Final exam Flashcards
(297 cards)
1
Q
Which of the following refers to the type of interaction between two prokaryotic populations in which one population benefits and the other is not affected?
A
commensalism
2
Q
Which of the following statements about Neisseria is false?
A
They are strictly aerobic.
3
Q
Spirochetes cause the following diseases except for:
A
Chlamydia
4
Q
Match each bacterial genus with the best description of its morphology.
A
Clostridium gram positive rods
Streptococcus chains or pairs of cocci
Staphylococcus clusters of cocci
5
Q
The envelope of a virus is derived from the host’s:
A
membrane structures
6
Q
What is an example of a chronic infection?
A
HIV
7
Q
Match the events that are specific for lytic cycle, lysogenic cycle, or both.
A
Active synthesis of phage DNA and proteins lytic cycle
Phage attaches to the host cell (attachment) both
New phages released, killing host cell lytic cycle
Phage DNA incorporated into the host genome lysogenic
Phage DNA injected into host cell (penetration) both
New phage particles assembled lytic cycle
8
Q
Which of the following are signs of an animal cell infected by a virus? Check all that apply.
A
vacuoles in the cytoplasm
inclusion body in the cytoplasm
changes in cell shape
9
Q
aa
A
aa
10
Q
What is the theoretical maximum number of ATP molecules that are produced by aerobic respiration if glucose is the energy source?
A
38
11
Q
Which of the following statements about fermentation is TRUE?
A
Microbes can be differentiated according to the substrates they are able to or unable to ferment.
12
Q
During which phase would penicillin, an antibiotic that inhibits cell-wall synthesis, be most effective?
A
log phase
13
Q
While ____ is able to detoxify a reactive oxygen species, it also produces one, hydrogen peroxide.
A
Superoxide dismutase
14
Q
Bacteria isolated from Lake Natron, where the water pH is close to 10, are which of the following?
A
alkaliphiles
15
Q
A soup container was forgotten in the refrigerator and shows contamination. The contaminants are probably which of the following?
A
Psychrotrophs
16
Q
Bacteria living in salt marshes are most likely which of the following?
A
Halotolerant
17
Q
Cells are always producing proteins from every gene they possess.
A
False
18
Q
Which of the following enzymes involved in DNA replication is unique to eukaryotes?
A
telomerase
19
Q
What are the three different regions of a gene?
A
Promoter, coding region, and terminator
20
Q
Each codon within the genetic code encodes a different amino acid.
A
False
21
Q
Which of the following is an example of a frameshift mutation?
A
deletion of one nucleotide
22
Q
Malaria is caused by a:
A
Protozoan
23
Q
E. coli serotype O157:H7 infection may cause severe life-threatening symptoms such as hemorrhagic colitis. Most of the symptoms arise due to the Shiga like toxin, which has a genetic similarity with Shiga toxin of Shigella dysenteriae. Why do scientists think that the Origin of the Shiga toxin gene is from Shigella species that cause dysentery, a disease with a similar symptom?
A
Because both genera are evolutionarily related, and the same bacteriophage can transduce pieces of DNA between the species.
24
Q
What is an example of an activator of a repressor protein?
A
tryptophan
25
Which of the following scenarios was created through genetic engineering?
The gene that codes for insulin production was inserted into a bacterium and then the bacterium is used to produce insulin.
26
Which of the following techniques is used to visualize DNA?
Southern blot
27
Which of the following is the best definition of gene therapy?
The introduction of a non-mutated and functional gene into a patient's DNA.
S. aureus skin infections usually happens when skin is broken, causing raised, red bumps localized around the hair follicles. These bumps are usually pus-filled, or purulent.
SSSS mostly affects newborns and babies, in which exotoxins cause blisters and large scale skin peeling.
Impetigo is a highly contagious condition common in children, in which exotoxins cause peeling skin, crusty and flaky scabs around the mouth, face and extremities.
28
To prevent transmission, a person with an active MRSA infection should:
Keep the lesion covered
29
Nerve cells form long projections called ________.
axons
30
Order the following structures from the outside (close to the skull) to the inside (close to the brain).
skull
Dura mater
Arachnoid mater
subarachnoid mater
Pia matter
Brain
31
Rabies is one of the few diseases that can be treated with both passive and active immunizations. Why is that?
The slow spread of the virus in the peripheral allows time for the patient's immune system to be activated.
The rabies virus is a(n) enveloped RNA virus. After infection, the virus replicates slowly in the peripheral, and rapidly in the CNS.
32
Who should be getting the meningitis vaccination? Check all that apply.
young people serving in military
travelers visiting the 'meningitis belt'
young people living in dorms
16 year old for booster
11-12 year old children
33
N. meningitidis can only grow on chocolate agar and not on regular nutrient agar. What does this mean about its nutritional requirements? Check all that apply.
It needs additional nutrients for growth
It is fastidious
Which of the following are potential reasons why the prevalence of N. meningitidis infections is high in the 'meningitis belt'? Check all that apply.
These SSA countries have overcrowding and low standards of living
Citizens in these SSA countries may suffer malnutrition
Citizens in these SSA countries may have low immunocompetence
These SSA countries have dry, dusty climate
34
What types of microbes live in the intestines?
Diverse species of bacteria, archaea, and fungi, especially Bacteroides and Firmicutes bacteria
35
The absence of Listeria 16S rRNA detected from the amniotic fluid culture means that the fetus is not infected with Listeria.
True
36
It is common for Listeria to be antibiotics-resistant.
False
37
What does the acronym "PPE" stand for?
Personal Protective Equipment
38
Match the description with each biosafety level.
BSL-1 Microbes are not known to cause disease in healthy hosts and pose minimal risks to workers and the environment.
BSL-2 microbes are typically indigenous and and are associated with diseases of varying severity. They pose moderate risk to workers and the environment.
BSL-3 microbes are indigenous or exotic and cause serious or potentially lethal diseases through respiratory transmission
BSL-4 microbes are dangerous and exotic, posing a high risk of aerosol-transmitted infections, which are frequently fatal without treatment or vaccines. Few labs are at this level
39
What are the advantages of pasteurizing foods and beverages? Mark all correct answers.
to increase the shelf life of a food or beverage
to kill pathogenic microbes
40
Which of the following terms is used to describe the time required to kill all of the microbes within a sample at a given temperature?
thermal death time
41
Which chemical disinfectant works by methylating enzymes and nucleic acids and is known for being toxic and carcinogenic?
formaldehyde
42
Which of the following peroxygens is widely used as a household disinfectant, is inexpensive, and breaks down into water and oxygen gas?
hydrogen peroxide
43
A scientist discovers that a soil bacterium he has been studying produces an antimicrobial that kills gram-negative bacteria. She isolates and purifies the antimicrobial compound, then chemically converts a chemical side chain to a hydroxyl group. When she tests the antimicrobial properties of this new version, she finds that this antimicrobial drug can now also kill gram-positive bacteria. The new antimicrobial drug with broad-spectrum activity is considered to be which of the following?
semisynthetic
44
Which of the following combinations would most likely contribute to the development of a superinfection?
long-term use of broad-spectrum antimicrobials
45
Which of the following does not bind to the 50S ribosomal subunit?
tetracyclines
46
One of the choices below is true for all of the following: penicillins, cephalosporins, monobactam, and carbapenems.
Is the presence of Beta lactam ring
47
Which of the following is not an appropriate target for antifungal drugs?
cholesterol
48
Which of the following is an appropriate target for antifungal drugs?
(1→3) glucan
ergosterol
chitin
49
Which of the following is a target for an antifungal drug? Check all that apply.
Cell membrane
Chitin synthesis
Ergosterol synthesis
Mitochondria (ETC)
50
MRSA (Methicillin Resistant Staphylococcus Aureus), develops resistance to Methicillin (low affinity PBP) through this process.
Target modification
51
Which of the following types of drug-resistant bacteria do not typically persist in individuals as a member of their intestinal microbiota?
MRSA
52
What are some factors that determine the size of a zone of inhibition in Kirby-Bauer disk diffusion test? Check all that apply.
drug solubility
the nature of the bacteria
the thickness of the agar medium
53
What is an example of a chronic disease?
Hepatitis B
54
Which of the following would be a sign of an infection?
fever
55
What are Koch's postulates used for?
To determine the cause of a new disease
56
Pathogen A has an ID50 of 50 particles, pathogen B has an ID50 of 1,000 particles, and pathogen C has an ID50 of 1 × 106 particles. Which pathogen is most virulent?
pathogen A
57
What is the excessive number of bacterial toxins in the blood known as?
toxemia
58
What is excessive activation of the immune system and severe response that can lead to life threatening fever, inflammation, and shock, are caused by?
Superantigens
59
Match the concept with its correct definition:
Sporadic diseases that are seen only occasionally, and usually without geographic concentration
Epidemic diseases for which a larger than expected number of cases occur in a short time within a geographical region
Endemic diseases that are constantly present (often at a low level) in a population within a geographical region
Pandemic and epidemic that occurs on a world wide scale
60
The way that COVID-19 is spreading is called:
propagated spread
61
A disease that has a steady frequency over time in a particular geographic location is
endemic
62
A blanket from a child with chickenpox is likely to be contaminated with the virus that causes chickenpox (Varicella-zoster virus). What is the blanket called?
Fomite
63
When hiking in Northern California around the Russian River, Mary was bitten by a tick. The tick transmitted the bacteria Borrelia burgdorferi to Mary’s leg tissues while it was obtaining a blood meal. This bacteria is found in certain species of hard-bodied ticks around the USA such as the Deer Tick. The Borrelia bacteria completes part of its life cycle in the ticks.
Because the bacteria completes part of its life cycle in the tick, the tick is considered a _______ for the bacteria.
Biological vector
64
Why are emerging diseases with very few cases the focus of intense scrutiny?
They are increasing and therefore not controlled
65
Match the Lyme disease symptom to the stage of the disease.
Bull’s eye (erythema migrans) early localized stage
Facial paralysis early disseminated stage
Meningitis late stage
66
Which of the following is true of Borrelia burgdorferi (Lyme disease)? Check all that apply.
it has internal flagella
It is gram-negative
It is a spirochete
67
Which of the following represents a difficulty of diagnosing Lyme disease? Check all that apply.
Many symptoms resemble those of other diseases
Only 70-80% patients develop the bull’s eye rash
68
Which of the following is not a characteristic of the normal biota of the female reproductive tract during childbearing years?
Vaginal pH is neutral
69
Match the following virulence factors of K. pneumoniae with their function.
Capsule avoid phagocytosis
LPS cause systemic symptoms such as fever
fimbrial adhesins attachment to host cells
Siderophores sequester iron for survival
70
Why would a urine culture be informative in diagnosing UTI? Check all that apply.
The lack of growth of bacteria or fungi could indicate a viral infection.
The lack of growth of bacteria or fungi could indicate other conditions such as cancer.
The growth of bacteria would confirm a bacterial caused UTI.
The growth of fungi would confirm a yeast infection.
71
What is the mortality rate of the 2013 bird flu (H7N9) epidemic?
33%
72
Which of the following is a component of the influenza virus? Check all that apply.
Neuraminidase (N) spike
M2 ion channel
Capsid proteins
73
Match the H and N spikes with the steps they are involved in.
Involved in attachment H spike
Involved in release N spike
Cleaves sialic acid receptors to make a clean exit N spike
Binds sialic acid receptor to facilitate entry H spike
74
Which of the following make up feces? Check all that apply.
Undigested food
Epithelial cells
Mucus
Microbes
75
The part of the gastrointestinal tract with the largest natural microbiota is the:
Large intestine or colon
76
Why does the CDC think that the 1 million cases of salmonellosis per year is an underestimate? Check all that apply.
Because most infections are mild and self-limiting
Because many patients do not seek medical help
77
Which of the following is not a criteria for determining the Biosafety Level of a particular microbe?
whether it is gram positive or gram negative
78
Match the controlling microbial growth term with the correct definition.
Disinfection reduces or destroys microbial load of an inanimate item through application of heat or antimicrobial chemicals
Sterilization completely eliminated all vegetative cells, endospores, and viruses from an inanimate item
Antisepsis reduces microbial load on skin or tissue through application of an antimicrobial chemical
Degerming reduces microbial load on skin or tissue through gentle or firm scrubbing and use of mild chemicals
79
When flaming the loop in the lab this is an example of __.
dry-heat sterilization
80
Which of the following microbial control methods does not actually kill microbes or inhibit their growth but instead removes them physically from samples?
filtration
81
Soaps are classified as disinfectants.
False
82
Which of the following best describes the mechanism of action iodophor?
oxidizes cellular material
83
Bacteriostatic ______________________________________.
Causes a reversible inhibition of growth of the target bacteria
84
One of the bacteria that is notorious of causing superinfection is:
Clostridium difficile
85
Which one is the antimicrobic that does not inhibit the cell wall synthesis?
Gentamicin
86
Which of the following antimicrobials inhibits the activity of DNA gyrase?
Ciprofloxacin
87
Which of the following is not an appropriate target for antifungal drugs?
cholesterol
88
There are fewer drugs (Antifungal, antiprotozoan, antihelminthic) available to treat other microbes than bacteria, because____________________________.
They are so similar to human cells that selective toxicity is difficult to achieve
89
Which of the following resistance mechanisms describes the function of β-lactamase?
drug inactivation
90
Why have the United States and Europe banned the use of human antibiotics in animal feed?
Because it has been connected to drug resistant problem
91
What are some reasons why the development of new antibiotics has slowed down? Check all that apply.
developing new drugs is a lengthy process
developing new drugs is expensive
pharmaceutical companies can make more money developing drugs for chronic conditions
92
What is an example of a chronic disease?
Hepatitis B
93
During an oral surgery, the surgeon nicked the patient’s gum with a sharp instrument. This allowed Streptococcus, a bacterium normally present in the mouth, to gain access to the blood. As a result, the patient developed bacterial endocarditis (an infection of the heart). Which type of disease is this?
iatrogenic
94
The number of pathogen cells or particles required to cause active infection in 50% of inoculated animals is _______________________.
Median Infectious Dose (ID50)
95
Pathogen A has an ID50 of 50 particles, pathogen B has an ID50 of 1,000 particles, and pathogen C has an ID50 of 1 × 106 particles. Which pathogen is most virulent?
pathogen A
96
Order the following events when superantigen attacks.
1 superantigen stimulates immune cells
2 excess release of cytokines (cytokine storm
3 high fever and low blood pressure
4 multi-organ failure and death
97
Some of the following are membrane disrupting toxins. Mark all that apply.
Bacterial phospholipases
Leukocidins
Hemolysins
98
If I said there were 43,103 confirmed cases of the Novel Coronavirus worldwide on February 11, 2020, I would be talking about the ________________ of the disease.
Prevalence
99
Match each pioneer of epidemiology with his or her contribution.
John Snow determined the source of a cholera outbreak in london
Joseph Lister showed that surgical wound infection rates could be drastically reduced by using carbolic acid to disinfect the surgical tools, bandages, and surgical sites
Florence Nightingale compiled data on the cause of mortality in soldiers, leading to innovations in military medical care
Robert Koch developed a methodology conclusively determining the etiology of a disease
100
Match the term with its description.
common source spread there is a single source for all the individuals infected
point source spread the common source operates for a short time
continuous common source spread the commons source occurs for and extended time period
intermittent common source spread infection occurs, stop and begins again
101
Toxoplasmosis is caused by a protozoan parasite called Toxoplasma gondii. This parasite reaches sexual maturity in cats and the intermediate host is usually a rat or a bird. It can cause aberrant behavior in the prey organisms it infects, such as making the scent of cat urine appealing to rodents. Humans can become infected and affected by this eukaryotic single-celled organism, but the organism does not reproduce sexually in human tissues nor is it transmitted to other organisms by humans.
In this scenario, a human would be what to the Toxoplasma gondii organism?
Dead-end host
102
Toxoplasmosis is caused by a protozoan parasite called Toxoplasma gondii. This parasite reaches sexual maturity in cats and the intermediate host is usually a rat or a bird. It can cause aberrant behavior in the prey organisms it infects, such as making the scent of cat urine appealing to rodents. Humans can become infected and affected by this eukaryotic single-celled organism, but the organism does not reproduce sexually in human tissues nor is it transmitted to other organisms by humans.
In this scenario, a rodent would be what to the Toxoplasma gondii organism?
Intermediate host
103
Why are emerging diseases with very few cases the focus of intense scrutiny?
They are increasing and therefore not controlled
104
Which of the following is true of antigenic variation? Check all that apply.
Can evade immune detection
Renders antibodies ineffective
Plays a role in causing chronic disease
105
Match the tick stage with the host they feed on.
Larvae Mice
Nymphs Mice and humans
Adults deer, occasionally humans
106
Order the stages of the tick life cycle.
1 eggs
2 larvae
3 nymphs
4 adults
107
The following are conditions that can establish homeostasis due to the normal microbiota of the vagina. Mark all that apply.
Levels of estrogen
Production of lactic acid
Low pH
It is established shortly after birth
108
The urinary tract defenses in both males and females consists of mechanical factors such as ________, and chemicals like ________, to prevent the growth of pathogens in the system.
the flushing action of urine; lysozyme
109
Why would a urine culture be informative in diagnosing UTI? Check all that apply.
The lack of growth of bacteria or fungi could indicate a viral infection.
The growth of fungi would confirm a yeast infection.
The lack of growth of bacteria or fungi could indicate other conditions such as cancer.
The growth of bacteria would confirm a bacterial caused UTI.
110
What kind of bacterium is Klebsiella pneumoniae? Check all that apply.
Lactose fermenter
Capsule producing
111
Do you know how to tell the difference between a common cold and the flu?
mild fatigue common cold
severe fatigue flu
nasal congestion rare flu
nasal congestion common common cold
112
Compare and contrast the 2013 bird flu (H7N9) pandemic and the 1918-1919 flu (H1N1) pandemic.
Capable of person to person transmission 1918-19 pandemic
incapable of person to person transmission 2013 pandemic
Caused by re-assortment of RNA strands from different strains both
Caused by antigenic shift both
113
Arrange the steps of influenza viral life cycle in the correct order.
1 attachment
2 penetration (endocytosis)
3 uncoating
4 biosynthesis
5 assembly
6 release
114
Natural defenses of the GI tract include mechanical factors, such as peristalsis, and chemical factors, such as secretory IgA on the surface of the intestines.
True
115
The normal microbiota provides an additional barrier to infection via a variety of mechanisms. For example, these organisms outcompete potential pathogens for space and nutrients within the intestine. This is known as competitive exclusion. Members of the microbiota may also secrete protein toxins known as bacteriocins that are able to bind to specific receptors on the surface of susceptible bacteria.
Which of the following is used for salmonellosis diagnosis? Check all that apply.
Serological tests such as ELISA
Culture of bacteria
116
Which biosafety level is appropriate for research with microbes or infectious agents that pose moderate risk to laboratory workers and the community, and are typically indigenous?
BSL-2
117
Match the temperature with the following treatments.
Freezer -20 °C
Refrigeration 4 °C
Pasteurization 72 °C
Boiling 100 °C
Autoclave 121 °C
Dry oven 171 °C
118
Which of the following methods when used properly is capable of sterilization?
ionizing radiation
119
Which of the following is not a heavy metal disinfectant used to control growth of microbes?
chlorine
120
Which chemical disinfectant works by methylating enzymes and nucleic acids and is known for being toxic and carcinogenic?
formaldehyde
121
Bacteriostatic ______________________________________.
Causes a reversible inhibition of growth of the target bacteria
122
One of the bacteria that is notorious of causing superinfection is:
Clostridium difficile
123
Which one is the antimicrobic that does not inhibit the cell wall synthesis?
Gentamicin
124
Which of the following terms refers to the ability of an antimicrobial drug to harm the target microbe without harming the host? Check all that apply.
selective toxicity
therapeutic index
125
Distinguish the drugs treating influenza vs. HIV infections.
Inhibit neuraminidase influenza treatment
Inhibit reverse transcriptase HIV treatment
Inhibit protease HIV treatment
Inhibit integrase HIV treatment
Inhibit viral escape from endosome influenza treatment
126
Which of the following is a target for an antifungal drug? Check all that apply.
Chitin synthesis
Ergosterol synthesis
Mitochondria (ETC)
Cell membrane
127
Match the following drug resistance mechanism with its example.
Drug modification / inactivation beta-lactamase / penicillinase
Target modification modification of PBP active site
Prevention of cellular uptake or efflux reducing porin concentration on the outer membrane
Target mimicry TB bacteria producing a protein that mimics DNA structure
128
What are some of our practices that contribute to the rapid evolution of antibiotic resistance in bacteria? Check all that apply
over the counter access to antibiotics
overuse or misuse of antibiotics (prescribing antibiotics for cold or flu)
share antibiotics with family members
feeling better before the full course of antibiotics and stopping therapy early
129
Which of the following is one of the most common difficulties in finding new antibiotics?
Ability to grow new-found bacteria (microbes) in lab environment
130
What is a symptom?
Is a condition that is observed and experienced by the patient
131
A communicable disease that can be easily transmitted from person to person is which type of disease?
contagious
132
What are Koch's postulates used for?
To determine the cause of a new disease
133
A(n) __________ infection is a small region of infection from which a pathogen may move to another part of the body to establish a second infection.
Focal
134
What is excessive activation of the immune system and severe response that can lead to life threatening fever, inflammation, and shock, are caused by?
Superantigens
135
What is the excessive number of bacterial toxins in the blood known as?
Toxemia
136
The total number of deaths in a population due to a disease is the ________ rate.
mortality
137
Toxoplasmosis is caused by a protozoan parasite called Toxoplasma gondii. This parasite reaches sexual maturity in cats and the intermediate host is usually a rat or a bird. It can cause aberrant behavior in the prey organisms it infects, such as making the scent of cat urine appealing to rodents. Humans can become infected and affected by this eukaryotic single-celled organism, but the organism does not reproduce sexually in human tissues nor is it transmitted to other organisms by humans.
In this scenario, a rodent would be what to the Toxoplasma gondii organism?
Intermediate host
138
Cattle are allowed to pasture in a field that contains the farmhouse well, and the farmer’s family becomes ill with a gastrointestinal pathogen after drinking the water. What type of transmission of infectious agents would this be?
vehicle transmission
139
Which of the following factors can lead to reemergence of a disease?
A period of decline in vaccination rates
140
Lyme disease is transmitted by:
ticks
141
Which of the following is true of antigenic variation? Check all that apply.
Plays a role in causing chronic disease
Can evade immune detection
Renders antibodies ineffective
142
Why would a differential blood count be informative in distinguishing UTI from other conditions? Check all that apply.
An increased number of lymphocytes may indicate a viral infection.
A high percentage of neutrophils may indicate bacterial infection.
A high WBC count may indicate infection, immune disorders or allergic responses.
An increased number of eosinophils may indicate allergic responses.
143
Why would a differential blood count be informative in distinguishing UTI from other conditions? Check all that apply.
An increased number of eosinophils may indicate allergic responses.
An increased number of lymphocytes may indicate a viral infection.
A high WBC count may indicate infection, immune disorders or allergic responses.
A high percentage of neutrophils may indicate bacterial infection.
144
In diagnosing UTI, what will the doctor look for in the urine analysis test? Check all that apply.
The presence of bacteria
The presence of red blood cells (RBCs)
The presence of white blood cells (WBCs)
145
Female's urethra is shorter than male's, and closer to the anus, making it easier for fecal bacteria such as K. pneumoniae to cause UTI
Do you know how to tell the difference between a common cold and the flu?
low fever common cold
high fever flu
mild muscle pain common cold
sneezing common common cold
severe muscle pain flu
sneezing rare flu
146
Which of the following is true about the rapid influenza diagnostic test (RIDT) tests? Check all that apply.
Tend to produce false-negative
Lack sensitivity
147
Which of the following are common signs and symptoms of salmonellosis? Check all that apply.
Nausea
Vomiting
Watery diarrhea
148
Why do doctors not prescribe antibiotics for many diarrhea patients? Check all that apply.
Because in bacterial diarrhea, sometimes using antibiotics can delay the excretion of bacteria
Because in bacterial diarrhea, sometimes using antibiotics can cause the release of toxin and make the condition worse
Because for diarrhea, rehydration therapy is more important
149
examples of chronic disease
Heart Disease.
Stroke.
Diabetes.
Cancer.
Obesity.
Arthritis
150
Which of the following constantly sheds dead cells along with any microbes that may be attached to those cells?
epidermis
151
Proteins found in blood plasma are involved in the nonspecific innate immune response and include which of the following? Mark all that apply.
Cytokines
Complement proteins
Acute-phase proteins
152
White blood cells are also referred to as which of the following?
leukocytes
153
_____________ are similar to basophils, but reside in tissues rather than circulating in the blood.
Mast cells
154
The ________ is the part of the body responsible for regulating body temperature.
hypothalamus
155
B cells mature in the _______ and are responsible for _______ immunity.
bone marrow/humoral
156
What is involved in the process of thymic selection? Mark all that apply.
Apoptosis of thymocytes that will interact with self-antigens.
Positive selection of thymocytes that will interact appropriately with MHC molecules.
157
The coordination between B cells and helper T cells that are specific to the same antigen is referred to as ___________.
linked recognition
158
Match each type of vaccine with the corresponding example.
live attenuated vaccine, weakened influenza virions that can only replicate in slightly lower temperatures of the nasal are sprayed into the nose. They do not cause serious flu symptoms, but still produce an active infection that induces a protective adaptive immune response
toxoid vaccine, tetanus toxic molecules are harvested and chemically treated to render them harmless, they are then injected into a patient's arm
inactivated vaccine, influenza virus particles grown in chicken eggs are harvested and chemically treated to render them non-infectious. These immunogenic particles are then purified, packaged and administered as an injection
subunit vaccine, the gene for hepatitis B virus surface antigen is injected into a yeast genome. The modified yeast is grown and the virus protein is produced, harvested, purified, and used in a vaccine
159
An example of natural passive immunity would be
a fetus acquiring maternal IgG to the chickenpox virus across the placenta.
160
Antibodies involved in type I hypersensitivities are of the ________ class.
IgE
161
Characterize the diseases as organ-specific or systemic autoimmune disorders.
Celiac disease, organ-specific
MS, systemic
Hashimoto thyroiditis, organ-specific
Myasthenia gravis, systemic
Type I diabetes, organ-specific
162
For a transplant to have the best chances of avoiding rejection, the genes coding for the ________ molecules should be closely matched between donor and recipient.
MHC
163
Unlike primary immunodeficiencies, which have a genetic basis, secondary immunodeficiencies are often ___________ if the underlying cause is resolved.
reversible
164
What is the most common animal used in production of monoclonal antibodies?
mouse
165
Compare polyclonal Ab with monoclonal Ab.
Produce large quantities of specific Ab, monoclonal Ab
Produce large quantities of nonspecific Abs, Polyclonal Ab
Inexpensive to produce, Polyclonal Ab
Expensive to produce, monoclonal Ab
166
Soluble antigens are detected in this type of test.
Precipitation
167
In a direct fluorescent antibody test, which of the following would we most likely be looking for using a fluorescently-labeled mAb?
bacteria in a patient sample
168
The reason that MeV can hijack immune cells to help it spread is because it uses membrane fusion instead of endocytosis to get into host cells. Instead of being destroyed by enzymes released from lysosomes, it replicates in the cytoplasm of the host cell. When the mature virions are released from the host cell, they lyse the host cell. When memory T and B cells are infected, they are destroyed, causing immune amnesia.
The reason that MeV can hijack immune cells to help it spread is because it uses membrane fusion instead of endocytosis to get into host cells. Instead of being destroyed by enzymes released from lysosomes, it replicates in the cytoplasm of the host cell. When the mature virions are released from the host cell, they lyse the host cell. When memory T and B cells are infected, they are destroyed, causing immune amnesia.
169
Compare and contrast Andrew Wakefield's 1998 study and the 2019 Danish study on the link between the MMR vaccine and autism.
Sample # of 12, wakefield study
Sample # of > 657,000, danish study
No control group, wakefield study
Have control group, danish study
No statistics, wakefield study
Have statistics, danish study
170
Match the steps of HIV life cycle with the events.
Adsorption, HIV gp120 binds to receptor such as CD4
Uncoating, release RNA and enzymes into the host cell
Integration, Integrase cuts open host genome and inserts viral dsDNA
Budding, release of new virions from the host cell
171
Which of the following represents protective mechanism of the skin? Check all that apply.
Keratin makes the skin tough and water-proof
Fatty acid creates a dry, salty, acidic environment hostile to microbes
Epidermal layer cells are tightly connected
Top layers of dead cells shredding
172
________ is the fluid portion of a blood sample that has been drawn in the presence of an anticoagulant compound.
Plasma
173
PMNs are another name for:
neutrophils
174
Which of the following is a way for phagocytes to destroy pathogens? Check all that apply.
reactive nitrogen compounds
reactive oxygen species
microcidal defensins
digestive enzymes
175
Phagocytic cells contain ____________ capable of recognizing various pathogen-associated molecular patterns.
Pattern Recognition Receptors
176
Heat and redness, or ________, occur when the small blood vessels in an inflamed area dilate (open up), bringing more blood much closer to the surface of the skin.
erythema
177
Which process involves antibodies cross-linking cells or particles into large aggregates?
agglutination
178
A single antigen molecule may be composed of many individual ________.
epitopes
179
Which type of antigen-presenting molecule is found on all nucleated cells?
MHC I
180
MHC I molecules present: Check all that apply.
processed foreign antigens from proteasomes.
processed self-antigens from proteasomes.
181
Cell surface glycoproteins that can be used to identify and distinguish between the various types of white blood cells are called ______________.
cluster of differentiation molecules
182
What is a superantigen?
a protein that activates T cells in a nonspecific and uncontrolled manner
183
Which of the following would be a BCR?
IgD
184
Which part of the antibody molecule determines what epitope it binds to?
the two arms of the Y
185
A patient gets a cold, and recovers a few days later. The patient's classmates come down with the same cold roughly a week later, but the original patient does not get the same cold again. This is an example of:
Natural active immunity
186
A(n) ___________ pathogen is in a weakened state; it is still capable of stimulating an immune response but does not cause a disease.
attenuated
187
Inflammatory molecules are released by mast cells in type I hypersensitivities; type II hypersensitivities, however, are characterized by which of the following?
cell lysis (cytotoxicity)
188
Which of the following would be most likely to exhibit an allergic response in a sensitive individual?
Ronnie is petting a cat for only the second time in her life.
189
Which of the following would be most likely to exhibit an allergic response in a sensitive individual?
Ronnie is petting a cat for only the second time in her life.
190
Characterize the diseases as organ-specific or systemic autoimmune disorders.
Addison disease, organ specific
Psoriasis, systemic
SLE, systemic
Graves disease, organ specific
RA, systemic
191
In _______________, antigen-presenting cells in the donated bone marrow may see the host cells as non-self and once activated, the donor's T cells attack the recipient's cells.
Graft-vs-Host disease
192
All but which one of the following are examples of secondary immunodeficiencies?
chronic granulomatous disease
193
The property of a test to detect even small amounts of antibodies or antigens that are test targets is ________.
sensitivity
194
What is the most common reason that prevents monoclonal antibodies from being widely used? Check all that apply.
Costly production
Long production time
195
Which statement is correct for the cross match test?
Can be used to quickly test the compatibility of a donor's blood test for transfusion
196
In an enzyme immunoassay, the enzyme:
is bound to the constant region of the secondary antibody.
197
How does sickle hemoglobin differ from normal hemoglobin? Check all that apply.
Sickle hemoglobin have a tendency to form aggregate
Sickle hemoglobin can stretch the RBCs into sickled shape
Sickle hemoglobin are more hydrophobic
198
Arrange the sites of MeV infection in the correct order.
URT epithelial cells and APCs
Regional lymph nodes
Bloodstream
Skin, spleen, thymus, lungs, liver, and kidneys
199
What samples should be taken for measles lab tests? Check all that apply.
Blood
Throat swab
200
Which of the following is NOT a characteristics of HIV?
DNA genome
201
Match the phases of HIV infection with the descriptions.
High viral load and high T cell count, acute phase
Low viral load, chronic phase
High viral load and low T cell count, AIDS
202
What does having the CCR5 delta 32 mutation reduce the chance of getting HIV infection?
CCR5 is the coreceptor on T cells that helps HIV gp120 binding to CD4
203
Which of the following contributed to the early spread of HIV? Check all that apply.
Blood transfusion contamination
Urban sex trade
Railway building making traveling easier
Re-use of needles in clinics
204
Disruption of the _________________ by the damaging effects of smoking or diseases such as cystic fibrosis can lead to increased colonization of bacteria in the lower respiratory tract and frequent infections.
mucociliary escalator
205
The term __________ refers to the coating of a pathogen by a chemical substance that allows phagocytic cells to recognize, engulf, and destroy it more easily.
opsonization
206
Match each cell type with its description.
Basophil, stains with basic dye methylene blue, has large amount of histamine in granules, and facilitates allergic responses and inflammation
Eosinophil, stains with acidic dye eosin, has histamine and major basic proteins in granules, and facilitates response to protozoa and helminths
natural killer cell, recognizes abnormal cells, binds to them, and releases perforin and granzyme molecules, which include apoptosis
Macrophage, large agranular phagocyte that resides in tissues such as the brain or lungs
207
_____________ are similar to basophils, but reside in tissues rather than circulating in the blood.
Mast cells
208
________, also known as diapedesis, refers to the exit from the bloodstream of neutrophils and other circulating leukocytes.
Extravasation
209
To reach pathogens located in infected tissue, leukocytes must pass through the walls of small capillary blood vessels within tissues which is a process called _________. Mark any that apply.
extravasation
diapedesis
210
Which type of inflammation occurs at the site of an injury or infection?
acute
211
A(n) ________ is a walled-off area of infected tissue that exhibits chronic inflammation.
granulomas
212
The secondary response to an antigen is _______ and _______ when compared to the primary response.
faster/higher
213
Acquired specific immunity involves the response of
B and T lymphocytes.
214
Which type of antigen-presenting molecule is found only on macrophages, dendritic cells, and B cells?
MHC II
215
MHC molecules are used for antigen ________ to T cells.
presentation
216
Order the steps of helper T cell activation in the correct order.
1 TCR recognition of the specific foreign epitope presented with the MHC II antigen binding cleft
2 the MHC II - TCR is anchored ensuring that the T cell know self from non-self
3 the APC and T cell secrete cytokines that activate the helper T cell
4 T helper cell undergoes clonal expansion
Which of the following apply to cytotoxic T cells? Mark all that apply.
APCs or infected nucleated cells presenting antigens associated with MHC I
Destroy cells infected with intracellular pathogens
CD8
217
How long does the primary response lag period last?
10 days
218
Which cells produce specific antibodies?
plasma cells
219
Who is credited at ushering in the modern era of vaccinations?
Edward Jenner
220
The term that describes a phenomenon in which a certain percentage of the population is vaccinated, making it impossible for the microbe to circulate is:
Herd immunity
221
A person who is blood type AB would have IgM hemagglutinin antibodies against type ________ red blood cells in their plasma.
neither A nor B
222
A person who is blood type A would have IgM hemagglutinin antibodies against type ________ red blood cells in their plasma.
B
223
Which of the following is an example of an organ-specific autoimmune disease?
Addison disease
224
Which of the following is an example of a systemic autoimmune disease?
myasthenia gravis
225
Match the transplant with its description.
Autograft, from self to self
Isograft, from identical twin to twin
Xenograft, from animal to human
Allograft, from one human to another
226
Match the immunodeficiency to its correct category.
Selective IgA deficiency, humoral
SCID, both
X-linked agammaglobulinemia, humoral
DiGeorge syndrome, cell-mediated
227
What is the total strength of all interactions in an antibody-antigen complex known as?
Avidity
228
The property of a test to detect only a certain antibody or antigen, and not to react with any others is ________.
specificity
229
Which of the following uses red blood cells as an indicator?
Hemagglutination
230
Which assay is great for visualization of bacteria that might be difficult to isolate from a patient's samples, by allowing fluorescent antibodies to detect the bacteria on a microscope slide?
Direct fluorescent
231
Malaria is caused by a:
protozoan
232
Match the descriptions with the individual's genotype.
High risk of malaria, wild type individual (AA)
Have only normal A form and no problem carrying oxygen, wild type individual (AA)
Low risk of malaria but has a painful disease, Sickle cell anemia patients (SS)
Have only abnormal S form, defective in carrying oxygen, Sickle cell anemia patients (SS)
Low risk of malaria and no disease, Sickle cell carriers (AS)
No problem with oxygen carrying except in low oxygen areas, Sickle cell carriers (AS)
Have some A form and some S form, Sickle cell carriers (AS)
233
Which of the following is the insect vector for malaria?
Anopheles mosquito
234
Most of the specific signs and symptoms of measles appear during the ____ week after exposure.
Second
235
How is measles transmitted? Check all that apply.
Indirect airborne transmission
Direct contact with droplets
236
At what stage of the disease are someone with an active measles infection contagious? Check all that apply.
Period of illness
Prodromal period
237
WHO declares vaccine hesitancy one of the ten leading threats to global health. Which of the following contributes to vaccine hesitancy in many people? Check all that apply.
People who cannot see the benefits of smallpox or polio vaccines because the successful vaccine programs eradicated the diseases in the US
People who do not trust scientists and trust the information they get from the internet instead
Well-intentioned parents who want to protect their children from harmful side effects of vaccines
People who believe that MMR vaccines cause their children to develop autism
238
Match the phases of HIV infection with the descriptions.
CD4+ helper T cell count > 500, acute phase
CD4+ helper T cell count 200-499, chronic phase
CD4+ helper T cell count < 200, aids
239
Match the steps of HIV life cycle with the events.
Entry, HIV enter host cell through membrane fusion or endocytosis
Reverse transcription, reverse transcriptase converts viral RNA to cDNA
Biosynthesis, active protein and RNA synthesis
Assembly, RNA and proteins assemble into new virion
240
Which of the following contributed to the early spread of HIV? Check all that apply.
Blood transfusion contamination
Reuse of needles in clinics
Urban sex trade
Railway building making traveling easier
241
Why is the PCR test not used for initial screening of HIV?
Because it is too expensive
242
A yeast cell is about 5 um in size in reality but when viewed 1000x magnification it appears
5 mm
243
Which of the following has the highest energy?
UV light < 400 nm
244
Which kind of glycosidic bond (linkage) between glucose molecules is not recognized by the enzymes in your digestive tract?
B 1.4 glycosidic bond
245
If one strand of a DNA molecules has the sequence of Bases 5’-ATTGCA-3’, the other complementary strand would have the sequence:
5’-TGCAAT-3’
246
You are a nurse working in a clinic. A patient with severe dehydration comes in. what kind of IV solution would you use to help rehydrate the patient
Isotonic
247
Bacteria use flagella to move purposefully toward or away from chemical by which of the following
Increasing the length of runs and decreasing the length of tumbles
248
The site for ribosomal RNA synthesis in eukaryotic cells is the
Nucleolus
249
Which of the following statements is incorrect
Ribosomes are membrane-bound organelles that aid in protein synthesis
250
Why do scientists think that evolution if mitochondria happened before the evolution of chloroplasts
Because all eukaryotic cells have mitochondria, and only some of them have chloroplasts
251
The eukaryotic cell membranes contains
Proteins
Phospholipids
Cholesterol
252
a(n) originates from the golgi apparatus as one type of vesicle that contains a variety of enzymes for intracellular digestion
Lysosome
253
The cytoskeleton
Anchors organelles
Helps maintain cell shape
Provides support
Provides motility
254
Which of the following is not a difference between bacterial and eukaryotic genomes?
They contain genetic material
255
Which of the following is not part of the endomembrane system?
Mitochondria
256
Which of the following sars-cov-2 variant causes the most severe symptoms
Delta
257
Cytokine storm happens at which stage of covid-19
Pulmonary
Hyperinflammation
258
What does the Ro number indicate
How contagious a disease is
How easy it is for a pathogen to be transmitted from one infected person to other individuals
259
Pseudomonas aeruginosa is often isolated from the lung tissues of cystic fibrosis patients
Which oxygen category does it belong to
Obligate aerobe
260
Which toxin is specifically responsible for systemic disease of HUS
Shiga toxins
261
Which of the following is a true about mycobacterium tuberculosis
Mycolic acid
Acid-fast positive
Wrinkled colonies
262
Which of the following is resistant to both rifampin and isoniazid
MDR TB
263
The main contributing factor to evolution of MDR-TB is
The slow growth of mycobacterium tuberculosis requires antibiotic therapy for months rather than days, which is hard to sustain in some populations, cutting the regimen short allows the resistant bacteria to flourish
264
All of the following pertain to tuberculosis except
Antimicrobials cannot treat and cure tuberculosis
265
Which term best describes the relationship between humans and our microbiota
commensalism
Mutualism
266
Which of the following conditions have been associated with dysbiosis?
IBD
Neurodegenerative disease\asthma
CV diseases
267
Coffee has a pH of approximately 5, what kind of microbe can grow in your coffee
Acidophile
268
A simple and rapid test to distinguish aerotolerant anaerobes from facultative anaerobes is to test for the enzyme
Catalase
269
Which of the following reflects the stages of binary fission in the correct order
Replication of the chromosome, formation of central protein band, septum divides daughter cells
270
When electrons are removed from nutrients via an oxidation reaction, the coupled reduction ration may be
FAD to FADh2
NAD+ to NADH
Which o the following is the purpose of fermentation
To make NAD+
271
Which of the following is the enzyme that replaces the RNA nucleotides in primer with DNA nucleotides
DNA polymerase 1
272
During the elongation period of DNA replication, the leading strand is bult faster than the lagging stand because
The leading strand is synthesized continuously, and the lagging strand is synthesized discontinuously
273
Which of the following is not a function of the 5’ cap and 3’ poly-A tail of a mature eukaryotic mRNA molecule
To facilitate splicing
274
In transcription, the coding strand DNA has the complementary sequence to the mRNA sequence
False
275
Vertical gene transfer happens when
A bacterium divides via binary fusion
276
Which is incorrect about inducible operons
Have genes turned off by a buildup of end products
277
How does sickle hemoglobin differ from normal hemoglobin
Sickle hemoglobin are more hydrophobic
Sickle hemoglobin have a tendency to from aggregate
Sickle hemoglobin cab stretch the RBCs into sickle shape
278
Which of the following is true about restriction enzymes
They are endonucleases
They are DNases
279
In a PCR assay, which of the following is a the best definition of template
The region of DNA sequence that will be copied
280
Strains of MRSA are usually resistant to
Multiple antibiotics
281
Protective features of the skin include all but
High pH
282
Which of the following is true about S. aureus
It is found in the normal microbiota of many people
283
Which of the following are apart of the peripheral nervous system (PNS)
Nerves
Nerve ganglia
284
Which of the following is true about the blood-brain barrier (BBB)
Tight junctions form in between the endothelial cells
Make It harder for pathogens to enter the CNS
Make it harder for drugs to enter CNS
285
Which of these are specific symptoms of meningitis
Photophobia
Stiff neck
286
Which of the following can be used to diagnose listeriosis
Culture of bacteria from blood or CSF samples
Cold enrichment by culturing samples at 4C for a week or more
Gram stain showing gram-positive rod bacteria
Pulsed-field gel electrophoresis or hybridization using DNA probe to detect unique DNA signatures
287
A pregnant woman's doctor suspects she has a listeria infection. The absence of bacteria from the amniotic fluid cultures means that she is not infected with listeria
false
288
Alcohols
Dissolve membrane lipids at concentrations of greater than 50%
Can be used to disinfection or antisepsis
Are limited in effectiveness due to rapid evaporation
289
The greatest number of pathogens enters the body through the
Respiratory system
Which o the following is an opportunistic pathogen
S. epidermidis
290
When would koch's postulates be utilized?
Determination of the cause of a new disease in a microbiology research lab
Nosocomial infections involve all of the following except
Are only transmitted by medical personnel
291
A-B toxins, which are intracellular targeting toxins, are produced by some of the following diseases
Diphtheria
Cholera
Anthrax
Tetanus
292
Which of the following is true about tetanus toxin
Target interneurons
Prevent GABA secretion
293
Fomites, food, and air serve as indirect transmission routes of pathogens
True
294
What is the relationship between basic reproduction number of a pathogen and the herd immunity threshold of the disease
the higher the Ro is, the higher the higher the herd immunity threshold would be
295
All the following are signs and symptoms of urinary tract infections except
Diarrhea
296
Which category of antibiotic resistance does carbapenemase belong to
Drug modification or inactivation
297
Which of the following are characteristics of salmonella ssp
Non-coliform
psychrophile
