BIOL 2420 NEWEST EXAM 1 VERSIONS
COMPLETE EXAM QUESTIONS WITH
DETAILED VERIFIED ANSWERS (100%
GUARANTEED PASS) || A+ GRADED
1. Archaea - ANSWER ✓ Prokaryotic organisms with cell walls that lack
peptidoglycan (if they have them); found in extreme environments;
3 Main Groups:
-Methanogens
-Extreme Halophiles
-Extreme Thermophiles
Do not cause disease in humans
2. Brightfield Illumination - ANSWER ✓ brightly illuminated field of vision
that is focused by the condenser; used when you can stain a specimin
3. Darkfield Microscope - ANSWER ✓ used to examine live microorganisms
that are either invisible in ordinary light microscope or cannot be stained or
cannot view characteristics if stained; uses a darkfield condenser that
contains an opaque disc that only directs light that is reflected off the
specimen to enter the objective lens; used to examine very thin spirochetes
4. Phase-Contrast Microscope - ANSWER ✓ internal structures of a cell
become more sharply defined; isn't necessary to fix or stain the specimen;
image created by both direct and reflected rays
5. Differential Interference Contrast Microscopy - ANSWER ✓ similar to
phase-contrast but uses two beams of light to add contrasting colors to
specimen; higher resolution than standard phase-contrast; brightly colored &
almost 3D image
6. Fluorescence Microscopy - ANSWER ✓ takes advantage of fluorescence;
some organisms naturally fluoresce others can be stained with
fluorochromes to fluoresce; uses ultraviolet light; image is a bright object
against a dark background
, 7. Electron Microscopy - ANSWER ✓ beam of electrons is used instead of
light to examine really small structures & viruses; great resolution is caused
by short wavelength of electrons; images are black & white
8. Trasmission Electron Microscopy - ANSWER ✓ beam of electrons passes
through a ultrathin section of a specimen; specimens can be stained with
heavy metal salts for contrasts; 10,000X-100,000X magnification; useful for
examining layers of a specimen
9. Scanning Electron Microscopy - ANSWER ✓ electron beam directed over
the surface of a specimen; useful for studying surface structures of intact
cells & viruses; 1,000 to 10,000X magnification
10.Microbes - ANSWER ✓ minute living things that are too small to be seen
with the unaided eye; include bacteria, fungi, protozoa, microscopic algae,
and viruses
11.Benefits of Microogranisms - ANSWER ✓ basis of food chains in marine &
freshwater environments; decomposers; important role in photosynthesis;
digestion in human intestine; synthesis of Vitamin B and Vitamin K;
synthesize food & alcohol
12.Pathogenic - ANSWER ✓ disease producing
13.Bacteria - ANSWER ✓ Unicellular prokaryotic organisms; enclosed in cell
walls composed of peptidoglycan; generally reproduce by binary fission;
swim using flagella
14.Methanogens - ANSWER ✓ type of Archaea that produce methane as a
waste product from respiration
15.Extreme Halophiles - ANSWER ✓ type of Archaea that live in extremely
salty environments
16.Extreme Thermophiles - ANSWER ✓ type of Archaea that live in hot
sulfurous water
COMPLETE EXAM QUESTIONS WITH
DETAILED VERIFIED ANSWERS (100%
GUARANTEED PASS) || A+ GRADED
1. Archaea - ANSWER ✓ Prokaryotic organisms with cell walls that lack
peptidoglycan (if they have them); found in extreme environments;
3 Main Groups:
-Methanogens
-Extreme Halophiles
-Extreme Thermophiles
Do not cause disease in humans
2. Brightfield Illumination - ANSWER ✓ brightly illuminated field of vision
that is focused by the condenser; used when you can stain a specimin
3. Darkfield Microscope - ANSWER ✓ used to examine live microorganisms
that are either invisible in ordinary light microscope or cannot be stained or
cannot view characteristics if stained; uses a darkfield condenser that
contains an opaque disc that only directs light that is reflected off the
specimen to enter the objective lens; used to examine very thin spirochetes
4. Phase-Contrast Microscope - ANSWER ✓ internal structures of a cell
become more sharply defined; isn't necessary to fix or stain the specimen;
image created by both direct and reflected rays
5. Differential Interference Contrast Microscopy - ANSWER ✓ similar to
phase-contrast but uses two beams of light to add contrasting colors to
specimen; higher resolution than standard phase-contrast; brightly colored &
almost 3D image
6. Fluorescence Microscopy - ANSWER ✓ takes advantage of fluorescence;
some organisms naturally fluoresce others can be stained with
fluorochromes to fluoresce; uses ultraviolet light; image is a bright object
against a dark background
, 7. Electron Microscopy - ANSWER ✓ beam of electrons is used instead of
light to examine really small structures & viruses; great resolution is caused
by short wavelength of electrons; images are black & white
8. Trasmission Electron Microscopy - ANSWER ✓ beam of electrons passes
through a ultrathin section of a specimen; specimens can be stained with
heavy metal salts for contrasts; 10,000X-100,000X magnification; useful for
examining layers of a specimen
9. Scanning Electron Microscopy - ANSWER ✓ electron beam directed over
the surface of a specimen; useful for studying surface structures of intact
cells & viruses; 1,000 to 10,000X magnification
10.Microbes - ANSWER ✓ minute living things that are too small to be seen
with the unaided eye; include bacteria, fungi, protozoa, microscopic algae,
and viruses
11.Benefits of Microogranisms - ANSWER ✓ basis of food chains in marine &
freshwater environments; decomposers; important role in photosynthesis;
digestion in human intestine; synthesis of Vitamin B and Vitamin K;
synthesize food & alcohol
12.Pathogenic - ANSWER ✓ disease producing
13.Bacteria - ANSWER ✓ Unicellular prokaryotic organisms; enclosed in cell
walls composed of peptidoglycan; generally reproduce by binary fission;
swim using flagella
14.Methanogens - ANSWER ✓ type of Archaea that produce methane as a
waste product from respiration
15.Extreme Halophiles - ANSWER ✓ type of Archaea that live in extremely
salty environments
16.Extreme Thermophiles - ANSWER ✓ type of Archaea that live in hot
sulfurous water
