In Class Questions Flashcards
The first microscope was developed in the 1800s
F
1600s by Robert Hooke
A typical bacterium has far more ribonucleotides than deoxyribonucleotides (by weight).
T
The first cells/organisms to arise on earth were likely phototrophic algae.
F
Organic molecules like amino acids are only produced by organisms.
F
Remember the experiments by Stanley Miller
In some cases a population can consist of multiple species.
F
RNA probably evolved before DNA.
T
__________ was primarily responsible for identifying the domain Archaea.
Carl Woese
All prokaryotes are microorganisms.
T
The largest known bacteria are visible to the naked eye.
T
Which disease has been fully eradicated (no new cases) by the efforts of microbiologists and public health workers?
Smallpox
Where does the current COVID-19 pandemic rank in terms of global pandemics to date with the highest estimated death toll?
8
So far there have been 4,541,115 reported, and 7–13 million estimated deaths
It is advantageous for a bacterium living in a nutrient poor body of water (e.g. the ocean) to be large, not small
F
The largest known bacterium is visible to the naked eye
T
It is advantageous for a bacterium living in a nutrient poor body of water (e.g. the ocean) to be small, not large
T
The nucleoid in bacteria is housed packaged inside a lipid layer
F
Prokaryotes don’t have nuclei!!
If you are a bacterium and lack MreB, what is your cell shape?
Coccus
A rod shaped bacterium with a tuft of flagella on one end is termed:
Lophotrichus
Bacteria consume ATP to power flagella
F
The S layer is a strong pure polysaccharide sheet of armour around some bacteria.
F
Approximately ½ of all “species” of bacteria in the world has been isolated in pure culture
F
Which of the following is the diffusion barrier in bacteria?
Cytoplasmic membrane
Protein secretion requires ATP energy
T
Ester bonds connect the hydrophilic and hydrophobic ends of bacterial phospholipids that make up the cytoplasmic membrane
T
Peptidoglycan makes up the bacterial cytoplasmic membrane.
F
Gram (-) bacteria can harness proton gradients/proton motive force across their outer membranes/ the LPS layer
F
They use proteins such as Porin Trimer and Ton B protein to transfer h2o and diffusion of nutrients (porins) and catalyze active transport (Ton B)
Porins - diffusion nutrient and water transport
TonB- catalyze active transport
A rod shaped bacterium with a tuft of flagella on one end is termed:
Peritrichous
Atrichous
Monotrichous
Lophotrichus
Amphitrichous
Lophotrichus
Bacteria consume ATP to power flagella
True
False
F
The S layer is a strong pure polysaccharide sheet of armour around some bacteria.
True
False
F
Approximately ½ of all “species” of bacteria in the world has been isolated in pure culture.
True
False
F
Halobacterium is a genus of Archaea
True
False
T
Halobacteria were discovered and described before it was accepted that the Archaea were a unique domain.
Unlike in the outer membrane/LPS layer in Gram (-) bacteria, there is at least one case where an archaeon can generate ATP across an outer membrane.
True
False
T
The antimicrobial compound lysozyme will kill dividing Archaea.
True
False
F
Archaeal infections are very difficult to treat in humans
True
False
F
Methanogens are obligate aerobes
True
False
F
Why is it thought that mitochondria are ancestors of the Alphaproteobacteria?
They “look” like bacteria (size and shape)
They use FtsZ to divide
They divide semi-automonously
They contain rRNA genes that are related to Alphaproteobacteria
All of the above
All of the above
Cytoplasmic membranes of eukaryal microorganisms contain more proteins than in prokaryotes
True
False
F
Bacterial flagella are powered by ATP
True
False
F
Which bacterial protein is a homologue to actin-based microfilaments?
FtsZ
ParM
MreB
None of the above
MreB
Dynein proteins:
Move eukaryal flagella
Move eukaryal cilia
Grab, pull, and release microtubules in the axoneme structure
All of the above
All of the above
Mitosis in eukaryal microorganisms only duplicates 1n not 2n cells
True
False
F
All eukaryal microorganisms have a cell wall
True
False
F
Antibiotics that target the ribosomes in eukaryal microbes do not harm humans.
True
False
F
Which of the following never makes up (a) viral genome(s)?
ssDNA
dsDNA
ssRNA
dsRNA
None of the above
None of the above
The viral envelope:
Is present in all viruses
Is made up of cytoplasmic or other organelle membranes from the host
Is characteristic of “naked” viruses
All of the above
Is made up of cytoplasmic or other organelle membranes from the host
Viruses typically can’t infect intact plant leaves easily.
True
False
T
Some viruses can carry out translation without the use of host ribosomes.
True
False
F
Like with organisms, rRNA sequences are the most robust way to identify and classify viruses/phages.
True
False
F
Remember- they don’t have ribosomes
Which is always a product of phototrophy?
Fixed CO2/organic matter
Proton motive force
O2
All of the above
Proton motive force
The Calvin cycle is the only pathway for C fixation in photosynthetic organisms.
True
False
F
All glycolytic pathways produce the same number of ATPs
True
False
F
The EMP pathway might be the one one you learned in earlier bio classes, but others exist!
Which is a pathway/strategy for re-oxidizing NADH?
Glycolysis
TCA cycle
Fermentation
Respiration
Both C and D
E
Which is a major source of macromolecule precursors/subunits?
Electron transport chains
Fermentation reactions
The TCA cycle
All of the above
C
Unlike glycolysis, cellular respiration always needs O2 to proceed.
True
False
F
A chemolithotrophic bacterium does not need to use glycolytic or citric acid cycle pathways to carry out cellular respiration.
True
False
T
A chemolithoautotroph gets its electrons/energy from reduced minerals and its carbon from CO2.
True
False
T
A microaerophilic microorganism is exceptionally small (relative to other microbes) and uses atmospheric levels of O2 as a terminal electron acceptor.
True
False
F
Microbes from which environment might be most likely to degrade agar?
Lake water
Marine water
Human large intestine
Soil
B
Halobacterium is a genus of Archaea
True
False
I don’t know
F
Unlike in the outer membrane/LPS layer in Gram (-) bacteria, there is at least one case where an archaeon can generate ATP across an outer membrane.
True
False
T
The antimicrobial compound lysozyme will kill dividing Archaea.
True
False
F
Archaeal infections are very difficult to treat in humans
True
False
F
There are no archaeal human pathagens known.
Methanogens are obligate aerobes
True
False
F
Why is it thought that mitochondria are ancestors of the Alphaproteobacteria?
They “look” like bacteria (size and shape)
They use FtsZ to divide
They divide semi-automonously
They contain rRNA genes that are related to Alphaproteobacteria
All of the above
E
Cytoplasmic membranes of eukaryal microorganisms contain more proteins than in prokaryotes
True
False
F
Bacterial flagella are powered by ATP
True
False
F
Which bacterial protein is a homologue to actin-based microfilaments?
FtsZ
ParM
MreB
None of the above
C
Dynein proteins:
Move eukaryal flagella
Move eukaryal cilia
Grab, pull, and release microtubules in the axoneme structure
All of the above
D
Mitosis in eukaryal microorganisms only duplicates 1n not 2n cells
True
False
F
All eukaryal microorganisms have a cell wall
True
False
F
Antibiotics that target the ribosomes in eukaryal microbes do not harm humans.
True
False
F
Which of the following never makes up (a) viral genome(s)?
ssDNA
dsDNA
ssRNA
dsRNA
None of the above
E
The viral envelope:
Is present in all viruses
Is made up of cytoplasmic or other organelle membranes from the host
Is characteristic of “naked” viruses
All of the above
B
Some viruses can carry out translation without the use of host ribosomes.
True
False
F
Like with organisms, rRNA sequences are the most robust way to identify and classify viruses/phages.
True
False
F
Remember- they don’t have ribosomes!
In the field of epidemiology, increased prevalence of a disease in a population is a clear signal that disease control and treatment are not effective.
F
Koch’s postulates are universally accepted as for linking a microbe to a disease:
F
Morbidity refers to the death rate associated with a disease.
F
Which pathogen strategy involves shifting surface proteins to evade host defenses?
Capsule formation
Antibody attack
Antigenic variation
None of the above
Antigenic variation
A zoonotic pathogen is one that causes disease in animals kept in captivity
F
Symbiotic mycorrhizal fungi help many plants use N2 from the atmosphere with nitrogenase enzymes.
F
Only prokaryotes can fix N..
What term describes a test animal that has a defined digestive tract microbial community?
Gnotobiotic
Germ free
Cecal
Rotobiotic
Gnotobiotic
Mutualistic microbes in the human colon are attached to intestinal epithelial cells.
F
A ‘meta analysis’ in scientific literature refers to compiling others’ published results and analyzing the collective outcomes.
T
Initial digestion by microorganisms vs digestive enzymes and acids are typical of which type of digestive system
Colonic
Cecal
Ruminant
Fermentative
Ruminant
All of the methane produced by methanogens ultimately enters the atmosphere and contributes to the greenhouse effect.
F
Denitrification is chemorganoheterophic process, with nitrate is used as the terminal electron acceptor to oxidize organic matter
T
Changing activities of microorganisms in the environment under global climate change has a large potential to further influence the global greenhouse effect.
T
The stomach is always a sterile environment (no living microbes).
F
Most microorganisms in the environment live alone in isolated populations.
F
Metagenomic analysis refers to the analysis of DNA of a single microbe (or other organism, for that matter).
F
What (instead of species) refers to the different types of organisms found in many microbial communities in the environment?
Approximated species
Pseudospecies
Strain
Operational taxonomic unit
Operational taxonomic unit
PCR is used to make many copies of a particular section of DNA.
T
All other things equal, a lake or section of coastal marine water is less healthy when nutrient concentrations are high.
T
Allosteric inhibition prevents transcription of genes
F
The operator region of an operon is where repressor proteins bind.
T
E. coli (and other bacteria) use only positive or negative control of transcription alone; never both together to regulate expression of an operon.
F
E. Coli will run (not tumble) continuously when no food (and no repellant) is present.
F
Joshua Lederberg discovered the F plasmid
F
It was Esther L.
Which of the following modes of DNA transfer does not require homologous recombination?
Transduction
Transformation
Transposition
Conjugation
Transposition
The notation uvrB– indicates
The bacteria has a wild type copy of this gene.
The wild type product of this gene.
The bacteria has a mutated copy of this gene.
The mutated product of this gene.
The bacteria has a mutated copy of this gene.
You would have to screen for a mutant bacterial strain that has acquired antibiotic resistance (relative to its wild type
F
A plasmid vector can hold a larger DNA insert of interest than a cosmid vector
F
Although present in many vectors, the origin of replication (oriV) is not essential to plasmid replication.
F
A desirable property for a good cloning vector is:
a piece of DNA that is able to replicate autonomously within a bacterial cell.
a piece of DNA that has been well characterized including known restriction sites.
a piece of DNA that includes easily detectable marker genes.
All of these choices.
All of these choices.
A disinfectant is a chemical that kills infectious microbes and is safe enough to be used on tissues such as human skin.
F
Alcohol works as a disinfectant by
denaturing proteins.
denaturing nucleic acids.
dissolving and disrupting cell membranes.
disrupting carbohydrate function
dissolving and disrupting cell membranes.
Transduction, conjugation, and transposition refer to:
Methods of reproduction/ binary fission
Different mechanisms of gene expression
Methods of DNA synthesis
Modes of genetic transfer between/within bacteria
Modes of genetic transfer between/within bacteria
LacZ refers to both gene encoding for beta galactosidase and a protein.
F
An auxotroph lacks the ability to make some compound that is essential for growth.
T
A wild type strain has mutated in some way (i.e. ‘gone wild’).
F
Nutrient broth is composed of beef extract and peptone. As a result, nutrient broth is considered a:
defined medium because the ingredients are known.
defined medium because the exact chemical composition of beef extract and peptone is known.
complex medium because it contains more than one ingredient.
complex medium because the chemical compositions of beef extract and peptone are not precisely known.
complex medium because the chemical compositions of beef extract and peptone are not precisely known.
The large intestine is likely inhabited by
obligate aerobes.
aerobes.
facultative anaerobes.
all of these choices.
facultative anaerobes.
A broth culture was diluted 10-fold, 0.1 ml was spread onto an agar plate and 47 colonies were counted. What is the estimated cell concentration in the original broth culture?
4,700 cells/ml
You determine that generation time in your bacterial culture is constant. In which phase is your culture?
Log/exponential phase
You are growing an E. coli culture in the lab and want to measure the number of viable cells over time. Which method could you use?
Streak plate
Spread plate
Direct count
All of the above
All of the above
You are growing an E. coli culture in the lab and want to measure the number of viable cells over time very quickly (by tomorrow AM). Which method could you use ?
Streak plate
Spread plate
Direct count
Spectrophotometer
Spectrophotometer
A chemolithoautotroph gets its electrons/energy from reduced minerals and its carbon from CO2.
T
A microaerophilic microorganism is exceptionally small (relative to other microbes) and uses atmospheric levels of O2 as a terminal electron acceptor.
F
Microbes from which environment might be most likely to degrade agar?
Lake water
Marine water
Human large intestine
Soil
Marine water
