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BIO 250 Final Exam – Questions With Precise
Solutions
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Terms in this set (69)
A pure culture b
A) is sterile.
B) is a population of identical cells.
C) is made of a precisely defined
chemical medium.
D) contains one microbial cell.
Microbial cells first evolved on Earth c
approximately ________ _______ years ago.
A) 1.6 to 1.8 million
B) 7.0 to 7.2 million
C) 3.8 to 3.9 billion
D) 10.5 to 11.5 billion
E) None of the above
,Predict how Pasteur's conclusions on c
spontaneous generation with swan
flasks
would have changed if he worked
with and maintained the flasks in a
laminar flow
hood (where the air is sterile).
A) Sterilization of the swan flask
solutions would not have been
necessary to reject
spontaneous generation. If he did
sterilize the flasks, the spontaneous
generation
hypothesis would have been
supported.
B) His incubation times would not
have been sufficient to refute
spontaneous
generation.
C) Pasteur's flasks never would have
putrefied, and the experiment would
not have
refuted spontaneous generation.
D) Viruses would have still been
present, and his conclusion would
have been
unchanged.
Of the structures listed below, which d
one is found in the outer most
membrane of a
Gram-negative cell?
A) Ribosomes
B) The peptidoglycan layer
C) The periplasm
D) LPS (lipopolysaccharide) layer
, Gram-positive bacteria stain _____ with c
a Gram stain reaction because they
have a
__________ peptidoglycan layer than
Gram-negative bacteria.
A) red / thinner
B) purple/ thinner
C) purple / thicker
D) red / thicker
Which of the following statement(s) e
is/are correct?
A) Flagella allow bacteria to glide
B) Flagella allow bacteria to swim
C) The directed movement of
bacterial cells in response to a
gradient of a chemical,
is called chemotaxis
D) A and C are correct
E) B and C are correct
Electron microscopy has _________ ________ a
than light microscopy, because the
wavelengths of electrons are much
___________ than the wavelength of visible
light.
A) higher resolution/smaller
B) lower magnification/larger
C) higher resolution/larger
D) lower resolution/smaller
BIO 250 Final Exam – Questions With Precise
Solutions
Save
Terms in this set (69)
A pure culture b
A) is sterile.
B) is a population of identical cells.
C) is made of a precisely defined
chemical medium.
D) contains one microbial cell.
Microbial cells first evolved on Earth c
approximately ________ _______ years ago.
A) 1.6 to 1.8 million
B) 7.0 to 7.2 million
C) 3.8 to 3.9 billion
D) 10.5 to 11.5 billion
E) None of the above
,Predict how Pasteur's conclusions on c
spontaneous generation with swan
flasks
would have changed if he worked
with and maintained the flasks in a
laminar flow
hood (where the air is sterile).
A) Sterilization of the swan flask
solutions would not have been
necessary to reject
spontaneous generation. If he did
sterilize the flasks, the spontaneous
generation
hypothesis would have been
supported.
B) His incubation times would not
have been sufficient to refute
spontaneous
generation.
C) Pasteur's flasks never would have
putrefied, and the experiment would
not have
refuted spontaneous generation.
D) Viruses would have still been
present, and his conclusion would
have been
unchanged.
Of the structures listed below, which d
one is found in the outer most
membrane of a
Gram-negative cell?
A) Ribosomes
B) The peptidoglycan layer
C) The periplasm
D) LPS (lipopolysaccharide) layer
, Gram-positive bacteria stain _____ with c
a Gram stain reaction because they
have a
__________ peptidoglycan layer than
Gram-negative bacteria.
A) red / thinner
B) purple/ thinner
C) purple / thicker
D) red / thicker
Which of the following statement(s) e
is/are correct?
A) Flagella allow bacteria to glide
B) Flagella allow bacteria to swim
C) The directed movement of
bacterial cells in response to a
gradient of a chemical,
is called chemotaxis
D) A and C are correct
E) B and C are correct
Electron microscopy has _________ ________ a
than light microscopy, because the
wavelengths of electrons are much
___________ than the wavelength of visible
light.
A) higher resolution/smaller
B) lower magnification/larger
C) higher resolution/larger
D) lower resolution/smaller
