BIOL 250 Exam 1 Latest Updated 2024 With 100% Correct
Questions And Answers
Electron microscopy has _________ ________ 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 - A
Which of the following statements are false:
A) Poly-β-alkanoates (PHA) such as poly-β-hydroxybutyrate (PHB) are carbon- and
energy-storing polymers that can be used to produce biodegradable plastics.
B) A major function of prokaryotic gas vesicles is to confer buoyancy on cells by
decreasing their density
C) A major function of the cytoplasmic membrane in prokaryotes is to act as a
permeability barrier.
D) Scanning electron microscopy can be used to visualize the different layers of the cell
membrane(s) and cell wall - D
From the standpoint of the microorganism, in glycolysis the useful product(s) are
A) Anabolic intermediates
B) ATP
C) Fermentation products such as lactic acid and ethanol
D) Both (A) and (B)
E) (A), (B), and (C) - D
During respiration electrons from the __________ of substrates are used to ________ a
terminal electron acceptor that is either oxygen (aerobic respiration) or some other
inorganic compound (anaerobic respiration).
A) reduction / oxidize
B) transport / degrade
C) oxidation / reduce
D) none of the above - C
Which intermediate compound(s) in the citric acid cycle is/are often used for
biosynthetic pathways as well as carbon catabolism?
A) α-ketoglutarate
,B) oxaloacetate
C) acetyl~CoA
D) All of the above
E) None of the above - D
Which pathway(s) are used to obtain anabolic intermediates:
A) Pentose phosphate pathway
B) Glycolysis
C) Citric acid cycle
D) All the above
E) None of the above - D
Which statement is FALSE?
A) Electron transport systems mediate transfer of electrons and conserve some of the
energy released during transfer and use it to synthesize ATP
B) In electron transport systems, the electron carriers are membrane associated.
C) Fermentation requires a fully functional electron transport chain so that a proton
gradient can be formed and drive the synthesis of ATP.
D) The proton motive force drives the conversion of ADP to ATP through ATP synthase
-C
A pure culture
A) is sterile.
B) is a population of identical cells.
C) is made of a precisely defined chemical medium.
D) contains one microbial cell. - B
Microbial cells first evolved on Earth 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 - C
Predict how Pasteur's conclusions on 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. - C
Of the structures listed below, which 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 - D
Gram-positive bacteria stain _____ with 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 - C
Which of the following statement(s) 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 - E
By controlling the concentration of nutrients continuously added to a chemostat, cells
can constantly be maintained at the
A) exponential growth phase.
B) stationary growth phase.
C) lag growth phase.
D) death growth phase. - A
A bacterial cell doubles every 30 minutes under given laboratory conditions. When a
liquid broth is inoculated with 10 cells, how many cells will the culture contain after 4
hours?
A) 40
Questions And Answers
Electron microscopy has _________ ________ 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 - A
Which of the following statements are false:
A) Poly-β-alkanoates (PHA) such as poly-β-hydroxybutyrate (PHB) are carbon- and
energy-storing polymers that can be used to produce biodegradable plastics.
B) A major function of prokaryotic gas vesicles is to confer buoyancy on cells by
decreasing their density
C) A major function of the cytoplasmic membrane in prokaryotes is to act as a
permeability barrier.
D) Scanning electron microscopy can be used to visualize the different layers of the cell
membrane(s) and cell wall - D
From the standpoint of the microorganism, in glycolysis the useful product(s) are
A) Anabolic intermediates
B) ATP
C) Fermentation products such as lactic acid and ethanol
D) Both (A) and (B)
E) (A), (B), and (C) - D
During respiration electrons from the __________ of substrates are used to ________ a
terminal electron acceptor that is either oxygen (aerobic respiration) or some other
inorganic compound (anaerobic respiration).
A) reduction / oxidize
B) transport / degrade
C) oxidation / reduce
D) none of the above - C
Which intermediate compound(s) in the citric acid cycle is/are often used for
biosynthetic pathways as well as carbon catabolism?
A) α-ketoglutarate
,B) oxaloacetate
C) acetyl~CoA
D) All of the above
E) None of the above - D
Which pathway(s) are used to obtain anabolic intermediates:
A) Pentose phosphate pathway
B) Glycolysis
C) Citric acid cycle
D) All the above
E) None of the above - D
Which statement is FALSE?
A) Electron transport systems mediate transfer of electrons and conserve some of the
energy released during transfer and use it to synthesize ATP
B) In electron transport systems, the electron carriers are membrane associated.
C) Fermentation requires a fully functional electron transport chain so that a proton
gradient can be formed and drive the synthesis of ATP.
D) The proton motive force drives the conversion of ADP to ATP through ATP synthase
-C
A pure culture
A) is sterile.
B) is a population of identical cells.
C) is made of a precisely defined chemical medium.
D) contains one microbial cell. - B
Microbial cells first evolved on Earth 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 - C
Predict how Pasteur's conclusions on 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. - C
Of the structures listed below, which 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 - D
Gram-positive bacteria stain _____ with 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 - C
Which of the following statement(s) 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 - E
By controlling the concentration of nutrients continuously added to a chemostat, cells
can constantly be maintained at the
A) exponential growth phase.
B) stationary growth phase.
C) lag growth phase.
D) death growth phase. - A
A bacterial cell doubles every 30 minutes under given laboratory conditions. When a
liquid broth is inoculated with 10 cells, how many cells will the culture contain after 4
hours?
A) 40
