BioSc221/325
Exam 5
Name ______________________________
Multiple choice. (1 point each) Choose the one best answer to each of the following questions.
____ Acetic acid bacteria
A. convert ethanol to acetic acid
B. convert acetic acid to vinegar
C. convert acetic acid to ethanol
D. convert raw vinegar to distilled vinegar
____ The endosymbionts that enable Riftia to survive in the harsh environment around hydrothermal vents are found in the
A. the gills
B. the plume
C. the sheath
D. the trophosome
____ The enzyme that enables Vibrio fischeri to produce light is called
A. oxidoreductase
B. fatty acid reductase
C. luciferase
D. bug lite
____ Buchnera aphidicola is a bacterial endosymbiont of aphids. It provides the aphid with amino acids such as tryptophan.
How does B. aphidicola manage to by-pass the feedback inhibition that normally prevents overproduction of amino acids?
A. The amino acid biosynthetic genes are present on a multicopy plasmid
B. They produce a modified form of tryptophan that can be used by the aphid but does not feedback inhibit biosynthesis.
C. They no longer have the genes that repress tryptophan biosythesis.
D. They are located in specialized cells called bacteriocytes.
____ Which of the following reactions of the nitrogen cycle is catalyzed only by microbes?
A. ammonification
B. denitrification
C. nitrogen fixation
D. nitrification
____ Babies are susceptible to infant botulism because
A. they tend to eat a lot of dirty objects
B. most babies are not breast fed
C. their microbiota is not yet established to protect them
D. their intestinal tract is designed to be more absorbent so they absorb the toxin easier
____ After processing, some of the activated sludge goes ___ while the rest goes ___.
A. back to the aerator/to the anoxic digester or the sludge pond
B. back to the primary system/ to the aerator
C. to the anoxic digester or sludge pond/ back to the primary system
D. back to the primary system/ to the tertiary digester
____ Rhizobia are attracted to the roothairs of plants by
A. bacteroids
B. leghemoglobin
C. flavonoids
D. infection threads
____ Which of the following is not a problem encountered when trying to use bacteria to produce large quantities of foreign
(i.e. human) protein?
A. Inclusion bodies made up of insoluble foreign protein are often formed.
B. Human genes have introns and bacterial genes do not.
C. Foreign proteins are often toxic for the bacterium.
D. Human genes are not arranged in operons like bacterial genes.
____ Which statement(s) is/are true?
A. Gram positive organisms dominate the microflora
B. Propionibacterium acne is a normal resident of the skin
C. Lipophilic yeasts are sometimes normal residents of the skin
D. all of the above are true
____ Which of the following is a characteristic of a secondary metabolite?
A. essential for growth and replication
B. biosynthetic enzymes are regulated along with primary metabolites
C. usually produced via simple pathways involving only a few steps
D. sensitive to growth conditions and growth stage
____ The production phase during the growth of an industrial microorganism is referred to as the
A. trophophase
B. idiophase
C. log phase
____ Which of the following regions of the gastrointestinal tract has both the largest population of bacteri and the greatest
species diversity?
A.
B.
C.
D.
ileum
jejunum
colon
duodenum
____ With increased levels of oxidizable materials, the BOD will
A.
B.
C.
D.
increase
decrease
remain the same
increase or decrease depending on the nature of the materials involved
____ Commercial production of antibiotic requires
A.
B.
C.
D.
E.
increased aeration via a device such as a sparger
a fermenter
an antifoam agent
all of the above
none of the above
____ Psuedomembranous colitis results from
A.
B.
C.
D.
eating honey contaminated with Clostridium dificile
extensive antibiotic therapy
food poisoning
hospital food
____ Mashing is a process by which
A.
B.
C.
D.
a precursor for beer or ale is made
a precursor for wine is made
the residue from a distilling process is turned into re-usable wastes
non-potable fermented products are manufactured
____ Ruminants obtain amino acids and vitamins from
A.
B.
C.
D.
grain
protein
grass
bacteria
____ Organisms that mineralize organic matter to gasses and minerals are called
A.
B.
C.
D.
primary producers
secondary producers
consumers
decomposers
____ Microorganisms are important in
A.
B.
C.
D.
anaerobic wastewater treatment
secondary wastewater treatment
decreasing BOD in water treatment
all of the above
____ Newly discovered antibiotics are tested for inhibitory activity against different types of microorganisms because
A.
B.
C.
D.
there will be a better chance to find inhibition
useful antibiotics rarely inhibit all kinds of microbes
they should not inhibit the normal flora
some of this activity may counter the effects of the antibiotic
____ The genes for apo-leghemoglobin are located in
A.
B.
C.
D.
plant DNA
bacterial DNA
mitochondrial DNA
both plant and bacterial DNA
____ The "normal" flora of adult humans is
A.
B.
C.
D.
constantly changing
commensalistic
the same on every individual
parasitic
____ As sewage and industrial pollution enter a river, the added organic matter can lead to
A.
B.
C.
D.
excesses in the amount of oxygen present
severe oxygen depletion
marked oxygen imbalance
noticible fluctuations in oxygen demands
____ A lichen is an example of a
A.
B.
C.
D.
symbiotic association
syntrophy
commensalism
parasitism
____ Growth of microbes in nature is very different than in the laboratory because
A.
B.
C.
D.
of poor nutrient distribution in nature
in the laboratory the cells are grown in minimal media
in the laboratory the bacteria are not grown at their optimal temperature
all of the above
____ Why would a luminescent bacterium be nonluminescent when free in seawater?
A.
B.
C.
D.
The O2 concentration is too low for luminscence.
There is not enough long-chain aldehyde.
Autoinducer does not accumulate.
It requires hemoglobin from the fish.
____ The primary producers at hydrothermal vents are
A.
B.
C.
D.
chemolithotrophs
photolithotrophs
chemoheterotrophs
photoheterotrophs
____ Fungi in lichens provide the algae that grow in them with
A.
B.
C.
D.
amino acids
water
inorganic nutirents
organic nutirents
____ Why do animals establish relationships with luminescent bacteria?
A.
B.
C.
D.
E.
mating
schooling
attracting prey
protection
all of the above
____ Bioconversion is used to produce which of the following products?
A.
B.
C.
D.
oral contraceptives
antibiotics
insulin
amino acids
____ Eutrophication of a lake can result from
A.
B.
C.
D.
increased salinity
removal of enrichment
increased nitrogen
all of the above
____ Which statement about industrial microbiology is false?
A.
B.
C.
D.
It includes the latest molecular techniques
It has been around since ancient times
It is the study of products that affect our lives.
It only involves genetic engineering today.
____ Which of the following is used to produce vinegar?
A.
B.
C.
D.
Acetobacter
Agrobacterium
Xanthomonas
Lactobacillus
____ An example of a secondary metabolite is
A.
B.
C.
D.
lactic acid
ethanol
streptomycin
acetic acid
____ Chlortetracycline is a ___ metabolite made during ___.
A.
B.
C.
D.
primary; trophophase
secondary; trophophase
primary; idiophase
secondary; idiophase
____ Salt is added to shredded cabbage to make sauerkraut in order to
A.
B.
C.
D.
add flavor to the final product
extract sugars from the plant
kill gram-negative contaminants
kill gram-positive contaminants
____ Bacteria in nature are found associated with biofilms with other microbes. The advantage of growing in a biofilm is __.
A.
B.
C.
D.
to avoid being washed away
increased access to nutrients
obtaining nutrients from the other trapped microbes
all of the above
____ Fermented malt is used to produce
A.
B.
C.
D.
whiskey
rum
vodka
sake
____ Which of the following is not an antibiotic producer?
A.
B.
C.
D.
streptococci
bacilli
fungi
actinomycetes
Short answer. (1 point each)
What is one reason beer making is more complex than wine making?
What kind of microbial enzyme is of interest to the detergent industry?
Briefly explain why food product such as sauerkraut are rarely contaminated with undesirable microorganisms?
Briefly explain what is a semi-synthetic antibiotic.
Briefly explain why one can often find a significant number of anaerobic microbes in the top few millimeters of topsoil even
though this is not an anoxic environment.
Short Essay Questions. Please answer three of the following four short essay questions (5 points each - 5 bonus points
possible for answering all 5 questions)
Describe three roles that the resident microbiota of the human body.
List five biotechnological applications of microorganisms and briefly explain the role of the microbes used in that process.
Briefly describe three ways that an industrial organism might be “modified” and the significance of those modifications.
List five parts of the human body that have a resident microbiota and briefly describe the characteristics of the organisms one
would find there.