dermatophytes c. dermatologic d. dematiaceous
a.
The visceral parasites that are of great concern to people with compromised immune systems include __________. a. Cryptosporidium b. Cyclospora c. Giardia d. Trichomonas
a.
Trichomoniasis vaginalis is a sexually transmitted disease that can also survive on moist surfaces and in urine for several hours. As a result, trichomoniasis a. can be spread by contact with contaminated toilet seats, sauna benches, and towels. b. is not a good candidate for eradication. c. is difficult to treat. d. is more common in males.
a.
Giardia cysts are able to withstand a. chemical disinfection. b. clarification. c. filtration. d. chemical disinfection, filtration, and clarification.
c.
Amphotericin B is an antifungal medication. What might its mechanism of action be? a. It binds to ribosomes. b. It binds to phospholipids in fungal membranes. c. It binds to ergosterol. d. It prevents synthesis of peptidoglycan cell walls
b.
Athlete's foot is an example of a a. protozoal infection. b. superficial fungal infection. c. superficial parasitic infection. d. hypersensitivity reaction.
b.
Azole medications inhibit the production of ergosterols. Which infection would they be most effective against? a. a bacterial infection b. a ringworm infection of the scalp c. a tapeworm d. malaria
d.
The organism causing giardiasis is a a. type of yeast. b. retrovirus. c. gram-negative spirochete. d. flagellated protozoan.
b.
The pH of most foods is a. basic. b. neutral or acidic. c. acidic. d. neutral or basic.
a.
The pH of most foods is a. neutral or acidic. b. acidic. c. neutral or basic. d. basic.
d.
Clostridium botulinum is a _________ that produces an ________. a. gram-negative rod / exotoxin. b. gram-positive rod / endotoxin. c. endospore-forming rod / endotoxin. d. endospore-forming rod / exotoxin.
a.
Cryptosporidium parvum oocysts are highly resistant to a. chlorine. b. heat. c. filtration. d. desiccation.
b.
Naegleria fowleri is a free-living ________ that causes infection by ________. a. protist / entering the vagina in women, the prostate and seminal vesicles of men, or the urethra of both males and females b. amoeba / entering through the nose and burrowing into the brain c. fungus / entering the lungs when contaminated soil is disturbed d. flagellated protist / crossing the intestinal mucosa into the blood
d.
The degree of susceptibility a food has to microbial activity is determined by (its) a. chemical characteristics. b. physical characteristics. c. water content. d. all of the above.
b.
The principle behind salt or sugar preservation is a. to introduce a mechanical barrier to microbial invasion. b. to reduce water availability. c. to introduce a microbicide in anticipation of contaminating bacteria or fungi. d. to accomplish all of the above, depending on the food being preserved.
d.
The human parasitic infection caused by a protozoan that enters through the nose is caused by __________. a. Entoamoeba histolytica b. Ballantidium coli c. Giardia intestinalis d. Naegleria fowleri
b.
The most common method of contracting a systemic mycosis is through __________. a. person-to-person contact b. inhalation c. sexual contact d. ingestion
a.
The most common source of individual foodborne botulism outbreaks are due to consumption of a. nonacid, home-canned vegetables. b. honey. c. egg and meat salads. d. diary products.
d.
The rate of contaminant microbial growth during the exponential phase depends on a. temperature. b. the nutrient value of the food. c. other growth conditions. d. all of the above.
d.
When solute is added to food products, the water activity a. initially increases and then decreases. b. remains the same. c. increases. d. decreases.
a.
Which of these organisms has hyphae? a. a bread mold b. an amoeboid protozoan c. a Staphylococcus aureus bacterium d. rotifers
b.
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 no mitochondria. 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 a flagellum.
