BIO 171 MODULE 3 EXAM 2026 LEARNING
MATERIAL COMPLETE QUESTIONS AND
ANSWERS 100% CORRECT
◉ True or False: Staining is often required to image a cell that is
adherent and flat (thin). Answer: True
Adherent, flat and unstained cells are almost invisible due to the
limits on both
resolution and contrast. Therefore, cell staining is often required to
adequately image
the sample.
◉ True or False: A cell that is adherent, flat (thin), and unstained is
easily identified using bright field microscopy Answer: False:
Adherent, flat cells are almost invisible due to the limits on both
resolution and contrast
◉ Which of the following could be seen clearly by the unaided eye?
Select all that apply.
A. Bacteria with diameter of 24 μm
B. Protozoa with diameter of 150 μm
,C. Virus with a diameter of 0.2 μm
D. Skin cell with diameter of 1500 μm Answer: B. Protozoa with
diameter of 150 μm
D. Skin cell with diameter of 1500 μm
The unaided eye can, on average, clearly resolve objects > 100 μm
◉ 2. Which of the following could NOT be seen clearly by the
unaided eye? Select all that apply.
A. Bacteria with diameter of 24 μm
B. Protozoa with diameter of 150 μm
C. Virus with a diameter of 0.2 μm
D. Skin cell with diameter of 1500 μm Answer: A. Bacteria with
diameter of 24 μm
C. Virus with a diameter of 0.2 μm
The unaided eye can, on average, clearly resolve objects > 100 μm
◉ 1. Label the following unmarked microscope components
(numbered arrows) by matching it with the components provided
(letters). Answer: 1F- eyepiece
2D- neck
,3B- fine adjustment knob
4G- objective
5A- stage
6H- base
◉ This type of microscope is best suited for visualizing GFP, RFP, and
YFP proteins. Answer: Fluorescence
◉ This type of microscope utilizes ultraviolet (UV) light to illuminate
stained objects. Answer: Fluorescence
◉ This type of microscope uses a specialized condenser and
objective to amplify the slight differences between cells and
background. Answer: Phase-contrast
◉ This type of microscope enhances contrast between specimen and
background but does not permit the visualization of intracellular
structures. Answer: Dark Field
◉ This type of microscope uses neither halogen nor UV light sources
but rather lasers to illuminate stained cells in high resolution.
Answer: Confocal
, ◉ This type of microscope is capable of capturing images in multiple
focal planes, rendering a specimen in 3-D Answer: Confocal
◉ Identify what type of electron microscope was used to capture the
following image and explain your choice.
(picture labeled B) Answer: The image was captured using a
Scanning Electron Microscope (SEM). The above image shows the
trademark 'shell' image (no subcellular organelles are visible)
reminiscent of SEM. Only TEM is capable of visualizing subcellular
substrucutres.
◉ Identify what type of electron microscope was used to capture the
following image and explain your choice.
(picture labeled A) Answer: The above image is captured via a
Transmission Electron Microscope (TEM). Even at 20nm resolution
(inset image), subcellular substructures are still visible. The image
lacks the outside 'shell' only appearance of SEM.
◉ Gram-Positive cells appear [answer1] in color due to a [answer2]
peptidoglycan layer in the cell wall. Answer: 1. Purple
2. Thick
◉ Gram-Negative cells appear [answer1] in color due to a [answer2]
peptidoglycan layer in the cell wall. Answer: 1. Pink
2. Thin
MATERIAL COMPLETE QUESTIONS AND
ANSWERS 100% CORRECT
◉ True or False: Staining is often required to image a cell that is
adherent and flat (thin). Answer: True
Adherent, flat and unstained cells are almost invisible due to the
limits on both
resolution and contrast. Therefore, cell staining is often required to
adequately image
the sample.
◉ True or False: A cell that is adherent, flat (thin), and unstained is
easily identified using bright field microscopy Answer: False:
Adherent, flat cells are almost invisible due to the limits on both
resolution and contrast
◉ Which of the following could be seen clearly by the unaided eye?
Select all that apply.
A. Bacteria with diameter of 24 μm
B. Protozoa with diameter of 150 μm
,C. Virus with a diameter of 0.2 μm
D. Skin cell with diameter of 1500 μm Answer: B. Protozoa with
diameter of 150 μm
D. Skin cell with diameter of 1500 μm
The unaided eye can, on average, clearly resolve objects > 100 μm
◉ 2. Which of the following could NOT be seen clearly by the
unaided eye? Select all that apply.
A. Bacteria with diameter of 24 μm
B. Protozoa with diameter of 150 μm
C. Virus with a diameter of 0.2 μm
D. Skin cell with diameter of 1500 μm Answer: A. Bacteria with
diameter of 24 μm
C. Virus with a diameter of 0.2 μm
The unaided eye can, on average, clearly resolve objects > 100 μm
◉ 1. Label the following unmarked microscope components
(numbered arrows) by matching it with the components provided
(letters). Answer: 1F- eyepiece
2D- neck
,3B- fine adjustment knob
4G- objective
5A- stage
6H- base
◉ This type of microscope is best suited for visualizing GFP, RFP, and
YFP proteins. Answer: Fluorescence
◉ This type of microscope utilizes ultraviolet (UV) light to illuminate
stained objects. Answer: Fluorescence
◉ This type of microscope uses a specialized condenser and
objective to amplify the slight differences between cells and
background. Answer: Phase-contrast
◉ This type of microscope enhances contrast between specimen and
background but does not permit the visualization of intracellular
structures. Answer: Dark Field
◉ This type of microscope uses neither halogen nor UV light sources
but rather lasers to illuminate stained cells in high resolution.
Answer: Confocal
, ◉ This type of microscope is capable of capturing images in multiple
focal planes, rendering a specimen in 3-D Answer: Confocal
◉ Identify what type of electron microscope was used to capture the
following image and explain your choice.
(picture labeled B) Answer: The image was captured using a
Scanning Electron Microscope (SEM). The above image shows the
trademark 'shell' image (no subcellular organelles are visible)
reminiscent of SEM. Only TEM is capable of visualizing subcellular
substrucutres.
◉ Identify what type of electron microscope was used to capture the
following image and explain your choice.
(picture labeled A) Answer: The above image is captured via a
Transmission Electron Microscope (TEM). Even at 20nm resolution
(inset image), subcellular substructures are still visible. The image
lacks the outside 'shell' only appearance of SEM.
◉ Gram-Positive cells appear [answer1] in color due to a [answer2]
peptidoglycan layer in the cell wall. Answer: 1. Purple
2. Thick
◉ Gram-Negative cells appear [answer1] in color due to a [answer2]
peptidoglycan layer in the cell wall. Answer: 1. Pink
2. Thin
