BIOD 171 Module 3 Exam Questions Solved 100% Latest Update 2025
Does phase contrast microscopy require staining? - Answers No
Simple staining is used mostly for - Answers A quick observance
Simple straining uses ____________ _________ dye. - Answers Positively charged
True or false: Acid fast staining is used for bacteria resistant to traditional staining. - Answers True
What is acid fast staining mostly used for? - Answers Mycobacterium tuberculosis
Resolution - Answers The distance between two objects as objects can still be seen as separate
Contrast - Answers The difference in light absorbance between two objects and the background
Dark Field Microscopy - Answers Used to view living specimen by reflecting light off of organism
Can you see intracellular structures with a dark field microscope? - Answers No
What microscope can capture in 3D? - Answers Confocal
What are two types of electron microscopes? - Answers Transmission electron microscope (TEM) and
scanning electron microscope (SEM)
What is the main difference between TEM and SEM? - Answers TEM passes through the sample while
SEM reflects off the surface of the sample
Who developed the gram stain and when? - Answers Hans Christian Gram in 1884
Gram positive bacteria has a ________ __________________ ______ ______. - Answers thick
peptidoglycan cell wall
What color will gram positive bacteria stain? - Answers Purple
What color will gram negative bacteria stain? - Answers Pink
Gram negative bacteria has a ________ ________________ ______ _______. - Answers Thin
peptidoglycan cell wall
What is a differential stain? - Answers The use of two or more dyes that react differently with different
kinds/parts of bacteria.
What are two types of cell fixation? - Answers Heat fixation and chemical fixation
What does the Giemsa stain detect? - Answers Blood parasites
True or false: Negative staining stains only the microorganism - Answers False. Negative staining stains
everything BUT the microorganism
, Giemsa stain: what colors does the nucleus and cytoplasm stain? - Answers Nucleus: bluish purple
Cytoplasm: pink
What type of cell does the Giemsa stain? - Answers White blood cells
What type of samples are acid-fast stains often performed on? - Answers Sputum samples (thick mucus
produced in lungs that can be coughed up)
The naked eye can see up to ______ micrometers. - Answers 100 micrometers
Cellular organelles can be as small as ______ micrometers. - Answers 0.2 micrometers
Does phase contrast need staining? - Answers No
What is the difference between phase contrast compared to brightfield? - Answers You are able to
visualize things that would otherwise be invisible; cells are highly distinguishable
What type of microscopy uses lasers? - Answers Confocal
Does electron microscopy use fixation? - Answers Yes
Does electron microscopy use live or dead samples? - Answers Dead
What type of secondary (counterstain) dye called in gram staining? - Answers Safranin
___________________ ______________ microscopy coats samples with gold of platinum. - Answers
Scanning electron microscopy
Does negative staining kill the organism and why? - Answers No. Since negative staining is mildly
invasive, it may not kill the microorganism.
Who is the father of medicine? - Answers Hippocrates
What is microscopy? - Answers Use of light or electrons to magnify objects
What are the two measurements of microscopy? - Answers Micrometer and nanometer
Magnification - Answers Increase the size of object
True or false: Shorter wave lengths increase resolving power. - Answers True
Light microscope - Answers It uses visible light and blue wave lengths for improved resolution.
What is the magnification and resolution of a light microscope? - Answers Magnification: 1x-2000x
Resolution: 10mm-200mm
What are light microscopes used to see? - Answers Whole cells and organelles
Does phase contrast microscopy require staining? - Answers No
Simple staining is used mostly for - Answers A quick observance
Simple straining uses ____________ _________ dye. - Answers Positively charged
True or false: Acid fast staining is used for bacteria resistant to traditional staining. - Answers True
What is acid fast staining mostly used for? - Answers Mycobacterium tuberculosis
Resolution - Answers The distance between two objects as objects can still be seen as separate
Contrast - Answers The difference in light absorbance between two objects and the background
Dark Field Microscopy - Answers Used to view living specimen by reflecting light off of organism
Can you see intracellular structures with a dark field microscope? - Answers No
What microscope can capture in 3D? - Answers Confocal
What are two types of electron microscopes? - Answers Transmission electron microscope (TEM) and
scanning electron microscope (SEM)
What is the main difference between TEM and SEM? - Answers TEM passes through the sample while
SEM reflects off the surface of the sample
Who developed the gram stain and when? - Answers Hans Christian Gram in 1884
Gram positive bacteria has a ________ __________________ ______ ______. - Answers thick
peptidoglycan cell wall
What color will gram positive bacteria stain? - Answers Purple
What color will gram negative bacteria stain? - Answers Pink
Gram negative bacteria has a ________ ________________ ______ _______. - Answers Thin
peptidoglycan cell wall
What is a differential stain? - Answers The use of two or more dyes that react differently with different
kinds/parts of bacteria.
What are two types of cell fixation? - Answers Heat fixation and chemical fixation
What does the Giemsa stain detect? - Answers Blood parasites
True or false: Negative staining stains only the microorganism - Answers False. Negative staining stains
everything BUT the microorganism
, Giemsa stain: what colors does the nucleus and cytoplasm stain? - Answers Nucleus: bluish purple
Cytoplasm: pink
What type of cell does the Giemsa stain? - Answers White blood cells
What type of samples are acid-fast stains often performed on? - Answers Sputum samples (thick mucus
produced in lungs that can be coughed up)
The naked eye can see up to ______ micrometers. - Answers 100 micrometers
Cellular organelles can be as small as ______ micrometers. - Answers 0.2 micrometers
Does phase contrast need staining? - Answers No
What is the difference between phase contrast compared to brightfield? - Answers You are able to
visualize things that would otherwise be invisible; cells are highly distinguishable
What type of microscopy uses lasers? - Answers Confocal
Does electron microscopy use fixation? - Answers Yes
Does electron microscopy use live or dead samples? - Answers Dead
What type of secondary (counterstain) dye called in gram staining? - Answers Safranin
___________________ ______________ microscopy coats samples with gold of platinum. - Answers
Scanning electron microscopy
Does negative staining kill the organism and why? - Answers No. Since negative staining is mildly
invasive, it may not kill the microorganism.
Who is the father of medicine? - Answers Hippocrates
What is microscopy? - Answers Use of light or electrons to magnify objects
What are the two measurements of microscopy? - Answers Micrometer and nanometer
Magnification - Answers Increase the size of object
True or false: Shorter wave lengths increase resolving power. - Answers True
Light microscope - Answers It uses visible light and blue wave lengths for improved resolution.
What is the magnification and resolution of a light microscope? - Answers Magnification: 1x-2000x
Resolution: 10mm-200mm
What are light microscopes used to see? - Answers Whole cells and organelles
