UPDATE 2026
Which of the following bacterial species are capable of converting nitrogen gas in the
atmosphere into compounds that other organisms can better utilize? - Answers
Rhizobium spp. : gram -, fix nitrogen
Of the bacterial species listed below, which do not utilize type IV secretion to transfer
DNA or proteins into eukaryotic cells? - Answers Neisseria gonorrhoeae Type V
secretion
After graduating from the University of Arizona you decided to become a benthic
marine biologist (studying the sea floor). Your have been using large dragnets to
collect sea floor marine life. In your first net you see a new species of anglerfish.
These fish have a light organ protruding in front of their mouth that is used to attract
prey fish in the dark depths of the ocean. You suspect that the light organ will contain
bacteria. What species from the list below do you suspect is most likely to have
colonized the light organ? - Answers (Alii)Vibrio fischeri - Aliivibrio fisheri;
produce visible light at high bacterial concentrations.
Hans Christian Gram is famous for developing a staining technique that separates
pathogenic bacteria into two roughly equal sized groups. He originally developed this
technique to differentiate two bacteria (one a bacillus and one a coccus) that were
causing the same disease. Which of the bacteria below was the bacillus in his
samples? - Answers Klebsiella pneumoniae : bacillus
The one thing you learned by your summer at sea (question #3) is that you do not like
water. You decided to return to the arid lands of Arizona where rivers only have water
flowing in them a few weeks out of the year. As fortune would have it, you have been
accepted into the UofA medical school. In your surgical rotation you will be learning
under the tutelage of Dr. Yavan Knowsomuch. On the first day with her, Dr.
Knowsomuch offhandedly remarks that her patients keep developing colitis after they
are discharged from her care. What species of bacteria do you suspect is causing these
symptoms? - Answers Clostridium difficile :colitis is a chronic, inflammatory bowel
disease
Robert Koch was one of the scientists in the late 19th century involved in developing
the Germ Theory. This theory states that diseases are caused by microscopic
organisms. Dr. Koch's lasting contribution to this theory was a systematic approach
,for identifying the microbial cause of a disease. We call this approach Koch's
Postulates. What were the declarative statements? - Answers a. You must find the
microbe in all cases of the disease.
b. You must be able to grow the microbe in a pure culture.
c. The pure culture must be able to cause the same disease in a new individual.
d. You must be able to re-isolate the original organism from individual infected in
part C.
True or False - Koch's Postulates have been used to show that all known diseases are
microbial in origin. - Answers False: Not known, only a method to prove what causes
disease. Not all diseases are microbial in origin; example: genetic diseases.
Which scientist is remembered for having developed the first microscope that could
resolve microorganisms? Lecture - Answers Dr. Antonie van Leeuwenhoek:
compound microscope
Which domain of life contains microorganisms - Answers a. Eubacteria
b. Eukaryotes
c. Archaea
True or False - The human body contains 10 times more prokaryotic cells than
eukaryotic cells. - Answers True: We have more microorganisms on our bodies than
our own cells.
Clostridium botulinum is a Gram-positive spore-forming bacterium that produces a
toxin that can block the release of neurotransmitters from human neurons. The
purified toxin has been shown to be useful in the treatment of which of the following
diseases:
A. Aging
b. Diarrhea
c. The flu
d. Alcoholism
e. Botox will not prevent or treat any of these diseases - Answers e. Botox will not
prevent or treat any of these diseases
I am sure you took the time to study osmosis. Here is your chance to be rewarded.
What would happen to a bacterial cell if you placed it in an isotonic solution? -
Answers Nothing would happen to the bacterial cell. because of cell wall
, Which of the following statements best characterizes the role of ATP in active
transport? - Answers ATP hydrolysis generates the energy to move a compound from
a low concentration outside the cell into the high concentration inside the cell
When cyanobacteria first evolved photosynthesis (about 2.3 billion years ago), they
killed off most life on earth. What metabolic byproduct of cyanobacteria
photosynthesis killed off most of the other organisms? - Answers Oxygen gas (O2)
Which of the following statements about the bacterial glycocalyx is correct? Lecture 3
Slide 24-25
a. Some bacteria, including Klebsiella pneumoniae, have a highly organized
glycocalyx - capsule - that can function to protect the bacteria from the host immune
system.
b. Some bacteria secrete protein via the glycocalyx complex between the inner and
outer membrane.
c. Some bacteria utilize the glycocalyx for a type motility known as twitching motility
d. All of the above are correct statements about bacterial glycocalyx. - Answers d. All
of the above are correct statements about bacterial glycocalyx.
What is the fate of the mother cell during bacterial sporulation after the endospore is
released? - Answers The mother cell is sacrificed in order to allow the endospore to
escape.
What is the process of bacterial communication by which bacteria are able to
determine the number of proximal microorganisms? - Answers Quorum sensing
Which of the following statements about the central dogma is not correct? Lecture 4
slide 11
a. DNA stores information to direct protein synthesis and passes that information
from generation to generation.
b. RNA is a less stable intermediary that forms a template for protein synthesis.
c. Ribosomes synthesize proteins by polymerizing amino acids in an order determined
by an RNA template
d. RNA polymerase creates a complementary sequence of RNA from a DNA
template.
e. All of the above are correct. - Answers e. All of the above are correct.