Microbiology: An Introduction, 13e (Tortora et al.)
Chapter 12 The Eukaryotes: Fungi, Algae, Protozoa, and Helminths
12.1 Multiple-Choice Questions
1) Which of the following statements regarding fungi is FALSE?
A) Most fungi are pathogenic for humans.
B) Fungi are eukaryotic heterotrophs.
C) Fungi reproduce by forming asexual or sexual spores.
D) Most fungi grow well in acidic culture condition.
E) Fungi tolerate low moisture conditions.
2) Which of the following statements about helminths is FALSE?
A) They are heterotrophic.
B) They are multicellular animals.
C) They have eukaryotic cells.
D) All are parasites.
E) Some have male and female reproductive organs in one animal.
3) Which of the following statements about the oomycote algae is FALSE?
A) They form hyphae.
B) They produce zoospores in a sporangium.
C) They cause plant diseases.
D) They have chlorophyll.
E) They reproduce sexually.
4) Seventeen patients in ten hospitals had cutaneous infections caused by Rhizopus. In all
seventeen patients, Elastoplast bandages were placed over sterile gauze pads to cover wounds.
Fourteen of the patients had surgical wounds, two had venous line insertion sites, and one had a
bite wound. Lesions present when the bandages were removed ranged from vesiculopustular
eruptions to ulcerations and skin necrosis requiring debridement. Fungi are more likely than
bacteria to contaminate bandages because they
A) are aerobic.
B) can tolerate low-moisture conditions.
C) prefer a neutral environment (pH 7).
D) have a fermentative metabolism.
E) cannot tolerate high osmotic pressure.
5) Which of the following statements regarding lichens is FALSE?
A) Lichens are a mutualistic relationship between a fungus and a protozoan.
B) Lichens represent a mutualistic relationship between a fungus and an alga.
C) Lichens are often the first life form to colonize rock or soil.
D) The algal partner produces carbohydrates that are absorbed by the fungal partner.
E) The fungal partner provides a means of attachment and protects the algal partner from
desiccation.
6) Which of the following pairs is mismatched?
A) Basidiomycota – basidiospores
B) Ascomycota – conidiospores
C) Zygomycota – sporangiospores
D) microsporidia – lack mitochondria
E) anamorphs – lack spores
Table 12.1
1-Arthroconidium 5-Chlamydoconidium
2-Ascospore 6-Conidiospore
3-Basidiospore 7-Sporangiospore
4-Blastoconidium 8-Zygospore
7) In Table 12.1, which of these spores are characteristic of Penicillium?
A) 1 and 2
B) 3 and 4
C) 2 and 6
D) 1 and 4
E) 4 and 6
8) In Table 12.1, which of these spores are characteristic of Rhizopus?
A) 1 and 2
B) 6 and 7
C) 2 and 8
D) 1 and 4
E) 7 and 8
9) In Table 12.1, which is a thick-walled spore formed as a segment within a hypha?
A) 1
B) 3
C) 5
D) 7
10) In Table 12.1, which of these spores are asexual spores?
A) 1, 4, 5, 6, 7
B) 2, 3, 6, 8
C) 1, 3, 5, 8
D) 2, 4, 6, 7, 8
11) Which of the following pairs is mismatched?
A) teleomorph – produces both sexual and asexual spores
B) dermatomycosis – fungal infection of the skin
C) dimorphic fungus – grows as a yeast or a mold
D) systemic mycosis – fungal infection of body organs
E) coenocytic hyphae – hyphae with cross-walls
12) Which of the following statements regarding protozoa is FALSE?
A) Protozoa are unicellular eukaryotes.
B) Nearly all protozoa cause disease.
C) Most protozoa reproduce asexually.
D) Protozoa are common in water and soil.
E) Some protozoan pathogens are transmitted by arthropod vectors.
13) In mid-December, a woman with insulin-dependent diabetes who had been on prednisone
fell and received an abrasion on the dorsal side of her right hand. She was placed on penicillin.
By the end of January, the ulcer had not healed, and she was referred to a plastic surgeon. On
January 30, a swab of the wound was cultured at 35°C on blood agar. On the same day, a smear
was made for Gram staining. The Gram stain showed large (10 µm) cells. Brownish, waxy
colonies grew on the blood agar. Slide cultures set up on February 1 and incubated at 25°C
showed septate hyphae and single conidia. The most likely cause of the infection is a
A) gram-negative bacterium.
B) dimorphic fungus.
C) parasitic alga.
D) yeast.
E) protozoan.
14) Which of the following tends to be more complex in a parasitic helminth than in free-living
helminths?
A) digestive system
B) nervous system
C) reproductive system
D) digestive and nervous systems
15) Which of the following statements is FALSE?
A) Fungi produce sexual spores.
B) Fungi produce asexual spores.
C) Fungal spores are used in identification of fungi.
D) Fungal spores are highly resistant to heat and chemical agents.
E) Fungal spores are for asexual or sexual reproduction.
16) Which of the following pairs are mismatched?
1. arthroconidium – formed by fragmentation
2. sporangiospore – formed within hyphae
3. conidiospore – formed in a chain
4. blastoconidium – formed from a bud
5. chlamydoconidium – formed in a sac
A) 1 and 2
B) 2 and 3
C) 2 and 5
D) 3 and 4
E) 4 and 5
17) Which of the following pairs is mismatched?
A) dinoflagellates – paralytic shellfish poisoning
B) brown algae – algin
C) red algae – agar
D) diatoms – petroleum
E) green algae – prokaryotic
18) Helminthic diseases are usually transmitted to humans by
A) respiratory route.
B) genitourinary route.
C) gastrointestinal route.
D) vectors.
E) aerosols.
19) All of the following are characteristic of the Platyhelminthes EXCEPT that they
A) are hermaphroditic.
B) are dorsoventrally flattened.
C) have highly developed digestive and nervous systems.
D) can be divided into flukes and tapeworms.
E) are multicellular animals.
20) In the malaria parasite life cycle, humans are the ________ host, while mosquitoes are the
________ host as well as the vector.
A) definitive; intermediate
B) intermediate; intermediate
C) temporary; final
D) vector; intermediate
E) intermediate; definitive
21) Three weeks after a river rafting trip, three family members experienced symptoms of
coughing, fever, and chest pain. During the rafting trip, the family had consumed crayfish that
they caught along the river banks. An examination of the patients’ sputum revealed helminth
eggs, and serum samples were positive for antibodies to Paragonimus. All of the family
members recovered following treatment with praziquantel. In the Paragonimus life cycle,
A) the crayfish are the definitive host and humans are the intermediate host.
B) humans are the definitive host and crayfish are the intermediate host.
C) both humans and crayfish are intermediate hosts.
D) both humans and crayfish are definitive hosts.
E) the source of the infection was the river water.
22) The encysted larva of the beef tapeworm is called a
A) redia.
B) cercaria.
C) cysticercus.
D) metacercaria.
E) proglottid.
23) Which of the following arthropods does NOT transmit diseases by sucking blood from a
human host?
A) lice
B) fleas
C) houseflies
D) mosquitoes
E) kissing bugs
24) Which of the following statements about algae is FALSE?
A) They use light as their energy source.
B) They use CO2 as their carbon source.
C) They produce oxygen from hydrolysis of water.
D) All are unicellular.
E) Some are capable of sexual reproduction.
25) Below are paired items referring to the heartworm Dirofilaria immitis. Which of the pairs is
mismatched?
A) dog – definitive host
B) dog – sexual reproduction
C) mosquito – vector
D) mosquito – definitive host
E) None of the pairs is mismatched.
26) All of the following are characteristic of algae EXCEPT which ONE of the following?
A) Most are photoautotrophs.
B) They are currently classified as plants.
C) They may be unicellular or multicellular.
D) Some produce harmful toxins.
E) They mostly live in aquatic habitats.
27) A definitive host harbors which stage of a parasite?
A) miracidium
B) cyst
C) adult
D) larva
E) All of the answers are correct.
28) What do tapeworms eat?
A) intestinal bacteria
B) host tissues
C) red blood cells
D) intestinal contents
E) plant matter
29) Giardia and Trichomonas are unusual eukaryotes because they
A) are motile.
B) lack mitochondria.
C) lack nuclei.
D) do not produce cysts.
E) do produce cysts.
30) The life cycle of the fish tapeworm is similar to that of the beef tapeworm. Which of the
following is the most effective preventive measure to avoid human infection?
A) salting fish before eating
B) refrigerating stored fish
C) cooking fish before eating
D) wearing gloves while handling fish
E) not swimming in fish-infested waters
31) Which of the following is the most effective control for malaria?
A) vaccination
B) treating patients
C) eliminate Anopheles mosquitoes
D) eliminate the intermediate host
E) None of these is an effective control.
32) In the microscope, you observe multinucleated amoeboid cells with sporangia that form
spores. This is a(n)
A) ascomycete.
B) cellular slime mold.
C) Euglenozoa.
D) tapeworm.
E) plasmodial slime mold.
33) You observe a mass of amoeba-like cells that swarm together, form a stalk, and produce
spores. This is a(n)
A) ascomycete.
B) cellular slime mold.
C) Euglenozoa.
D) tapeworm.
E) plasmodial slime mold.
34) Which of the following pairs is mismatched?
A) nematodes – complete digestive tract
B) cestodes – segmented body made of proglottids
C) trematodes – flukes
D) nematodes – many are free-living
E) cestodes – all are free-living
35) Which of the following is a nucleated, unicellular organism that, if you changed the
incubation temperature, would form filaments with conidiospores?
A) ascomycete
B) cellular slime mold
C) euglenozoa
D) tapeworm
E) plasmodial slime mold
36) Which of the following organisms is photoautotrophic protozoan?
A) oomycote
B) cellular slime mold
C) Euglena
D) Phytophthora
E) plasmodial slime mold
37) Which of the following pairs is mismatched?
A) tick – Rocky Mountain spotted fever
B) tick – Lyme disease
C) mosquito – malaria
D) mosquito – Pneumocystis
E) mosquito – encephalitis
38) Which of the following groups of algae does NOT produce compounds that are toxic to
humans?
A) diatoms
B) dinoflagellates
C) green algae
D) red algae
39) The cells of plasmodial slime molds can grow to several centimeters in diameter because
A) they have organelles.
B) they distribute nutrients by cytoplasmic streaming.
C) the large surface can absorb nutrients.
D) they form spores.
E) they have a mouth to ingest nutrients.
40) Assume you have isolated a multicellular heterotrophic organism that produces coenocytic
hyphae, motile zoospores, and cellulose cell walls. It is most likely a(n)
A) ascomycete fungus.
B) green alga.
C) oomycote alga.
D) tapeworm.
E) zygomycete fungus.
41) If a larva of Echinococcus granulosus is found in humans, humans are the
A) definitive host.
B) infected host.
C) intermediate host.
D) reservoir.
E) None of the answers is correct.
42) Ringworm is caused by a(n)
A) fungus.
B) cestode.
C) nematode.
D) protozoan.
E) trematode.
43) Yeast infections are caused by
A) Aspergillus.
B) Candida albicans.
C) Histoplasma.
D) Penicillium.
E) Saccharomyces cerevisiae.
44) All of the following are characteristic of lichens EXCEPT
A) they are arranged in foliose, fruticose, or crustose morphologies.
B) they are a major food source for tundra herbivores.
C) they are used as indicators of air pollution.
D) they are a symbiotic relationship between a fungus and a protozoan.
E) they serve as primary producers in rocky ecosystems.
45) You see acid-fast oocysts in a fecal sample from a patient who has diarrhea. What is the
MOST likely cause?
A) Cryptosporidium
B) diatoms
C) Entamoeba
D) Giardia
E) Taenia
46) A wolf kills a deer that is infected with ________ of Echinococcus granulosis in its liver and
eats it. After consuming the deer, the wolf’s intestine becomes filled with a number of ________
produced from scoleces. These eventually release eggs into the wolf’s intestines, which are
released in its feces.
A) hydatid cysts; proglottids
B) proglottids; hydatid cysts
C) cysticerci; proglottids
D) cercariae; cysticerci
E) hydatid cysts; cercariae
47) When we say that a human is a dead end host for a parasite, we mean
A) the human will die from the parasitic infection before being able to transmit it to another
organism.
B) the infected human is highly unlikely to transmit the infection to another organism.
C) humans lack the correct anatomical structures for the parasite to exit the body.
D) that the human isn’t capable of being infected by the parasite.
48) In the roundworms, the females have 1-2 hardened ________ on their posterior ends
A) genital pores
B) proglottids
C) cercariae
D) spicules
E) scoleces
49) Infecting more than 2 billion people worldwide, ________ are the most common causes of
chronic infectious diseases.
A) intestinal tapeworms
B) intestinal roundworms
C) fungi
D) algae
E) protozoa
50) The head of a tapeworm intestinal parasite is known as the ________.
A) proglottid
B) spicule
C) scolex
D) cysticerci
E) hydatid cyst
12.2 True/False Questions
1) Plasmogamy, karyogamy, and meiosis are stages of the fungal sexual life cycle.
2) Arthropod vectors are blood-sucking animals such as ticks, lice, and fleas that transmit
microbial pathogens.
3) Cercariae, metacercaria, and redia are all life cycle stages of trematodes.
4) The Platyhelminthes group includes roundworms, tapeworms, and flukes.
5) Some species of dinoflagellates produce neurotoxins that cause fish kills and red tides.
6) Both the cellular slime molds and the plasmodial slime molds are members of the phylum
Amoebozoa.
7) In helminth life cycles, the organism that harbors the adult sexually reproductive phase of the
parasite is called the intermediate host.
8) The sporozoite, merozoite, gametocyte, and ring stages are all part of the Plasmodium life
cycle.
9) The insect vectors have six legs and include spiders, ticks, mosquitoes, and lice.
10) Most cases of hookworm infection are acquired by ingestion of adult forms in contaminated
food or water.
12.3 Essay Questions
1) Provide an explanation for the complex life cycles exhibited by parasitic helminths. Cite
specific examples in your explanation.
2) Explain how the presence of algae can indicate either pollution or productivity of a body of
water.
3) Contrast the economic benefits and the harmful effects of fungi.
4) West Nile Virus is transmitted by mosquitoes as they take a blood meal. Flies can also
transmit pathogens, but not in the process of taking a blood meal. Differentiate the ways in which
flies and mosquitoes acquire and transmit infectious agents, and suggest 1-2 ways in which these
methods might be disrupted.
5) Slime molds are not molds. Based on their life cycles and processes, why do you think they
were originally given this incorrect name?