BIO 2104 Lab Practical Final Exam Questions and Answers Solved Correctly
course adjustment knob - Answers Moves the stage up and down for focusing
fine adjustment knob - Answers Fine tunes the focus and increases the detail of the specimen.
oil immersion lens (100x) - Answers only lens that uses oil
labeling plates - Answers -Label bottom (agar side) of the plate
- Do not label lid
-Plates should be inverted when incubating
streak plate technique - Answers a technique which produces isolated colonies of an organism
gram positive stain - Answers retain crystal violet and stain purple, thick peptidoglycan cell wall
gram negative stain - Answers pink or red, thin peptidoglycan and outer membrane
endospore stain - Answers Used to distinguish endospores from vegetative cells. Endospores appear
green
capsule staining - Answers Negative stain - capsules colorless against a stained background
acid fast stain - Answers Acid fastness is a physical property that gives a bacterium the ability to resist
decolorization by acids during staining procedures. used to detect TB and mycobacterium
acid fast bacteria - Answers Retain the primary stain even when treated with acid alcohol. (pink)
serial dilution - Answers Dilution of a substance several times by the same amount each time to produce
a countable (between 30 and 300 colonies)
Microbial oxygen requirements - Answers •Aerobe - Can use oxygen for metabolism and possesses
enzymes to break down toxic oxygen
-Obligate aerobe- Cannot grow without oxygen
•Facultative anaerobe - Can use oxygen for metabolism if it's available, but can also grow without it
•Microaerophile - Doesn't grow at normal atmospheric oxygen levels, but does require a small amount
of it
•Anaerobe- lacks metabolic enzyme systems for using oxygen during metabolism.
-Obligate anaerobe - also lack the enzymes to detoxify oxygen
-Aerotolerant anaerobe - has enzymes to detoxify oxygen
, optimal temperature - Answers temperature at which microbe grows best
minimum temperature - Answers lowest temperature that permits a microbe's growth and metabolism
maximum temperature - Answers the highest temperature at which growth and metabolism can
proceed before proteins are denatured
Isotonic - Answers Describes a solution whose solute concentration is equal to the solute concentration
inside a cell
Hypotonic - Answers Referring to a solution that, when surrounding a cell, will cause the cell to take up
water.
Hypertonic - Answers (of a solution) having a higher osmotic pressure than a comparison solution
bacterial transformation - Answers ability of bacteria to alter their genetic makeup by uptaking foreign
DNA from another bacterial cell and incorporating it into their own. Type of horizontal gene transfer.
bacterial competence - Answers Ability of bacteria to uptake extracellular DNA
cloning vector - Answers a DNA molecule that can carry foreign DNA into a host cell and replicate there.
Plasmid is most common vector
pGLO plasmid - Answers carries the GFP gene for fluorescent green,
gives the bacteria resistance to an antibiotic (ampicillin)
PCR (polymerase chain reaction) - Answers A laboratory technique for amplifying DNA in vitro by
incubating with special primers, DNA polymerase molecules, and nucleotides.
Denaturation - Heating to 95°C is used to break the hydrogen bonds between nitrogenous bases and
separate the strands of DNA.
Priming - After cooling, the primers attach to their complementary sites on the separated DNA strands.
Extension - The sample is warmed back up to 72°C and the polymerase begins synthesizing new strands
starting at the primers.
Kirby-Bauer method (antibiotic sensitivity) - Answers used to determine the sensitivity or resistance of a
bacterium to an antimicrobial
zone of inhibition - Answers The zone where bacteria can't grow around a given antibiotic. The larger
the zone, the better the antibiotic works against the given microbe.
Effect of UV light on microbes - Answers causes thymine dimers (abnormal bonds in double helix that
can interfere with DNA replication, which can cause death to the cell)
course adjustment knob - Answers Moves the stage up and down for focusing
fine adjustment knob - Answers Fine tunes the focus and increases the detail of the specimen.
oil immersion lens (100x) - Answers only lens that uses oil
labeling plates - Answers -Label bottom (agar side) of the plate
- Do not label lid
-Plates should be inverted when incubating
streak plate technique - Answers a technique which produces isolated colonies of an organism
gram positive stain - Answers retain crystal violet and stain purple, thick peptidoglycan cell wall
gram negative stain - Answers pink or red, thin peptidoglycan and outer membrane
endospore stain - Answers Used to distinguish endospores from vegetative cells. Endospores appear
green
capsule staining - Answers Negative stain - capsules colorless against a stained background
acid fast stain - Answers Acid fastness is a physical property that gives a bacterium the ability to resist
decolorization by acids during staining procedures. used to detect TB and mycobacterium
acid fast bacteria - Answers Retain the primary stain even when treated with acid alcohol. (pink)
serial dilution - Answers Dilution of a substance several times by the same amount each time to produce
a countable (between 30 and 300 colonies)
Microbial oxygen requirements - Answers •Aerobe - Can use oxygen for metabolism and possesses
enzymes to break down toxic oxygen
-Obligate aerobe- Cannot grow without oxygen
•Facultative anaerobe - Can use oxygen for metabolism if it's available, but can also grow without it
•Microaerophile - Doesn't grow at normal atmospheric oxygen levels, but does require a small amount
of it
•Anaerobe- lacks metabolic enzyme systems for using oxygen during metabolism.
-Obligate anaerobe - also lack the enzymes to detoxify oxygen
-Aerotolerant anaerobe - has enzymes to detoxify oxygen
, optimal temperature - Answers temperature at which microbe grows best
minimum temperature - Answers lowest temperature that permits a microbe's growth and metabolism
maximum temperature - Answers the highest temperature at which growth and metabolism can
proceed before proteins are denatured
Isotonic - Answers Describes a solution whose solute concentration is equal to the solute concentration
inside a cell
Hypotonic - Answers Referring to a solution that, when surrounding a cell, will cause the cell to take up
water.
Hypertonic - Answers (of a solution) having a higher osmotic pressure than a comparison solution
bacterial transformation - Answers ability of bacteria to alter their genetic makeup by uptaking foreign
DNA from another bacterial cell and incorporating it into their own. Type of horizontal gene transfer.
bacterial competence - Answers Ability of bacteria to uptake extracellular DNA
cloning vector - Answers a DNA molecule that can carry foreign DNA into a host cell and replicate there.
Plasmid is most common vector
pGLO plasmid - Answers carries the GFP gene for fluorescent green,
gives the bacteria resistance to an antibiotic (ampicillin)
PCR (polymerase chain reaction) - Answers A laboratory technique for amplifying DNA in vitro by
incubating with special primers, DNA polymerase molecules, and nucleotides.
Denaturation - Heating to 95°C is used to break the hydrogen bonds between nitrogenous bases and
separate the strands of DNA.
Priming - After cooling, the primers attach to their complementary sites on the separated DNA strands.
Extension - The sample is warmed back up to 72°C and the polymerase begins synthesizing new strands
starting at the primers.
Kirby-Bauer method (antibiotic sensitivity) - Answers used to determine the sensitivity or resistance of a
bacterium to an antimicrobial
zone of inhibition - Answers The zone where bacteria can't grow around a given antibiotic. The larger
the zone, the better the antibiotic works against the given microbe.
Effect of UV light on microbes - Answers causes thymine dimers (abnormal bonds in double helix that
can interfere with DNA replication, which can cause death to the cell)
