MICROBIOLOGY COMPILED EXAM
REVISION QUESTIONS AND THEIR
ANSWERS 100% GUARANTEED
PASS
Microbes have very narrow optimum temperature ranges.
Which of the following classifications of microbes are most
likely to cause human disease, based on temperature
requirements?
hyperthermophiles
thermophiles
mesophiles
psychrophiles
Mesophiles - The temperature range of mesophiles overlaps
that of normal human body temperature, allowing the greatest
growth.
Which of the following statements accurately describes the
culture media necessary for growing Clostridium tetani?
A complex medium is one whose exact chemical composition
is known.
Nutrient agar contains ingredients that combine with oxygen
and remove it, creating an anaerobic environment.
A chemically defined medium is one made up of extracts such
as those from yeasts, meat, or plants whose exact chemical
,composition may vary slightly.
Reducing media are complex media containing chemicals, such
as thioglycolate, that combine with oxygen, creating an
anaerobic environment.
Reducing media are complex media containing chemicals, such
as thioglycolate, that combine with oxygen, creating an
anaerobic environment.
Bacteria that can grow in the presence or absence of oxygen
(O2) are called __________.
facultative anaerobes
obligate anaerobes
microaerophiles
obligate aerobes
Facultative anaerobes - are able to use oxygen if it is present
but also to grow in the absence of oxygen, although with
decreased efficiency.
E
Which tube shows the expected growth pattern for a
microaerophile?
Which enzyme catalyzes the reaction: O2- + O2- + 2H+ → H2O2
+ O2?
superoxide dismutase
oxidase
catalase
peroxidase
,superoxide dismutase
The term aerotolerant anaerobe refers to an organism that:
is killed by oxygen.
uses oxygen or grows without oxygen.
requires more oxygen than is present in air.
requires less oxygen than is present in air.
does not use oxygen but tolerates it.
does not use oxygen but tolerates it.
A culture medium on which only gram-positive organisms
grow and a yellow halo surrounds Staphylococcus aureus
colonies is called a(n)
selective medium.
differential medium.
enrichment culture.
selective and differential medium.
differential and enrichment culture.
selective and differential medium.
A culture medium consisting of agar, peptone, and beef heart
is a
reducing medium.
selective medium.
chemically defined medium.
differential medium.
complex medium.
complex medium.
, Through metabolism, pathogens often produce acids that
interfere with their own growth. __________ are/is added to
media to control pH changes.
Salts
pH indicators
Buffers
Growth inhibitors
Oxygen
Buffers
An organism that you are studying grows at 4°C and at 25°C.
However, it grows best at 20°C. This organism would be
classified as a __________.
psychrophile
thermophile
halophile
mesophile
psychrotroph
psychrotroph
To look for bacteria that degrade petroleum, a culture medium
containing crude oil, sodium nitrate, phosphate buffer, and
REVISION QUESTIONS AND THEIR
ANSWERS 100% GUARANTEED
PASS
Microbes have very narrow optimum temperature ranges.
Which of the following classifications of microbes are most
likely to cause human disease, based on temperature
requirements?
hyperthermophiles
thermophiles
mesophiles
psychrophiles
Mesophiles - The temperature range of mesophiles overlaps
that of normal human body temperature, allowing the greatest
growth.
Which of the following statements accurately describes the
culture media necessary for growing Clostridium tetani?
A complex medium is one whose exact chemical composition
is known.
Nutrient agar contains ingredients that combine with oxygen
and remove it, creating an anaerobic environment.
A chemically defined medium is one made up of extracts such
as those from yeasts, meat, or plants whose exact chemical
,composition may vary slightly.
Reducing media are complex media containing chemicals, such
as thioglycolate, that combine with oxygen, creating an
anaerobic environment.
Reducing media are complex media containing chemicals, such
as thioglycolate, that combine with oxygen, creating an
anaerobic environment.
Bacteria that can grow in the presence or absence of oxygen
(O2) are called __________.
facultative anaerobes
obligate anaerobes
microaerophiles
obligate aerobes
Facultative anaerobes - are able to use oxygen if it is present
but also to grow in the absence of oxygen, although with
decreased efficiency.
E
Which tube shows the expected growth pattern for a
microaerophile?
Which enzyme catalyzes the reaction: O2- + O2- + 2H+ → H2O2
+ O2?
superoxide dismutase
oxidase
catalase
peroxidase
,superoxide dismutase
The term aerotolerant anaerobe refers to an organism that:
is killed by oxygen.
uses oxygen or grows without oxygen.
requires more oxygen than is present in air.
requires less oxygen than is present in air.
does not use oxygen but tolerates it.
does not use oxygen but tolerates it.
A culture medium on which only gram-positive organisms
grow and a yellow halo surrounds Staphylococcus aureus
colonies is called a(n)
selective medium.
differential medium.
enrichment culture.
selective and differential medium.
differential and enrichment culture.
selective and differential medium.
A culture medium consisting of agar, peptone, and beef heart
is a
reducing medium.
selective medium.
chemically defined medium.
differential medium.
complex medium.
complex medium.
, Through metabolism, pathogens often produce acids that
interfere with their own growth. __________ are/is added to
media to control pH changes.
Salts
pH indicators
Buffers
Growth inhibitors
Oxygen
Buffers
An organism that you are studying grows at 4°C and at 25°C.
However, it grows best at 20°C. This organism would be
classified as a __________.
psychrophile
thermophile
halophile
mesophile
psychrotroph
psychrotroph
To look for bacteria that degrade petroleum, a culture medium
containing crude oil, sodium nitrate, phosphate buffer, and
