MMBIO 221 EXAM 3 STUDY GUIDE 2026
TESTED QUESTIONS AND PRACTICE
SOLUTION GRADED A+
◉ Peptidoglycan.
Answer: Gram-positive bacteria, Gram-negative bacteria,
Acid-fast bacteria
◉ Mycolic acids.
Answer: Acid-fast bacteria only
◉ Lipid A.
Answer: Gram-negative bacteria only
◉ Will appear blue after an acid-fast stain.
Answer: A and B only
◉ Cells of the genus Mycoplasma lack which of the following?.
Answer: A cell wall
◉ A red blood cell (RBC) is placed into a hypertonic solution.
,Answer: Crenation
◉ An RBC is placed into a hypotonic solution.
Answer: Swell then burst (lysis)
◉ A plant cell is placed into a hypertonic solution.
Answer: Plasmolysis
◉ A plant cell is placed into a hypotonic solution.
Answer: Nothing happens
◉ An RBC is placed into an isotonic solution.
Answer: Nothing happens
◉ An object measures 0.5 µm. This is equivalent to.
Answer: A. 500 nm
◉ Empty magnification results from increasing magnification
without increasing the.
Answer: resolution
,◉ Assume that a bacterial cell has established a typical proton
gradient. When this gradient is used to
power the transport of lactose into the cell, the process is most
correctly termed.
Answer: Symport
◉ Which of the following microscopes is capable of generating a
three-dimensional image of a specimen?.
Answer: confocal, differential interference contrast, scanning
electron
◉ Gram-positive cells immediately following the primary stain.
Answer: Purple
◉ Gram-negative cells immediately following decolorization.
Answer: Colorless
◉ Gram-negative cells immediately following the primary stain.
Answer: Purple
◉ Gram-positive cells immediately following the counterstain.
Answer: Purple
, ◉ Malachite green is associated with which of the following staining
procedures?.
Answer: Endospore stain
◉ The reason visible light is relatively limited in its usefulness for
microscopy is:.
Answer: its wavelength is too long to enable high resolution of very
small objects
◉ Most stains that stain bacteria well are classified as:.
Answer: Basic (positively-charged chromophores)
◉ The molecule upon which an enzyme acts is known as its:.
Answer: substrate
◉ Glucose goes in; pyruvate, ATP, and NADH come out.
Answer: Gylcolysis
◉ Acetyl-Co-A goes in; NADH, FADH2, and GTP come out.
Answer: Krebs Cycle
◉ Hydrogen atom "juicing"; a proton gradient is formed.
TESTED QUESTIONS AND PRACTICE
SOLUTION GRADED A+
◉ Peptidoglycan.
Answer: Gram-positive bacteria, Gram-negative bacteria,
Acid-fast bacteria
◉ Mycolic acids.
Answer: Acid-fast bacteria only
◉ Lipid A.
Answer: Gram-negative bacteria only
◉ Will appear blue after an acid-fast stain.
Answer: A and B only
◉ Cells of the genus Mycoplasma lack which of the following?.
Answer: A cell wall
◉ A red blood cell (RBC) is placed into a hypertonic solution.
,Answer: Crenation
◉ An RBC is placed into a hypotonic solution.
Answer: Swell then burst (lysis)
◉ A plant cell is placed into a hypertonic solution.
Answer: Plasmolysis
◉ A plant cell is placed into a hypotonic solution.
Answer: Nothing happens
◉ An RBC is placed into an isotonic solution.
Answer: Nothing happens
◉ An object measures 0.5 µm. This is equivalent to.
Answer: A. 500 nm
◉ Empty magnification results from increasing magnification
without increasing the.
Answer: resolution
,◉ Assume that a bacterial cell has established a typical proton
gradient. When this gradient is used to
power the transport of lactose into the cell, the process is most
correctly termed.
Answer: Symport
◉ Which of the following microscopes is capable of generating a
three-dimensional image of a specimen?.
Answer: confocal, differential interference contrast, scanning
electron
◉ Gram-positive cells immediately following the primary stain.
Answer: Purple
◉ Gram-negative cells immediately following decolorization.
Answer: Colorless
◉ Gram-negative cells immediately following the primary stain.
Answer: Purple
◉ Gram-positive cells immediately following the counterstain.
Answer: Purple
, ◉ Malachite green is associated with which of the following staining
procedures?.
Answer: Endospore stain
◉ The reason visible light is relatively limited in its usefulness for
microscopy is:.
Answer: its wavelength is too long to enable high resolution of very
small objects
◉ Most stains that stain bacteria well are classified as:.
Answer: Basic (positively-charged chromophores)
◉ The molecule upon which an enzyme acts is known as its:.
Answer: substrate
◉ Glucose goes in; pyruvate, ATP, and NADH come out.
Answer: Gylcolysis
◉ Acetyl-Co-A goes in; NADH, FADH2, and GTP come out.
Answer: Krebs Cycle
◉ Hydrogen atom "juicing"; a proton gradient is formed.
