Microbiology Exam 4
Name ___________________________
Multiple choice. (1 point each) Choose the one best answer to each of the following questions.
_____ The size of the most useful RNA molecule for prokaryotic evolutionary studies is
a)
b)
c)
d)
5S
16S
18S
23S
_____ All eukaryotes contain
a)
b)
c)
d)
a membrane bound nucleus
mitochondria
hydrogenosomes
all of the above
_____ A habitat containing a methanogen is
a)
b)
c)
d)
anoxic and reduced
anoxic but not very reduced
reduced but not anoxic
aerobic
_____ Although the microsporidia and diplomonads are eukaryotic, they lack
a)
b)
c)
d)
mitochondria
a true nucleus
identifiable ribosomes
all of the above
_____ The most widely used molecular chronometer is
a)
b)
c)
d)
cytochrome C
ATPase
ribosomal RNA
heat shock proteins
_____ Protein synthesis studies using Sulfolobus (archaea), yeast (eukarya), and Escherichia coli
(eubacteria) indicate that the ribosomal proteins of _____ and _____ are more closely related to each other
than they are to the ribosomal proteins of _____.
a)
b)
c)
d)
archaea, eubacteria, eukarya
archaea, eukarya, eubacteria
eubacteria, eukarya, archaea
none of the above because the studies indicate these proteins all seem to be similar.
_____ Why are all methanogens fluorescent under ultraviolet light?
a)
b)
c)
d)
they have the electron carrier F420
methane is a fluorescent compound
sodium pumped out by the sodium pump gives off blue light
the combustion of methane gives off blue light
_____ The eukaryotic functional equivalent of the prokaryotic 16S rRNA is the
a)
b)
c)
d)
5S rRNA
16S rRNA (the same as the prokaryotic 16S rRNA)
18S rRNA
23S rRNA
_____ The difference between cellular and acellular slime molds is
a)
b)
c)
d)
cellular types form multinucleate spore bearing structures
cullular types form haploid amoeboe which fuse
acellular types form spores
acellular types form fruiting bodies from one giant multinucleate cell
_____ The archaezoan Trychonympha benefits the termite Reticulotermes by production of
a)
b)
c)
d)
methane
hydrogen
acetate
vitamins
_____ Eukaryotes have not acquired chloroplasts without acquiring mitochondria because
a)
b)
c)
d)
mitochondria give energy to chloroplasts
cells without mitochondria are probably oxygen-sensitive
cells without mitochondria are probably aerobic
they are anaerobic
_____ A gram positive microorganism has the following traits: filamentous, forms spores at the end of
mycelia, produces antibiotics, produces geosmin, is nutritionally versatile, yields compact "dusty" colonies
on agar culture media. These traits describe the genus
a)
b)
c)
d)
Streptomyces
Streptobacillus
Mycobacterium
Lactobacillus
_____ Which of the following characterize the Actinomycetes?
a)
b)
c)
d)
Filamentous growth.
Conidia on aerial hyphae.
Common inhabitants of soil.
All of the above.
_____ Amoeboflagellates are protozoa with
a)
b)
c)
d)
a dominant flagellar stage
a unique mechanism of pseudopod formation
both amoeba and flagellate stages in the life cycle
with life cycles linke to sexual recombination
_____ Enzymes from thermophiles are
a)
b)
c)
d)
used in PCR
used in laundry detergents
cheaper to use because less protein is required for the same amount of activity
all of the above
_____ A thin, crescent-shaped organism with a single flagellum originating from a basal body would most
likely be a member of the genus
a)
b)
c)
d)
Trypanosoma
Glossina
Entamoeba
Gambiense
_____ Which statement best describes the habitats of the fungi?
a)
b)
c)
d)
Most fungi are aquatic, primarily fresh water aquatic.
Most fungi are aquatic, primarily marine aquatic.
Most terrestrial fungi dwell in the soil or on dead plant material.
Most terrestrial fungi are plant or animal parasites.
_____ In archaea ether-linked lipids are found in
a)
b)
c)
d)
e)
methanogens
halophiles
sulfur-dependent thermophiles
all of the above
none of the above
_____ A predominant mode of catabolism among the anaerobic, extremely thermophilic archaea involves
a)
b)
c)
d)
e)
chlorophyll-based photosynthesis
light-stimulated proton translocation across the membrane via bacteriorhodopsin
reduction of nitrate
oxidation of sulfur
reduction of sulfur
_____ Which of the following unique cofactors found in methanogenic bacteria does not function as a
carbon carrier?
a)
b)
c)
d)
F420
methanopterin
methanofuran
Coenzyme M
_____ Group of archaezoan protists that include the disease causing microbie Giardia intestinalis.
a)
b)
c)
d)
parabasalians
amoeboflagellates
apicomplexa
diplomonads
_____ Which of the following about methanogens is false
a)
b)
c)
d)
they contribute to the warming of the planet
they are all obligate methane producers
they all have pseudomurein in their cell walls
they have unusual coenzymes for methanogenesis
_____ Phylogenetic trees based on RNA sequences indicate that
a)
b)
c)
d)
e)
choanoflagellates are closest to animals origins
green plants evolved from chlorophyte ancestors
amoebae arose from flagellated cells
both a and b
all of the above
_____ Which algae are probably most closely related to the plants?
a)
b)
c)
d)
diatoms
brown algae
green algae
euglenoids
_____ Kinetoplastids in some protozoans
a)
b)
c)
d)
aid them in photosynthesis
aid them in locomotion
contain nuclear DNA
contain mitochondrial DNA
_____ Plasmodium vivax
a)
b)
c)
d)
reproduces sexually in the red blood cells
reproduces sexually in the mosquito
reproduces sexually in the live
doe not reproduce sexually
_____ From 16S rRNA analysis we have learned that
a)
b)
c)
d)
e)
Archaea and Bacteria are closely related
photosynthesis evolved in the Archaea
mitochondria came from the Archaea
the prokaryotes constitute one fo the three kingdoms or domains of life
the prokaryotes constitute two of the three kingdoms or domains of life
_____ Giardia can be transmitted by
a)
b)
c)
d)
live protozoa in diarrhea
drinking sources contaminated with cysts
fluid replacement
all of the above
_____ The cytoskeleton in eukaryotic cells may be used to
a)
b)
c)
d)
maintain cell shape
move materials around inside a cell
capture prey
all of the above
_____ Molecular sequencing suggests that mitochondria arose from a group of prokaryotic organisms that
includes the
a)
b)
c)
d)
Agrobacterium and Rhizobium
Vibrio and Photobacterium
Aquifex
Escherichia and Salmonella
_____ All members of the genus Bacillus are known for ___.
a)
b)
c)
d)
their ability to break down sulfur-containing compounds.
their ability to form endospores
their ability to live in the absence of oxygen
the capsules they posses
_____ Euglenoids are close phylogenetic relatives of the
a)
b)
c)
d)
flagellated protozoa.
ciliated protozoa.
ameboid protozoa
sporozoans
_____ Which statement is true?
a)
b)
c)
d)
Conidia are asexual spores.
Ascospores are sexual spores.
Basidiospores are sexual spores.
all of the above are true.
_____ The apicomplexa are characterized by
a)
b)
c)
d)
obligate parasitism.
undulating motility in the adult stages.
external digestion of food particles.
all of the above
_____ Mitochondria
a)
b)
c)
d)
utilize the Calvin-Benson cycle.
utilize the citric acid cycle.
reduce organic compounds to CO2.
all of the above.
_____ The purple pigment found in bacteriorhodopsin is called ___.
a)
b)
c)
d)
pheophytin
carotenoid
bacterioruberin
retinal
_____ Photosynthetic halophiles use bacteriorhodopsin to
a)
b)
c)
d)
reduce NADP from electron donors in photosynthesis
change the configuration of retinal
expel protons outside the cell
maintain high internal salt concentration
_____ Group of primarily photosynthetic protists that are the cause of "red tides".
a)
b)
c)
d)
Algae
Diatoms
Dinoflagellates
Euglenoids
_____ Thermophiles have adapted to higher temperatures for growth by
a)
b)
c)
d)
synthesis of temperature-sensitive proteins
synthesis of special heat-tolerant proteins
synthesis of heat-stable DNA and RNA
growth in selective environments
_____ Hydrogenosomes are
a)
b)
c)
d)
intermediate forms of mitochondria
found in anaerobic bacteria
organelles in protozoa for oxidation of pyruvate
organelles in protozoa for anaerobic conversion of pyruvate to acetate and CO2
_____ Group of microbes that undergo a complex lifestyle including a slug and fruiting body stage and
serves as a model system for development.
a)
b)
c)
d)
diplomonads
slime molds
lichens
fungi
_____ Methanogens
a)
b)
c)
d)
produce methane as a part of their energy metabolism.
utilize methane as an energy source.
process and store methane as a part of their repair mechanisms.
do none of the above.
_____ Which internal eukaryotic membrane system is mismatched with its function in the cell?
a)
b)
c)
d)
e)
contractile vacuoles - expell water
nuclear membrane - contains DNA
endoplasmic reticulum - DNA synthesis
golgi apparatus - secretory protein processing
lysozomes - contain digestive enzymes
_____ Which statement(s) is/are not true of the organisms in the domain archaea?
a)
b)
c)
d)
These organisms lack peptidoglycan in their cell walls.
These organisms contain ether-linked lipids.
These organisms have simple RNA polymerases.
All of the above.
_____ The chloroplasts of red algae contain __, which is also the main light harvesting pigment found in
___.
a) phycobiliproteins/cyanobacteria
b) bacteriochlorophyl/ purple bacteria
c) bacteriorhodopsin/halobacteria
_____ Which statement is true?
a)
b)
c)
d)
The methanogens are obligate aerobes and the extreme halophiles are obligate anaerobes.
The methanogens are obligate anaerobes and the extreme halophiles are obligate aerobes.
Both the methanogens and the extreme halophiles are obligate aerobes.
Both the methanogens and the extreme halophiles are obligate anaerobes.
Short answer. (1 point each answer)
Filamentous fungi are known as _____________________.
The term used for the vegetative mass of the acellular clime molds is _______________________.
Why do most fungi have cell walls made of chitin instead of cellulose?
Lichens are organisms resulting from the symbiotic relationship between which two types of organisms?
In 16S RNA analysis, what is a "signature" sequence?
When determining the phylogenetic relationship between different organisms based on sequence analysis
why is it necessary to work with corrected differences instead of the actual percentage of differences?
Why is ribosomal RNA a "good" chronometer for measuring evolutionary relationships among organisms?
Short Essay Questions. Please answer 2 of the following 3 short essay questions (5 points each - 5 bonus
points possible for answering all three questions)
Describe the use of 16S rRNA sequences as a means of measuring the phylogenetic relationship between
different organisms. Include the features of this molecule, why this molecule is used and what information
has been obtained from 16S rRNA sequences analysis.
Describe the life cycle of the cellular slime mold Dictyostelium.
Compare and contrast bacteria, archaea and eukarya.