1
BSC 203 Exam 1 Questions with Answers (100% Correct
Answers)
uses visible light to illuminate specimen. Also allows us to magnify
cells up to 1000 times and to resolve details that are very tiny(0.2 um)
Answer: light microscope
What are the three things required for viewing cells in a light
microscope? Answer: 1)A bright light must be focused onto the
specimen by lenses in the condenser
2)The specimen must be carefully prepared to allow light to pass
through it
3)Set of lenses must be arranged to focus an image of the specimen in
the eye
-uses a beam of electrons instead of a beam of light and magnetic coils
to focus the beam instead of glass lenses.
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,2
- specimen is stained with electron-dense heavy metals that absorb or
scatter electrons,
-Can resolve details as small as about 1nm in biological specimens
Answer: transmission electron microscope
-special type of fluorescence microscope that builds up an image by
scanning the specimen with a laser beam
-the beam is focused onto a single point at a specific depth in the
specimen, and a pinhole in the detector allows only fluorescence
emitted from this same point to be included in the image
-provides an optical section showing the individual cells clearly
Answer: confocal microscopy
-Specimen is coated with a very thin film of a heavy metal
-is scanned by a beam of electrons brought to a focus on the specimen
by magnetic coils that act as lenses
-microscope creates three-dimensional objects with great depth of
focus and can resolve details down between 3 nm and 20 nm Answer:
scanning electron microscopy
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,3
-fluorescence dyes are used for staining cells and are detected
-illuminating light is passed through two filters
-1st filters the light before it reaches the specimen, passing only those
wavelengths that excite the dye
2nd blocks out this light and passes only those wavelengths emitted
when the dye fluoresces. Dyed objects show up in bright color on a
dark background Answer: fluorescence microscope
What are the four points of cell theory? Answer: 1. The smallest clearly
defined unit of life is the cell (Schwann)
2. All living organisms are composed of cells. (Schwann)
3. Cells arise only from other cells (Virchow)
4. Each cell can maintain its living properties independently from the
rest, but the properties of life displayed by any organism depend on
the properties of the cells its made of. (Virchow)
What are the characteristics of a prokaryotic cell? Answer: -
bacteria(one of the two divisions of prokaryotes)
-lack a nucleus
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, 4
-spherical, rod like, or corkscrew
-small
-most diverse
-single celled
-can live in any habitat
-use binary fission
-circular DNA
-don't have membrane bound organelles
What are the characteristics of a eukaryotic cell? Answer: -bigger and
more elaborate
-ex: amoeba and yeasts (single celled)
-nucleus
-mitochondria
-chloroplasts
-cytoskeleton
© 2025 All rights reserved
BSC 203 Exam 1 Questions with Answers (100% Correct
Answers)
uses visible light to illuminate specimen. Also allows us to magnify
cells up to 1000 times and to resolve details that are very tiny(0.2 um)
Answer: light microscope
What are the three things required for viewing cells in a light
microscope? Answer: 1)A bright light must be focused onto the
specimen by lenses in the condenser
2)The specimen must be carefully prepared to allow light to pass
through it
3)Set of lenses must be arranged to focus an image of the specimen in
the eye
-uses a beam of electrons instead of a beam of light and magnetic coils
to focus the beam instead of glass lenses.
© 2025 All rights reserved
,2
- specimen is stained with electron-dense heavy metals that absorb or
scatter electrons,
-Can resolve details as small as about 1nm in biological specimens
Answer: transmission electron microscope
-special type of fluorescence microscope that builds up an image by
scanning the specimen with a laser beam
-the beam is focused onto a single point at a specific depth in the
specimen, and a pinhole in the detector allows only fluorescence
emitted from this same point to be included in the image
-provides an optical section showing the individual cells clearly
Answer: confocal microscopy
-Specimen is coated with a very thin film of a heavy metal
-is scanned by a beam of electrons brought to a focus on the specimen
by magnetic coils that act as lenses
-microscope creates three-dimensional objects with great depth of
focus and can resolve details down between 3 nm and 20 nm Answer:
scanning electron microscopy
© 2025 All rights reserved
,3
-fluorescence dyes are used for staining cells and are detected
-illuminating light is passed through two filters
-1st filters the light before it reaches the specimen, passing only those
wavelengths that excite the dye
2nd blocks out this light and passes only those wavelengths emitted
when the dye fluoresces. Dyed objects show up in bright color on a
dark background Answer: fluorescence microscope
What are the four points of cell theory? Answer: 1. The smallest clearly
defined unit of life is the cell (Schwann)
2. All living organisms are composed of cells. (Schwann)
3. Cells arise only from other cells (Virchow)
4. Each cell can maintain its living properties independently from the
rest, but the properties of life displayed by any organism depend on
the properties of the cells its made of. (Virchow)
What are the characteristics of a prokaryotic cell? Answer: -
bacteria(one of the two divisions of prokaryotes)
-lack a nucleus
© 2025 All rights reserved
, 4
-spherical, rod like, or corkscrew
-small
-most diverse
-single celled
-can live in any habitat
-use binary fission
-circular DNA
-don't have membrane bound organelles
What are the characteristics of a eukaryotic cell? Answer: -bigger and
more elaborate
-ex: amoeba and yeasts (single celled)
-nucleus
-mitochondria
-chloroplasts
-cytoskeleton
© 2025 All rights reserved
