Microbiology Multiple Choice Questions on “Some Fungi of Special Interest”.
1. Which fungi causes black wart disease of potato?
A. Saprolegnia parasitica
B. Synchytrium endobioticum
C. Rhizopus stolonifer
D. Saccharomyces cerevisiae
Answer: B
Clarification: Synchytrium endobioticum is the most serious parasite of the class Chytridiomycetes that causes black wart disease of potato. The dark warts on the potatoes are galls in which the host cells have been stimulated to divide by the fungus.
2. Zygomycetes have which type of mycelia?
A. nonseptate
B. septate with uninucleate
C. septate with multi muclei
D. white,nonseptate
Answer: D
Clarification: Morphologically, the mycelia of Zygomycetes are usually white or gray and are nonseptate.
3. In the life cycle of Rhizopus stolonifer,when the protoplasts and nuclei of both gametangia coalesce, the structure is known as ________________
A. progametangia
B. coenozygote
C. zygospore
D. zygote
Answer: B
Clarification: The walls between two gametangia dissolve and their protoplasts coalesce. Nuclei of both mating types fuse in pairs, producing many zygote nuclei. The structure that contains them is then called a coenozygote.
4. Schizosaccharomyces versatilis is isolated from ________________
A. grape juice
B. cheese
C. honey
D. beer
Answer: A
Clarification: Schizosaccharomyces versatilis is isolated from grape juice. It grows like yeast but it can also form a true mycelium.
5. Legitimate copulation refers to ___________________
A. fusion between cells of same mating type
B. fusion between cells of different mating type
C. no fusion
D. different sex cells are present within the same body
Answer: B
Clarification: Fusion normally occurs only between cells of difffering mating types, a process termed as legitimate copulation. Such fusions result in diploid cells which form asci containing viable ascospores.
6. Neurospora sp. is important for the study of _____________________
A. human diseases
B. antibiotics
C. genetics and metabolic pathway
D. plant diseases
Answer: C
Clarification: Neurospora sp. which belongs to the class Ascomycetes is of particular interest to biologists because of its wide use in the study of genetics and metabolic pathways. Some species are also responsible for food spoilage and some are used in industrial fermentation.
7. Cryptococcosis is a disease of ________________
A. bacterial infection
B. parasitic infection
C. viral infection
D. mycotic infection
Answer: D
Clarification: Cryptococcus neoformans is an important basidiomycetous pathogen of humans, causing cryptococcosis, a generalized mycotic infection involving the bloodstream as well as lungs, central nervous system and other organs.
8. Aspergillus niger is used in the production of _______________
A. cheese
B. citric acid
C. gluconic acid
D. citric acid and gluconic acid
Answer: D
Clarification: It is an economically important fungi because they are used in a number of industrial fermentations, including the production of citric acid and gluconic acid in abundance.
9. Endocarditis is caused by which of the following fungi?
A. Candida albicans
B. Penicillium notatum
C. Penicillium chrysogenum
D. Agaricus campestris
Answer: A
Clarification: Candida albicans is often isolated from warm-blooded animals, including humans and becomes pathogenic and causes many serious infections. Endocarditis is caused by this organism and it is an infection of the heart.
10. What do you mean by hypertrophy?
A. repeated cell division
B. infection by zoospore
C. increase in cell volume
D. decrease in cell volume
Answer: C
Clarification: In the wart disease of potato, when the host cell is infected by a zoospore, it reacts by undergoing hypertrophy,i.e., an increase in cell volume, and adjacent cells also enlarge to form the characteristic rosette.
11. Which of the following fungi causes severe epidemic of disease among fish in the natural environment?
A. Saprolegnia ferax
B. Saprolegnia parasitica
C. Neurospora crassa
D. Neurospora sitophila
Answer: B
Clarification: Species of Saprolegnia are common in soil and fresh water; hence they are commonly called water molds. S.parasitica causes severe epidemics of disease among fish in the natural environment.
12. Reproductive organs are formed on the rhizoidal hyphae.
A. True
B. False
Answer: B
Clarification: The rhizoidal hyphae enter the substratum and serve to anchor the organism and to absorb nutrients, and the branched hyphae is the one on which reproductive organs are formed.
13. Rhizopus produces clusters of rootlike holdfasts called _____________
A. stolons
B. hyphae
C. runners
D. rhizoids
Answer: D
Clarification: The molds produce clusters of rootlike holdfasts called rhizoids. They also produce stolons or runners capable of taking root where that may give rise to new organisms.
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