You are tasked to isolate and grow some weaponised Anthrax. You would perform this in a?

a) Physical Containment level 4 (PC-4) area

Correct transport of bacterial specimens is incredibly important. Which of these requirements DO NOT apply?

a) Select most suitable growth medium to ensure the bacteria is growing

What is the method for quantifying the bacteriophages?

B. Count the plaques (PFU) produced by the bacteriophages

Chocolate agar contains?

a) Heat-treated sheep red blood cells

Which of these methods are NOT suitable for inactivation of bacteria?

a) Depriving the bacteria of nutrients

Plasmids in bacteria:

a) Are non-essential for bacterial growth

Which of the following is NOT an antibiotic resistance mechanism?

a) RNA dependant RNA polymerase activity

What is the difference between Holotrichs and Oligotrichs in terms of substrate utilization in the rumen?

c) Holotrichs cannot degrade cellulose and hemicellulose

a) Presence of bacteria and toxins in the blood

Why do we need to homogenize the tissue samples for virus isolation?

B. To release the viral particles form the cell

Which of these is a non-preferred method for long-term storage of bacteria?

a) In an incubator at 37 degrees Celcius

You conducted a bacterial viable count assay. Which plate do you use to obtain your viable count?

a) 10*-6 dilution (194 colonies)

You determine the H & O antigen serotypes of Salmonella using an agglutination test. What are O & H antigen serotypes?

a) H antigen i and O antigen 4, 5

What is a commensal bacteria?

a) Bacteria living on or within a host without usually causing disease.

When Gram staining bacteria, which of these steps requires critical timing?

a) Decolourisation with ethanol

Which of these is NOT an attribute of disease causing bacteria?

a) Thick peptidoglycan cell wall

What is the definition of Arbovirus?

A virus that is transmitted by arthropod vectors

In terms of antimicrobial stewardship, what are the 5 “R’s”

a) Reduction, Refinement, Replacement, Responsibility and Review

What does biosafety mean (in simple word)?

A. Protects people from germs (Keeping the work space safe)

Which of these best describes a serological test for identification of bacteria?

a) Agglutination reaction using antibodies specific for the bacteria

studbud

Microbiology Past Exam MCQ Part 1

100 termsStudBud Administration10 plays

Imported from external platform

Flashcards100 cardsFPractice quizPHost liveL

Questions 100

Answers

1
What is the most suitable red blood cell (RBC) for haemagglutination test for Newcastle disease virus?
A. Human RBC
B. Chicken RBC
C. Mice RBC
D. Rabbit RBC
2
You are tasked to isolate and grow some weaponised Anthrax. You would perform this in a?
a) Physical Containment level 2 (PC-2) area
a) Physical Containment level 1 (PC-1) area
a) Physical Containment level 3 (PC-3) area
a) Physical Containment level 4 (PC-4) area
3
Which of these is NOT a mechanism of genetic recombination?
Conjugation
Conduction
a) Transduction
a) Transformation
4
If you feed roughage to your cow, what is the main volatile fatty acid produced in the rumen?
c) Butyric acid
b) Propionic acid
a) Acetic acid
d) Valeric acid
5
Correct transport of bacterial specimens is incredibly important. Which of these requirements DO NOT apply?
a) Non-nutritional, semi-solid agar containing salts and buffer
a) Hold bacteria in “suspended animation” until arrival at the laboratory
a) Keep sample at 4 degrees Celcius
a) Select most suitable growth medium to ensure the bacteria is growing
6
What is the method for quantifying the bacteriophages?
A. Count the lysed bacterial cells under the microscope
C. Count the number of the bacteriophages under the light microscope
D. Count the number pf lysogenic bacteriophages
B. Count the plaques (PFU) produced by the bacteriophages
7
Chocolate agar contains?
a) Fastidious bacteria so non-fastidious bacteria can grow
a) 5% intact sheep red blood cells
a) Heat-treated sheep red blood cells
a) 5% cooking chocolate
8
Which Biosafety level laboratory is settable for handling moderate-risk agents that cause human disease?
A. Biosafety level 1
C. Biosafety level 3
B. Biosafety level 2
D. No Biosafety level for moderate risk is required
9
What temperature range (in degrees Celcius) would you incubate a psychrophilic bacteria at?
25-40
55-80
65
<20
10
What colour will a Gram positive bacteria stain following the Gram stain procedure?
Pink
Purple
Red
Green
11
Administering antibiotics to animals in a whole herd scenario is known as:
a) Metaphylactic
a) Growth promoting
a) Therapeutic
a) Prophylactic
12
What is the main difference between “apoptosis” and “necrosis” in viral infections?
No cell death in necrosis
No cell death in apoptosis
No inflammation in apoptosis
No virus production in necrosis
13
Which of these methods are NOT suitable for inactivation of bacteria?
a) Autoclaving (121o degrees Celcius @ 100kPa for 15 minutes)
a) Incineration
a) Depriving the bacteria of nutrients
a) Gamma irradiation
14
After incubation you notice that the Sheep Blood Agar is unchanged under bacterial growth. You conclude that it is:
a) Alpha haemolysis
a) Gamma haemolysis
a) Beta haemolysis
a) Plate requires further incubation
15
Long pili (sex pili) are involved in?
a) Motility
a) Attachment
a) Cell division
a) Conjugation
16
What colour will a Gram negative bacteria stain following the Gram stain procedure?
Purple
Green
Pink
Red
17
Plasmids in bacteria:
a) Bacteria do not contain plasmids
a) Are essential for bacteria growth
a) Are non-essential for bacterial growth
a) Replicate entirely dependent of chromosomal replication
18
Which of the following is NOT an antibiotic resistance mechanism?
a) Impermeability of the drug
a) Alternative metabolic pathway
a) Production of an enzyme that destroys the antibiotic
a) RNA dependant RNA polymerase activity
19
What is the difference between Holotrichs and Oligotrichs in terms of substrate utilization in the rumen?
d) Oligotrichs cannot degrade starch and pectin
b) Oligotrichs cannot degrade hemicellulose and cellulose
c) Holotrichs cannot degrade cellulose and hemicellulose
a) Holotrichs cannot degrade protein and sugars
20
Septicaemia is?
a) Presence of bacteria and toxins in the blood
a) Presence of bacteria or toxins in faeces
a) Large amounts of toxin producing bacteria on the septica
a) Temporary bacterial presence in blood
21
Lytic infection by the herpes simplex virus happens in which of the following cells?
Epithelial cells
Bone marrow cells
Neuron cells
Liver cell
22
What is the main source of envelope proteins in virus structure?
Both host cells and viral encoded proteins
Virus encoded proteins
Immune cell encoded proteins in response to infections
Host cell encoded proteins
23
A bacteria that will grow in the presence and absence of oxygen is an?
Bacteria will grow in any atmosphere
Facultative anaerobe
Aerobe
Anaerobe
24
Which of these is NOT a function of a glycocalyx?
a) Protection from desiccation
a) Resisting phagocytosis
a) Conjugation
a) Attachment
25
Why do we need to homogenize the tissue samples for virus isolation?
C. To neutralize the DNAse and RNAse
D. To neutralize the proteases
A. To remove the bacterial contaminations
B. To release the viral particles form the cell
26
Which virus did we use for coverslip staining to see the intra-nuclear inclusion bodies in cell cultures?
D. Poxvirus
C. Newcastle disease virus
B. Herpesvirus
A. Adenovirus
27
What is the most common route for virus shedding in systemic viral infections?
B. Body fluid and aerosols
D. Arthropods
C. Urine and faeces
A. Blood transfusion
28
What is the main reason for activation of latent infections?
C. Immunosuppression
B. Allergic reactions
D. Stimulation of immune system
A. Re-infection with the same virus
29
Which of these is a non-preferred method for long-term storage of bacteria?
a) -80 degrees Celcius freezer
a) In an incubator at 37 degrees Celcius
a) Freeze dried
a) Agar slant stored at 4 degrees Celcius
30
You conducted a bacterial viable count assay. Which plate do you use to obtain your viable count?
a) 10*-1 dilution (300,000 colonies)
a) 10*-6 dilution (194 colonies)
a) 10*-8 dilution (2 colonies)
a) 10*-2 dilution (30,000 colonies)
31
You determine the H & O antigen serotypes of Salmonella using an agglutination test. What are O & H antigen serotypes?
a) H antigen i and O antigen 6,7
a) H antigen c and O antigen 4, 5
a) H antigen c and O antigen 6,7
a) H antigen i and O antigen 4, 5
32
What are the substrates utilised by Oligotrichs (aka Entodiniomorphs) in the rumen?
d) all answers are correct
c) Starch
a) Cellulose
b) Hemicellulose
33
Which of the following viruses has the highest viral infectivity and transmissibility (highest R0 index)?
B. Seasonal influenza viruses
A. Omicron strains of COVID 19
C. Alpha strains of COVID 19
D. Pandemic influenza viruses
34
What is a commensal bacteria?
a) Bacteria only found in food stuffs
a) Pathogen not normally living on or in a host
a) Bacteria that usually causes only minor disease
a) Bacteria living on or within a host without usually causing disease.
35
What is the etiologic agent of liver abscess in ruminants?
d) Streptococcus bovis
c) Fusobacterium necrophorum
b) Escherichia coli
a) Treponema saccharophilum
36
By which of the following mechanisms can Infectious Bursal Disease virus (IBD) cause cell death in infected cells?
C. Production of toxic proteins
D. Induction of apoptosis
A. Production of giant cells
B. Induction of telomerase activity
37
When Gram staining bacteria, which of these steps requires critical timing?
a) Safranin
a) Crystal violet
a) Decolourisation with ethanol
a) No steps are critical
38
Which of these is NOT an attribute of disease causing bacteria?
a) Be able to produce harm to host tissues
a) Thick peptidoglycan cell wall
a) Be able to survive or evade the host defence mechanisms
a) Must be able to colonise surface of host in competition with microbes
39
In a Gram stain, a bacteria with a thick peptidoglycan cell wall will stain?
Blue
Purple
Pink
Red
40
What is the definition of Arbovirus?
A virus that is transmitted by air
A virus that is capable of causing cancer
A virus that is transmitted by arthropod vectors
A virus that is transmitted by water
41
After incubation you notice that the Sheep Blood Agar has cleared under the colonies. You conclude that it is:
a) Alpha haemolysis
a) Gamma haemolysis
a) Plate requires further incubation
a) Beta haemolysis
42
Which of these would be described as a Gracilicute?
a) Coronaviruses
a) Bacteria lacking a cell wall
a) Thin cell wall
a) Thick cell wall
43
What temperature range (in degrees Celcius) would you incubate a mesophilic bacteria at?
55-80
65
25-40
<20
44
Which of these is NOT a mechanism of action of antimicrobial substances?
a) Inhibition of cell membrane function
a) Interference in DNA synthesis
a) Inhibition of protein synthesis
Transduction
45
In terms of antimicrobial stewardship, what are the 5 “R’s”
a) Re-administer, Rotate, Regulation, Retrospect and Reveal
a) Re-administer, Regulation, Role, Retrospect and Reveal
a) Reduction, Refinement, Replacement, Responsibility and Review
a) Route of adminstration, Regulation, Role, Reveal and Rotate
46
What does biosafety mean (in simple word)?
D. Protect germs from any contamination
A. Protects people from germs (Keeping the work space safe)
B. Protects germs from people (Working safely)
C. Protect environment from any pathogen
47
In terms of antimicrobials, an agent that is bacteriocidal:
a) Slows bacteria growth
a) Aids in bacterial cell division
a) Kills bacteria
a) Provides essential nutrients to bacteria
48
Which of these best describes a serological test for identification of bacteria?
a) Agglutination reaction using antibodies specific for the bacteria
a) Addition of normal serum to nutrient agar
a) Substrate utilisation via detection of end-products
a) Growth of bacteria in liquid media supplemented with serum
49
A bacteria that will grow exclusively in the presence of oxygen is an?
a) Anaerobe
a) Bacteria will grow in any atmosphere
a) Micro-aerophilic
a) Aerobe
50
Which is the main stomach compartment containing microbes that degrade fibre and other feeds?
reticulum
abomasum
omasum
rumen
51
You have completed a Gram stain of an unknown bacteria andobserve long stuick-like, purple staining bacteria. These are:
Cocci
Small circular viruses
Bacilli
Rods
52
Dissemination of viruses from basal part of the cells causes:
Slow infections
Genital infections
Localized infections
Systemic infections
53
Which antibiotic is the bacteria most sensitive to?
a) Enrofloxacilin
a) Imipenem
a) Gentamycin
a) Tetracycline
54
Which of these would be described as a Tenericute?
a) Fungi
a) Bacteria lacking a cell wall
a) Thick cell wall
a) Thin cell wall
55
What are the main volatile fatty acids produced in the rumen during anaerobic fermentation?
c) acetic, butyric and valeric acids
d) propionic, butyric and valeric acids
a) acetic, propionic and butyric acids
b) acetic, propionic and valeric acids
56
Which of the following proteins plays a major role in giant cell formation?
C. Matrix protein
D. Panton protein
A. Fusion protein
B. Clathrin protein
57
Bacteraemia is?
a) Temporary bacterial presence in blood
a) Presence of bacteria and toxins in the blood
a) A rare condition in goats resulting in hair loss
a) Presence of bacteria in faeces
58
The main functions of pili are?
a) Attachment to cell surfaces and conjugation
a) Vestigial structure with no known function
a) Motility and conjugation
a) Attachment to cell surfaces and motility
59
Which of the following RNA viruses has proof reading activity in their genome?
B. All RNA viruses has the genome proof reading activity
C. Proof reading activity exists in double stranded RNA viruses
A. No proof reading exists in the genome RNA viruses
D. Proofreading activity has been observed in COVID-19 viruses
60
How can bloating be prevented in ruminants?
c) dont put cows straight onto pasture with high legume content when hungry
d) all answers are correct
a) use grazing pastures with at least 50% grass
b) dont put cows onto pasture with high legume content if pasture is wet
61
You have just completed a Gram stain of an unknown bacteria andobserve round, purple staining bacteria. These are:
Rods
Small circular viruses
Bacilli
Cocci
62
What type of feed promotes an increase in propionic acid?
c) urea
d) silage
b) barley grains
a) hay
63
What advantages do the symbiotic relationship provide to ruminants?
a) microbes can degrade fibre but not protein
c) microbial cells can serve as a source of proteins but not vitamins
b) microbes can use non-protein nitrogen as source of ammonia
d) microbial cells can serve as a source of vitamins but not proteins
64
MRSA is a pathogenic bacteria that has evolved to confer resistance to antibiotic. What does MRSA stand for?
a) Microbiota Residual Staphylococcus aureus
a) Maltose Resistant Staphylococcus aureus
a) Many Resistant Staphylococcus aureus
a) Methicillin Resistant Staphylococcus aureus
65
What is the contribution of ciliated protozoa to ruminal digestion?
c) increases bacterial numbers
a) can increase the rate of starch fermentation
b) actively participate in ruminal digestion
d) decreases protein degradation
66
What is the best sample for virus isolation from post-mortem animals in systemic infections?
C. Reticuloendothelial organs
B. Whole blood
A. Brain and muscles
D. Kidney and intestinal fluids
67
What are the substrates utilised by Holotrichs in the rumen?
b) Hemicellulose
d) all answers are correct
a) Cellulose
c) Starch
68
Which of these statements more correctly describes the biological process known as recombination?
Sudden, heritable change induced by the introgenetic material from in cell
Sudden, heritable change induced by intro of genetic material from out cell
Slow change of genetic material from outside the cell
Slow change of genetic material from inside the cell
69
Chocolate agar is used to isolate?
a) Protozoans
a) Non-fastidious bacteria
a) Foot and Mouth Disease virus
a) Fastidious bacteria that require Factors V and X for growth
70
Plasmid DNA in bacteria is:
a) Smaller in size (base-pairs) than bacterial chromosomal DNA
a) Larger in size (base-pairs) than bacterial chromosomal DNA
a) Bacteria do not contain plasmid DNA
a) The same size (base-pairs) as bacterial chromosomal DNA
71
Which of these statements is incorrect?
a) Bacterial plasmids encode antibiotic resistance genes
a) Bacterial plasmids encode virulence factors
a) Bacterial plasmids encode genes for sex pili
a) Bacterial plasmids encode all the genes essential for bacterial survival
72
What is a prophage?
C. Replication phase of bacteriophage DNA at the early step of replication
D. Bacteriophage DNA in wild type lytic bacteriophages
A. Bacteriophage DNA that integrated in to the cellular chromosome
B. A premature bacteriophage before releasing from the cell
73
In a Gram stain, a bacteria with a thin peptidoglycan cell wall will stain?
Thin cell walls remain colourless
Purple
Red
Blue
74
What are the vitamins produced by ruminal microbes?
b) vitamin K
c) vitamin A, D and E
d) all B-complex vitamins and vitamin K
a) B-complex vitamins
75
Re-assortment of genes may occur with:
C. Foot and Mouth disease virus
D. Newcastle disease virus
B. Influenza A virus
A. Human Immunodeficiency virus
76
Which of these is not a component of bacterial growth phases?
a) Lag phase
a) Death phase
a) Logarithmic or exponential phase
a) Transduction phase
77
You plated bacteria on McConkey agar and noticed growth of pinkish coloured colonies. You can deduce the bacteria is:
Non-lactose fermenting
Lactose fermenting
Glucose fermenting
Gram positive
78
What is the first discovered animal virus?
Foot and mouth
Influenza
Yellow fever virus
Rabies
79
What is the main end product produced by rumen Archae?
b) Propionate
d) Formate
c) Methane
a) Acetate
80
Endospores are?
a) Involved in plasmid transfer between bacteria
a) Tiny bacteria
a) Dormant stages of large Gram positive rods
a) Produced by fungi
81
What are the strategies used to reduce greenhouse gas emissions from ruminants?
d) all answers are correct
a) Antibiotics
c) Bromoform
b) Unsaturated fatty acids
82
The main function of Flagella in bacteria is:
a) Attachment to cell surfaces
a) Vestigial structure with no known function
a) Motility
a) Replication of plasmid DNA
83
You plated bacteria on McConkey agar and noticed growth but absence of pink colouring. You can deduce the bacteria is:
Non-lactose fermenting
Lactose Fermenting
A contaminant
Glucose fermenting
84
Which of these would be described as a Firmicute?
a) Coronaviruses
a) Bacteria lacking a cell wall
a) Thin cell wall
a) Thick cell wall
85
What is the best time for taking a blood sample for virus isolation from live animals with systemic infections?
B. Before onset of fever
A. Soon after onset of symptoms
C. After the fever decreases
D. Last stage of disease
86
What happens with the ruminal pH if there is an accumulation of volatile fatty acids?
b) pH decreases
c) pH increases
d) pH decreases and lactic acid remains the same
a) pH increases and lactic acid production increases
87
Organisms that grow on McConkey agar are generally?
a) Protozoans
a) Gram positive, enteric bacteria
a) Viruses
a) Gram negative, enteric bacteria
88
What is the main microorganism present in the rumen?
a) Ciliated protozoa
c) Archae
d) Bacteria
b) Fungi
89
What is the contribution of fungi to ruminal digestion?
a) can degrade lignin and increase the production of volatile fatty acids
b) contributes to a greater extend to the digestion of grains
c) can degrade starch and utilise lactic acid
d) promotes greater degradation of forage
90
A bacteria that will grow exclusively in the absence of oxygen is an?
a) Anaerobe
a) Aerobe
a) Micro-aerophilic
a) Bacteria will grow in any atmosphere
91
You determine the H & O antigen serotypes of Salmonella using an agglutination test. What are O & H antigen serotypes?
a) H antigen c and O antigen 4, 5
a) H antigen d and O antigen 6,7
a) H antigen c and O antigen 6,7
a) H antigen d and O antigen 4, 5
92
If you feed cereal grains to your cow, what is the main volatile fatty acid produced in the rumen?
c) Butyric acid
d) Valeric acid
b) Propionic acid
a) Acetic acid
93
You do a few 10-fold dilutions. On 10-8 plate you count 35 colonies. How many bacteria are in original sample?
e) 3.5x10*-10
a) 3.5x10*9
a) 3.5x10*10
a) 3.5x10*-9
94
What temperature range (in degrees Celcius) would you incubate a thermophilic bacteria at?
55-80
65
25-40
<20
95
Most of the early proteins in the viral life cycle are:
Envelope proteins
Viral structural proteins
Viral regulatory proteins
Viral ligands
96
After incubation you notice that the Sheep Blood Agar has turned a slight greenish colour. You conclude that it is:
a) Alpha haemolysis
a) Gamma haemolysis
a) Beta haemolysis
a) Plate requires further incubation
97
What causes an accumulation of lactic acid in the rumen?
a) the use of antibiotics
c) accumulation of propionic acid
b) rapid introduction to cereal grains
d) all answers are correct
98
True or false. Bacteria contain plastids?
True
False
99
Sheep Blood Agar contains?
a) A red colour indicator
a) 5% sheep red blood cells
a) 5% goat red blood cells
a) Heat-treated sheep red blood cells
100
What is the main source of viral lipids in virion structure?
Viral matrix proteins
Viral envelope
Viral nucleocapsid
Viral nucleic acid

Microbiology Past Exam MCQ Part 1 Flashcards | StudBud