Exam 5 Flashcards
Transferring electrons between proteins in the mitochondrial membrane is a type of ______________
Redox reaction
Pathogenic staphylococci can be differentiated by plating on blood agar plates. What allows you to tell them apart?
The extent of hemolysis
Which of the following might a pathogen use to attach to host cells?
pili or fimbriae
Ocean viruses contribute to carbon cycling by _________ ocean bacteria and algae
lysing
Which of the following ‘fix’ carbon and increase biomass?
a corn field
_____ phage genes code for protein that take over host functions. _____ phage genes include structure components of the virus
Early, late
a community of bacteria which coordinate their activities to colonize a surface is called
biofilm
lactose intolerance in humans is due to the lack of an _____ necessary to split a _____
Enzyme, disaccharide
True or False: vaccination was invented by a British doctor in 18th century London
False
A streak plate is used to isolate single colonies from a mixture of bacteria. The equivalent technique when working with viruses is called
Plaque assay
True or false: living genetically modified humans walk the Earth
True
all of the following are natural polymers except: cellulose, glucose, chitin, glycogen
Glucose
True or false: most bacteria from environmental samples can be cultured in a lab
False
True or false: animal viruses are capable of lysogeny
True
All life can be sorted into three domains. The best evidence of this comes from
rRNA sequence analysis
which of the following is an emerging disease in our area: influenza, malaria, lyme
No correct answer
according to our present understanding, mitochondiral and chloroplasts are of _____ origin
bacterial
In bacteria and mitochondria, a concentration of protons builds on one side of a _____. These protons can only travel through a channel in a protein called an _____, which functions as a “turbine” to make _____
Membrane, ATPase, ATP
You have streaked to single colonies, a sample from a dead animal. The results show several different types of colonies. This result indicated a _____ and _________ clearly indicate a cause of the animal’s death
Mixed population, does not
True or false: smallpox has killed hundred of millions of people since there have been humans
True
True or false: Smallpox infections no longer occur on earth due to vaccination
True
True or false: endospore production is a bacterial response to rapid environmental change
True
recent increases in Whooping cough are due to: anti-vaxxers, weakened vaccine immunity, changes in the bacteria
All of the above
True or false: enveloped viruses code for their own envelope
False
True or false: You were doing a Gram staining and forgot to counter stain with safranin. This would prevent you from identifying a gram positive bacteria.
False
One reason there are far fewer antiviral drugs is _________
Viruses use host processes to multiply
Cellular respiration requires ___________ which is used to collect/neutralize _____________ in the mitochondria
oxygen, electrons
Human pathogenic bacteria are ___________
mesophiles
Gram negative bacteria have an outer membrane, a portion of which is toxic to humans and causes fever. This molecule is made of _____
sugar and lipid
True or false: ATP synthase ‘run backwards’ and will consume ATP
True
Magnetosomes are _____ structures used by some bacteria to _____
Iron, escape oxygen
The Calvin cycle is the process which plants use to _____ and _____
Fix CO2, build biomass
Suppose you treat an exponentially growing culture of bacteria with a potential antimicrobial compound. Over the next few hours, cell doubling stops (untreated, control culture continues doubling) but the cells remain metabolically active. This antimicrobial compound is _____
Bacteriostatic
Minimum inhibitory concentration (MIC) refers to minimum _____
amount of a chemical required to kill all the microorganisms
Electrons captured from the breaking of glucose in the cytoplasm of eukaryotic cells are carried to the _____ by _____.
Mitochondria, NADH
True or false: Persistent HPV infection requires viral integration in superficial/surface epithelia layers
False
Where in a liquid culture would you find an anaerobic bacterium?
at the bottom of the tube
Hydrothermal vent tube worms contain _____ bacteria (symbiotes), which in turn obtain _____ from the worms’ blood stream
chemolithotrophic, oxygen
Pasteurization is now a common procedure to ensure food safety. Pasteur’s flasks disproved _____
‘bad’ air causes diseases
What microorganisms use inorganic compounds like hydrogen sulfide as their energy source
Chemolithotrophs
This protein is made by bacteriophage and humans
lysozyme
Lysogenic bacteria exposed to UV light will: accumulate DNA damage, die, accumulate maturing bacteriophage
all are correct
Glycolysis is a series of _____ leading to _____ molecules
Enzymatic reactions, three carbon
True or false: Tamiflu prevents influenza virus from binding to host cells
False
These microorganisms use light as their energy source
Phototrophs
The terms “run” and “tumble” are used to describe _____
Movement of bacteria
True or false: water is a waste product of cellular respiration
True
Robert Koch is best known for a set of rules he created, now commonly known as Koch’s postulates. What is the purpose of Koch’s postulates
They help to determine if a particular infectious agent causes a specific disease
Three options by which an organism may obtain energy are: light, organic molecules and _____
inorganic molecules
Sugars are used by living systems for
energy storage and building materials
True or false: enveloped viruses contain genes for their own plasma membrane
False
True or false: horizontal/lateral gene transfer is largely responsible for human genetic diversity
False
True or false: some bacteria owe their virulence to a viral prophage integration
True
sRNAs (short RNAs), viroids, and CRISPR all work by a similar mechanism. They all rely on _________ to destroy or change a target sequence
base pairing
True or false: The sum total of an organism or cell’s protein content is termed its genome
False
True or false: the sum total of the information stored in a cell or organism’s DNA is called its proteome
False
Colistin is a charged antibiotic molecule that can cause kidney damage. Some colistin resistance has been shown to?
change the charge on the cell surface
True or false: some viral prophage are able to measure the number of host cells outside the individual cell they are in
True
Which of the following methods of gene transfer has the potential to transfer more unique regions of the bacterial chromosome?
Generalized transduction
The ‘transforming factor’ in Griffith’s (blue/red bacteria, mouse dead/live) experiment was ultimately found to be a gene for?
a sugar coat
In the experiment that established that DNA replication occurs semi-conservatively, newly synthesized strands could be distinguished from parental strands by?
Density
Some bacteriophage use a protein called Tip to control entry into the lytic cycle. Qtip expression is regulated through a protein that is a _____________
transcription factor and receptor
Plasmids that govern their own transfer are known as _____
Conjugative
When testing antibiotic resistance using “paper disc test”, you find the clearing around the disc is larger in the presence of EDTA. You conclude the bacteria is _____.
Using a metalloprotease to inactivate the antibiotic
Some bacteria use pili to capture _______ from the environment. Expression of pili genes and membrane pore complex genes are linked to ________?
DNA, available food sources
The Penicillin family of antibiotics bind to the active site of _____
Enzymes that form peptide crosslinks
When _____ interacts with RNA polymerase, it increases the rate of transcription initiation of the lac operon
cAMP/cAMP response protein (CRP)
Cipro is a _____ antibiotic. This is because it _____.
Broad spectrum, prevents DNA unwinding
Gene X makes a protein that binds to DNA. A mutation of gene X causes an increase in the expression of gene Y. We can conclude that _____
Gene X is a negative regulator of gene Y
A b-lactamase/penicillinase provides resistance to penicillin by _____.
modifying the penicillin-binding protein involved in cell wall synthesis and destroying the ring structure of penicillin
The acronym ORF stands for _____
Open reading frame
To be activated a quorum-sensing gene system requires the accumulation of a secreted small molecule called an _____
Auto inducer
True or false: a phage particle can be infectious even if all its DNA has been replaced by bacterial DNA
True
Operons _____.
Allow coordinated expression of multiple related genes in prokaryotes
Bacterial heat shock response requires expression of many proteins including _____, which prevent misfolding/denaturation. Coordinate expression of these different genes is controlled by _____
Chaperons, a unique sigma factor
Competence refers to the ability of bacterial population to _____
Be transformed by foreign DNA
True or false: In prokaryotes all RNA contains coded information for amino acid sequence
False
Insertion sequences are the simplest mobile genetic element. They code for a single protein. What does this protein do?
It can cut & reseal DNA strands
What do exposure to Cipro, Covid-19, and the Lyme’s disease bacteria have in common?
All are associated with post treatment disease/ symptoms
The promoter site of an operon is the site at which _____ initiates
RNA polymerase
In a gel-shift assay, free DNA runs _____ than protein::DNA complexes
Faster
In the absence of lactose, the lac _____ will _____
operator, be bound by repressor
Two populations of bacteria have recently acquired resistance to Mitchomycin. Population 1 did so in three generations (60 minutes). Population 2 acquired this resistance over the course of several months. The most likely mechanism for resistance in Population 1 is?
Horizontal gene transfer of a plasmid
Which of the following would cause a stringent response in a bacterial population: antibiotic treatment, rapid change in available nutrients, rapid increase in temperature
All are correct
True or false: heat maps are a way of representing changes in gene expression
True
The first enzyme in a metabolic pathway has a second binding pocket for a product many steps down the metabolic pathway. This is likely an example of _____
Allosteric regulation
You have cloned the promoter from your favorite retinal gene upstream (in front of) GFP (green fluorescent protein) and then made a transgenic fish. What would you expect to see when the fish grow up?
Only the eyes of the fish glow green
Certain bacteria, when under stress produce transducing particle-like gene transfer agents (GTAs). These particles contain _____ pieces of bacterial DNA and the portion of the population that produces GTAs is determined _____.
Random, stochastically
Calico cats have three colors of fur. This is due to inactivation of _____ and ultimately is controlled by _____.
One X chromosome, a guide RNA
CRISPR (clustered regularly interspaced short palindromic repeats) is: a bacterial defense mechanism, used to edit many different genomes, a type of immunological memory
All are correct
What are sigma factors responsible for?
Binding of RNA polymerase to promoter sequences
Which of the following are quorum-sensing phenomena: squid light organ, gut enterotoxin release, competence/transformability
All are correct
Adding the amino acid Arginine to a bacterial culture _____
Represses the synthesis of the enzymes required for the production of arginine
What do Texiobactin and Vancomycin have in common?
Both are relatively resistance proof and both inhibit the linking of cell wall to plasma membrane
True or false: RNA sequencing does not sequence RNA directly
True
True or false: RNA sequencing is a method for genomic analysis
False
Prokaryotic genes as an _____ are transcribed as _____
Operon, a polycistron
“Gene chips” contain ____________ for a large set of genes. ___________ are fluorescently labeled and are hybridized to the chip to measure changes in ______________?
single-strand DNAs, mRNAs, gene expression
A DNA/genomic mutation removes the RBS from the 5’ UTR (untranslated region) of your favorite gene. This gene would be?
transcribed but not translated
HIV has an RNA genome and can persist in human cells as a lysogen. What is the first step in this process?
Converting RNA to DNA
Purposely infecting bacteria with Transposons is a type of ____________
mutational screen
Which of the following does not lead to more antibiotic resistance bacteria: antibiotics in animal feed, false positive Strep throat (antibody) tests, over prescription, taking the entire prescription
Taking the entire prescription
DNA replication happens in a ___________ manner, using information from the _______ strand as _________ to synthesize the new strand
semi conservative, parental, template
What do BCG treatmeant, halo nevi, and spontaneous remission have in common?
All suggest a role for the immune system in fighting cancer
True or false: Colonic epithelial cells get most of their energy from the blood stream
False
Coagulase is a _____ protein used to _____
bacterial, escape immune detection
Certain types of E coli produce a chemical mutagen called Colibactin. Studies have shown that it causes mutations consistent with _____ in humans.
Colon cancer
Neutrophil expressed traps (NETS) are made of?
DNA
True or false: live virus can be used to vaccinate against influenza
True
Cholera toxin is?
an enterotoxin
True or false: Mast cells have receptors for an antibody variable region
False
True or false: There is an antibody for every allergen
True
HIV specifically attacks and kills helper T cells. This drastically weakens the immune system because helper T cells _____
Stimulate antibody & cytotoxic T cell production
Activation of a naive cytotoxic T cell (Tc) requires engagement of a co-receptor pair CD28/B7. Antigen Presenting Cells and cytotoxic T cells are originally brought together by _____
MHC, TCR, & antigen
True or false: there is a single antibody gene for every antigen your body will ever encounter
False
True or false: the Tuberculosis skin test is a type of immediate inflammatory response
False
True or false: a ring that causes a rash in your finger involves Mast cell activation
True
The ability to make antibody quickly after a second exposure to antigen is ultimately due to _____
Memory cells
Antibodies present in a newborn are considered _____
Naturally acquired passive immunity
Thymic education refers to the process by which _____ are selected for their ability to recognize _____ properly
T cells, foreign antigen
The inflammatory response includes spiking a fever. This is done by the release of a _____ which travels to the _____
cytokine, brain
After activation, B cell receptors (BCR) become _____
Antibodies
The Limulus (horseshoe crab) amebocyte lysate assay can be used to detect _____ in intravenous solutions
Endotoxin
Bacteria that are phagocytosed are destroyed in the _____ by a combination of enzymes and _____.
Lysosome, reactive oxygen species
One type of interferon is expressed when _____ is detected in a cell. Its absorption into neighboring cells prepares them to _____
double stranded RNA, commit suicide
True or false: In humans, specific bacterial infections have been treated successfully with fecal transplants
True
Akkermansia munciphilia is a human gut bacteria that metabolizes _____
Mucus
Certain types of E coli can cause bloody diarrhea. Which type of toxin do they use to accomplish this?
Endotoxin
Botulinum toxin is a _____ which prevents _____ at neuromuscular junctions
neurotoxin, vesicle fusion
GALT is part of the ________ which is responsible for defending against and _______ pathogens from outside the body
lymphatic system, sampling
The following foreign antigens would be detected by the innate immune system except: viral RNA, 2025 influenza proteins, proteoglycan, flagellin
2025 influenza proteins
Studies using a mouse model of autism have shown which of the following can lessen the autistic behavior: antibiotics in their water, a single species of bacteria in their water, a bacterial metabolite in their water
A single species of bacteria & a bacterial metabolite in their water
Identify the component that is not part of innate immune defenses: skin, cytotoxic T cells, toll-like receptors, mucus
Cytotoxic T cells
Cholera toxin causes diarrhea by _____ colonic endothelial cells
Increasing the flow of ions out of
The human microbiome contains all _____
Organisms present in & on the body
True or false: bacterial adhesions refer to a species-specific interaction between the pathogen and molecules on the host cell surface
True
True or false: fermented foods and yogurt are good sources of prebiotics
False
Which of the following can be used as a diagnostic test for a suspected infection: florescent antibody staining, selective culture media, agglutination
All are correct
Why are Western blots used to confirm rapid diagnostic tests (HIV & others)
They produce a more complex banding pattern
True or false: Chimeric Antigen Receptor T cell therapy (CART) does not always work. Antigen-positive relapse means the cancer antigen has mutated
False
The complement system is considered part of the ______ immune system because it is activated by _________
Innate, any bacteria
True or false: Type O blood reacts with anti-Type B antibodies in serologic agglutination tests
False
PDL1, immune checkpoint inhibitor therapy is an _______ based treatment which can ______ the number of T cells attacking a tumor
antibody, increase
Opsonins _____________
Increase phagocytosis
Irritable Bowl Disease (IBD) is an overreaction of the immune system to ____________
gut microbiota
Activation of complement leads to which of the following: increased inflammation, increased phagocytosis, holes in the bacterial membrane
All are correct
Natural killer cells ______________
Kill cells that lack MHC molecules
Severe Combined Immunodeficiency Disease (SCID) is a genetic condition which: affects antibody production, results in a lack of Natural Killer T cells, affects T cell production
Affects antibody production & affects T cell production
True or false: pathogens with heavily glycosylated outer membranes cannot activate complement
False
The variable region of an antibody is _________. The constant region signals _________ by changing shape.
A region for binding antigen, antigen is bound
The control line in a rapid test tells you ____________
You have added enough sample
Major histocompatibility complex proteins are types in organ transplant cases. They are: markers of self, viral antigens, ‘presenter’ molecules/antigen holders
Markers of self and presenter molecules
The ‘older’, _________ portion of the human immune system includes receptors that detect double-stranded RNA. The ________ makes specific tools (antibodies/T cells) to fight specific pathogens/infections
Innate, adaptive
True or false: wounds that release pus are a sign that the bacteria is able to kill white blood cells
True
True or false: Swelling is caused by the release of solutes by the bacteria that increase osmotic pressure
False
True or false: ‘Cytokine storms’ can be caused by certain bacterial infections and/or cancer treatment
True
Small mutations in the genes for the H and N proteins (hemagglutinin and neuraminidase) lead to changes in the infectivity of the influenza virus. This is also known as
genetic DRIFT
True or false: Smallpox is an endemic disease in parts of Africa
False
Identify the acute infection: HIV, HPV, Norovirus, Lyme’s (Burgdorferi)
Norovirus
True or false: for any disease prevalence will be less than incidence
False
The onset of an epidemic began with a sharp rise in the number of cases reported over a few days. This indicates that the mode of transmission is?
a common source
The two leading Covid vaccines both contain ________ “packaged” in ___________
mRNA, lipid
A disease that is present in unusually high numbers throughout the world is called a __________
pandemic
Which of the following is an emerging disease in New England: influenza, cholera, West Nile virus
West Nile virus
HIV is a _________ with a _________ genome. An enzyme called ________ copies its genome into ________ which is then integrated into the infected cell’s DNA
retrovirus, RNA, reverse transcriptase, DNA
True or false: the majority of sexually active people will be exposed to HPV
True
True or false: HPV infections led to cancer when the virus integrates into superficial epithelial cells
False
Paxlovid is a protease inhibitor, its mechanism of action is similar to certain HIV treatments. The effect of these drugs is?
prevent viral maturation
True or false: man has created synthetic DNA
True
True or false: Synthetic DNA molecules have escaped into the environment
True
What was the breakthrough advancement that led to the success of mRNA vaccines?
advances in backbone stability
The Flu vaccine is not always effective in preventing severe disease. This can be due to?
Variants that arise after production starts
Whooping cough outbreaks across the country have been associated with non-medical exemptions. Another factor that has been associated with increased whooping cough incidence is ___________
acellular vaccines
A certain bacterium has as its reservoir a rodent only found in the Southwest United States. Each year, a few human cases of the disease caused by this bacterium are reported in Arizona and New Mexico. This disease can be categorized as _____________
endemic
True or false: Some tick bites have been shown to cause a delayed allergic reaction to a mammalian carbohydrate
True
Identify the viral infection that is transmitted by aerosol droplets: influenza, HPV, West Nile virus, Lyme disease
Influenza
Heart disease and cancer are the leading cause of death worldwide in the 21st century. Up until the mid-twentieth century, the top three causes of death were all due to?
infectious diseases
The main habitat (reservoir) of Clostridium tetani, the causative agent of tetanus, is?
soil
Typhus and Rocky Mountain Spotted Fever are both caused by __________
bacterial parasites
The original Whooping cough vaccine used in the US was more effective than the one currently being used. Which of the following explains why: original vaccine was a subunit vaccine, current vaccine is whole agent vaccine, original vaccine induced more memory cells
original vaccine induced more memory cells
True or false: over 300,000 people die every year worldwide due to under-treated Strep throat
True
True or false: PreP is a form of antiretroviral treatment for HIV infection, that when taken daily, reduces viral load to the point where the person cannot transmit the virus
True
Novel Chicken Virus 7 has a high mortality rate (~80%). What kind of evidence would be the most concerning in terms of pandemic risk?
Poultry worker family deaths
True or false: HPV vaccination can still be effective after having sex
True
True or false: cancer progression requires prophage integration into a stem cell
True
True or false: a test for anti-Covid-19 antibodies on the day of infection would be negative
True
When herd immunity against a particular pathogen has been reached in a population, _______ people are protected
all
True or false: infectious diseases are the cause of about 15% of all deaths worldwide
True
Which of the following are established reservoirs for Influenza: domesticated turkeys, wild turkeys, pigs
all are correct
True or false: vaccines are available for all sexually transmitted diseases
False
True or false: if not treated completely with antibiotics, Group A Streptococci can cause severe post-infection diseases
True
True or false: vaccination is a type of artificial passive immunization
False
SARS-COVID-19 has become an endemic disease worldwide. Which of the following is the best evidence for this fact
large “waves” of new infections are absent
What accounts for the chance of genetic shift leading to the next flu pandemic?
it has a segmented genome
True or false: upper respiratory tract pathogens are generally more deadly than lower respiratory pathogens
False
PLWH (people living with HIV) are at greater risk for _____________ than the average population
opportunistic infections
True or false: in the US ~15,000 liver cancer deaths caused by chronic Hepatitis Virus C (‘HepC’) occur each year
True
True or false: HepC treatment can cost $25,000-95,000 USD even with insurance
True
The ‘a’ in DTaP vaccine refers to?
the type of vaccine
What do treatment for Covid with Paxlovid and certain types of HIV ART have in common
Both inhibit the viral protease
Why are most domesticated turkeys recently being raised indoors
To prevent viral infection
True or false: During the Phase III trials for the Covid mRNA vaccine, the majority of side effects were reported in the vaccine arm of the trial
False
AIDs patients world-wide ultimately die from __________
secondary infections
