STRAIGHTERLINE MICROBIOLOGY
FINAL TEST 2026 QUESTIONS WITH
CORRECT ANSWERS GRADED A+
◍ Cell walls are not typically possessed by ______..
Answer: protozoa
◍ Studies by Emil von Behring and Shibasaburo Kitasato demonstrated that
inactivated toxins can induce the synthesis of antitoxins in the blood of
rabbits. These antitoxins (antibodies) are the basis of... a. humoral
immunityb. cell-mediated immunityc. antibiotic immunityd.
phagocyte-mediated immunity.
Answer: a. humoral immunity
◍ The two major groups of helminths are the ______ and the ______..
Answer: roundworms; flatworms
◍ Which of the following is not true of conjugation?a. Involves direct contact
between cellsb. Transfers genes for drug resistancec. Transfers genes for
enzymes and adherence moleculesd. Involves the action of bacteriophagee.
The donor retains a copy of the transferred genes.
Answer: Involves the action of bacteriophage
◍ Who of the following first discovered that some blood leukocytes could
engulf disease-causing bacteria?a. von Behringb. Meisterc. Metchnikoffd.
Ivanowski.
Answer: c. Metchnikoff
◍ Which of the following properties is likely to be found in a pioneer
colonizer of a biofilm on an artificial joint implant?.
Answer: Surface structures for attaching to tissue
,◍ A bacterium is inoculated into a tube of thioglycollate and incubated. After
incubation, turbidity appears throughout, top to bottom, with the greatest
turbidty at the very top. This bacterium would be called a(n) ______..
Answer: facultative anaerobe
◍ Who is credited with developing a vaccine against chicken cholera?a.
Kochb. Pasteurc. Jennerd. Lister.
Answer: b. Pasteur
◍ The concept that living organisms arise from nonliving material is called...a.
biogenesisb. cell theoryc. spontaneous generationd. germ theory.
Answer: c. spontaneous generation
◍ An organic nutrient that cannot be synthesized by the organism and must be
provided is called a(n) ______..
Answer: growth factor
◍ Protists contain all of the following forms of life EXCEP
T. ..a. protozoab. fungic. slime moldsd. algae.
Answer: b. fungi
◍ Cells with a relatively simple cell morphology that do not have a true
membrane-delimited nucleus are called...a. prokaryotesb. eukaryotesc.
urkaryotesd. nokaryotes.
Answer: a. prokaryotes
◍ Humans can see objects as small as 0.1 mm. Leeuwenhoek's best
microscope could magnify objects to 300
X. Which of the following would be invisible using Leeuwenhoek's
microscope?.
Answer: Poliovirus, 30 nm
◍ The ribosomal RNA studies that led to the division of prokaryotic organisms
into the Bacteria and the Archaea were begun by...a. Pasteurb. Woesec.
Needhamd. Watson.
Answer: b. Woese
,◍ In a search for new antibiotics, a previously unknown organism has been
recovered from the soil. It is nonmotile and is composed of long threadlike
structures formed from nucleated cells. It is not-photosynthetic and absorbs
its nutrients. This organism will most likely be classified among the...a.
bacteriab. archaeac. eukaryotes (fungi)d. eukaryotes (protozoa)e. eukaryotes
(algae).
Answer: c. eukaryotes (fungi)
◍ If immersion oil was replaced with water, what would happen?a. The
refractive index would increase, improving resolutionb. The refractive index
of water would be greater than air but less than oil, improving resolution
less than oil.c. The refractive index of water would be less than that of air,
decreasing resolution.d. There would be no difference..
Answer: b. The refractive index of water would be greater than air but less
than oil, improving resolution less than oil.
◍ Prior to staining, smears of microorganisms are heat-fixed in order to...a.
allow eventual visualization of internal structures.b. ensure removal of dust
particles from the slide surface.c. attach it firmly to the slide.d. create small
pores in cells that facilitates binding of stain to cell structures..
Answer: c. attach it firmly to the slide.
◍ If the decolorizer is left on too long in the Gram-staining procedure,
gram-positive organisms will be stained __________ and gram-negative
organisms will be stained __________.a. purple; blueb. purple; colorlessc.
purple; pinkd. pink; pink.
Answer: d. pink; pink
◍ Which of the following is not associated with every virus?a. Envelopeb.
Capsomeresc. Capsidd. Nucleic acide. Genome.
Answer: Envelope
◍ Regions of a specimen with higher electron density scatter ___________
electrons and, therefore, appear __________ in the image projected onto the
screen of a transmission electron microscope.a. more; lighterb. more;
darkerc. fewer; darkerd. fewer; lighter.
, Answer: b. more; darker
◍ A diagram of the three domains (Bacteria, Archaea, Eukarya) proceeding
from the Last Universal Common Ancestor would show Archaea.
Answer: branching off the Domain Eukarya.
◍ In the Gram-staining procedure, the mordant is...a. iodine.b. safranin.c.
crystal violet.d. alcohol..
Answer: a. iodine.
◍ Acid-fast organisms such as Mycobacterium tuberculosis contain lipids
constructed from ________________in their cell walls.a. proteinsb.
carbohydratesc. mycolic acidsd. peptidoglycan.
Answer: c. mycolic acids
◍ Fatty acid methyl ester (FAME) analysis is particularly important in public
health because in this application, microbiologists seek to identify specific
microbial pathogens in ______.a. food and waterb. patient samplesc.
genomic analysisd. genetic diseases.
Answer: a. food and water
◍ Genomic DNA sequences seem to support the idea that the first eukaryotic
cell arose from within the _____ lineage.a. archaealb. bacterialc. virald. last
universal common ancestor (LUCA).
Answer: a. archaeal
◍ During aerobic cellular respiration, the final electron acceptor is ______..
Answer: oxygen
◍ The endosymbiotic theory has been developed to explain the emergence of
______..
Answer: eukaryotes
◍ An unrooted tree containing four unrelated species can become rooted by
addinga. a descendant group related to two of the species.b. an unrelated
outgroup.c. a distantly related outgroup.d. a descendant related to only one
of the species..
FINAL TEST 2026 QUESTIONS WITH
CORRECT ANSWERS GRADED A+
◍ Cell walls are not typically possessed by ______..
Answer: protozoa
◍ Studies by Emil von Behring and Shibasaburo Kitasato demonstrated that
inactivated toxins can induce the synthesis of antitoxins in the blood of
rabbits. These antitoxins (antibodies) are the basis of... a. humoral
immunityb. cell-mediated immunityc. antibiotic immunityd.
phagocyte-mediated immunity.
Answer: a. humoral immunity
◍ The two major groups of helminths are the ______ and the ______..
Answer: roundworms; flatworms
◍ Which of the following is not true of conjugation?a. Involves direct contact
between cellsb. Transfers genes for drug resistancec. Transfers genes for
enzymes and adherence moleculesd. Involves the action of bacteriophagee.
The donor retains a copy of the transferred genes.
Answer: Involves the action of bacteriophage
◍ Who of the following first discovered that some blood leukocytes could
engulf disease-causing bacteria?a. von Behringb. Meisterc. Metchnikoffd.
Ivanowski.
Answer: c. Metchnikoff
◍ Which of the following properties is likely to be found in a pioneer
colonizer of a biofilm on an artificial joint implant?.
Answer: Surface structures for attaching to tissue
,◍ A bacterium is inoculated into a tube of thioglycollate and incubated. After
incubation, turbidity appears throughout, top to bottom, with the greatest
turbidty at the very top. This bacterium would be called a(n) ______..
Answer: facultative anaerobe
◍ Who is credited with developing a vaccine against chicken cholera?a.
Kochb. Pasteurc. Jennerd. Lister.
Answer: b. Pasteur
◍ The concept that living organisms arise from nonliving material is called...a.
biogenesisb. cell theoryc. spontaneous generationd. germ theory.
Answer: c. spontaneous generation
◍ An organic nutrient that cannot be synthesized by the organism and must be
provided is called a(n) ______..
Answer: growth factor
◍ Protists contain all of the following forms of life EXCEP
T. ..a. protozoab. fungic. slime moldsd. algae.
Answer: b. fungi
◍ Cells with a relatively simple cell morphology that do not have a true
membrane-delimited nucleus are called...a. prokaryotesb. eukaryotesc.
urkaryotesd. nokaryotes.
Answer: a. prokaryotes
◍ Humans can see objects as small as 0.1 mm. Leeuwenhoek's best
microscope could magnify objects to 300
X. Which of the following would be invisible using Leeuwenhoek's
microscope?.
Answer: Poliovirus, 30 nm
◍ The ribosomal RNA studies that led to the division of prokaryotic organisms
into the Bacteria and the Archaea were begun by...a. Pasteurb. Woesec.
Needhamd. Watson.
Answer: b. Woese
,◍ In a search for new antibiotics, a previously unknown organism has been
recovered from the soil. It is nonmotile and is composed of long threadlike
structures formed from nucleated cells. It is not-photosynthetic and absorbs
its nutrients. This organism will most likely be classified among the...a.
bacteriab. archaeac. eukaryotes (fungi)d. eukaryotes (protozoa)e. eukaryotes
(algae).
Answer: c. eukaryotes (fungi)
◍ If immersion oil was replaced with water, what would happen?a. The
refractive index would increase, improving resolutionb. The refractive index
of water would be greater than air but less than oil, improving resolution
less than oil.c. The refractive index of water would be less than that of air,
decreasing resolution.d. There would be no difference..
Answer: b. The refractive index of water would be greater than air but less
than oil, improving resolution less than oil.
◍ Prior to staining, smears of microorganisms are heat-fixed in order to...a.
allow eventual visualization of internal structures.b. ensure removal of dust
particles from the slide surface.c. attach it firmly to the slide.d. create small
pores in cells that facilitates binding of stain to cell structures..
Answer: c. attach it firmly to the slide.
◍ If the decolorizer is left on too long in the Gram-staining procedure,
gram-positive organisms will be stained __________ and gram-negative
organisms will be stained __________.a. purple; blueb. purple; colorlessc.
purple; pinkd. pink; pink.
Answer: d. pink; pink
◍ Which of the following is not associated with every virus?a. Envelopeb.
Capsomeresc. Capsidd. Nucleic acide. Genome.
Answer: Envelope
◍ Regions of a specimen with higher electron density scatter ___________
electrons and, therefore, appear __________ in the image projected onto the
screen of a transmission electron microscope.a. more; lighterb. more;
darkerc. fewer; darkerd. fewer; lighter.
, Answer: b. more; darker
◍ A diagram of the three domains (Bacteria, Archaea, Eukarya) proceeding
from the Last Universal Common Ancestor would show Archaea.
Answer: branching off the Domain Eukarya.
◍ In the Gram-staining procedure, the mordant is...a. iodine.b. safranin.c.
crystal violet.d. alcohol..
Answer: a. iodine.
◍ Acid-fast organisms such as Mycobacterium tuberculosis contain lipids
constructed from ________________in their cell walls.a. proteinsb.
carbohydratesc. mycolic acidsd. peptidoglycan.
Answer: c. mycolic acids
◍ Fatty acid methyl ester (FAME) analysis is particularly important in public
health because in this application, microbiologists seek to identify specific
microbial pathogens in ______.a. food and waterb. patient samplesc.
genomic analysisd. genetic diseases.
Answer: a. food and water
◍ Genomic DNA sequences seem to support the idea that the first eukaryotic
cell arose from within the _____ lineage.a. archaealb. bacterialc. virald. last
universal common ancestor (LUCA).
Answer: a. archaeal
◍ During aerobic cellular respiration, the final electron acceptor is ______..
Answer: oxygen
◍ The endosymbiotic theory has been developed to explain the emergence of
______..
Answer: eukaryotes
◍ An unrooted tree containing four unrelated species can become rooted by
addinga. a descendant group related to two of the species.b. an unrelated
outgroup.c. a distantly related outgroup.d. a descendant related to only one
of the species..
