Bio 156 - Lab Final (Practical) || with Validated Solutions.
1. genetics
2. dental hygiene habits
3. diet (sucrose consumption)
4. numbers of acid producing bacteria in the mouth (Lactobacilli) correct answers What are the
four factors that determine a person's susceptibility to dental carries?
test for the number of oral-acid producing bacteria correct answers In lab we cannot test for
genetic make up, dental hygiene habits or diet, but we will ___
caries correct answers studies have indicated a correlation between high numbers of oral
Lactobacilli and an increased susceptibility to ___
Snyder Caries Test correct answers the ___ is performed to determine susceptibility to caries, not
whether or not a person has cavities
qualitative; quantitative correct answers the snyder caries test will involve a ___ test for numbers
of lactobacilli, a ___ determination of lactobacilli will not be done
glucose; bromcresol green correct answers snyder medium contains 2 key ingredients, ___ and
the pH indicator ___.
glucose correct answers ___ is in the snyder medium to serve as a source of food
lactobacillus correct answers ___ in the snyder medium will ferment glucose producing acid,
resulting in the pH of the medium decreasing
yellow correct answers bromcresol green is green at basic pH, but turns ___ in the presence of
acid.
fast correct answers in the snyder carie test, lactobacillus numbers will be estimated by how ___
the medium turns yellow
marked correct answers please indicate the caries susceptibility for the following:
medium turns yellow in:
24 Hr 48Hr 72 Hr
+
moderate correct answers please indicate the caries susceptibility for the following:
medium turns yellow in:
24 Hr 48Hr 72 Hr
-+
,slight correct answers please indicate the caries susceptibility for the following:
medium turns yellow in:
24 Hr 48Hr 72 Hr
--+
negative correct answers please indicate the caries susceptibility for the following:
medium turns yellow in:
24 Hr 48Hr 72 Hr
---
Negative; the medium did not turn yellow, meaning there was no acid present. acid keeps our pH
level where candida (thrush) can't survive correct answers one person has "marked"
susceptibility to caries the other has a "negative" result. both people are put on high doses of
antibiotics. which person will have a greater risk of developing thrush?
psychrophiles correct answers -optimal growth temperature between -5C and 20C.
-these bacteria will be found in the arctic ice and in antartical
-in MI they will be found on snow, and in very cold water; ex. lake superior
mesophiles correct answers -optimal growth temperature between 20C and 50C.
-most pathogens fall in this class (since most grown between 35C and 40C)
-body temp: 37C
thermophiles correct answers -optimal growth between 50 and 80C
-bacteria in this group occur in soil where the midday temperature reaches greater than 50C or in
compost piles where fermentation activity can cause temperatures to exceed 60 and 65C
-heat loving
hyperthermophiles correct answers -growth optimum above 80C
-there are many bacteria that occupy environments that are heated by volcanic activity where
water is super heated to above 100C
-these bacteria have been isolated from thermal vents deep within the ocean floor and from
volcanic heated hot springs
psychrotrophs correct answers -these microbes can grow both at mesophilic and psychrophilic
temperature ranges
-most are nonpathogens that grow faster at the mesophilic temperature range
-primarily associated with the spoilage of refrigerated food, but a few species are pathogenic
-these pathogens, which include, include Listeria monocytogenes and Yersinia enterocolitica,
grow faster at the psychrophilic temperature ranges
Psychrophiles correct answers Please indicate the microbial species
(+ growth - no growth)
Temp C 5 25 37 45 55
, +----
Mesophiles correct answers Please indicate the microbial species
(+ growth - no growth)
Temp C 5 25 37 45 55
- + + +/- -
Thermophiles correct answers Please indicate the microbial species
(+ growth - no growth)
Temp C 5 25 37 45 55
---++
Hyper-thermophiles correct answers Please indicate the microbial species
(+ growth - no growth)
Temp C 5 25 37 45 55
----+
Psychotrophs correct answers Please indicate the microbial species
(+ growth - no growth)
Temp C 5 25 37 45 55
+++--
aerobic correct answers ___ slant: no stab; streak surface only
broth correct answers in test tubes with ___, the dip, twist and lift method is used
anaerobic correct answers ___ slant: stab bottom, streak slant
acidic correct answers the pH values ranging from 0 to almost 7.0 are called:
neutral correct answers a pH of 7.0 is called:
alkaline or basic correct answers the pH values slightly greater than 7.0 and up to 14 are called
___
acidophiles correct answers grow best in acidic pH
neutrophiles correct answers grow best around neutral pH
basophiles (alkalinophile) correct answers grow best at basic pH
acidophile correct answers please indicate the microbial species based off of their optimum pH
(+ growth - no growth)
pH 3 5 7 9 12
+ +/- - - -
1. genetics
2. dental hygiene habits
3. diet (sucrose consumption)
4. numbers of acid producing bacteria in the mouth (Lactobacilli) correct answers What are the
four factors that determine a person's susceptibility to dental carries?
test for the number of oral-acid producing bacteria correct answers In lab we cannot test for
genetic make up, dental hygiene habits or diet, but we will ___
caries correct answers studies have indicated a correlation between high numbers of oral
Lactobacilli and an increased susceptibility to ___
Snyder Caries Test correct answers the ___ is performed to determine susceptibility to caries, not
whether or not a person has cavities
qualitative; quantitative correct answers the snyder caries test will involve a ___ test for numbers
of lactobacilli, a ___ determination of lactobacilli will not be done
glucose; bromcresol green correct answers snyder medium contains 2 key ingredients, ___ and
the pH indicator ___.
glucose correct answers ___ is in the snyder medium to serve as a source of food
lactobacillus correct answers ___ in the snyder medium will ferment glucose producing acid,
resulting in the pH of the medium decreasing
yellow correct answers bromcresol green is green at basic pH, but turns ___ in the presence of
acid.
fast correct answers in the snyder carie test, lactobacillus numbers will be estimated by how ___
the medium turns yellow
marked correct answers please indicate the caries susceptibility for the following:
medium turns yellow in:
24 Hr 48Hr 72 Hr
+
moderate correct answers please indicate the caries susceptibility for the following:
medium turns yellow in:
24 Hr 48Hr 72 Hr
-+
,slight correct answers please indicate the caries susceptibility for the following:
medium turns yellow in:
24 Hr 48Hr 72 Hr
--+
negative correct answers please indicate the caries susceptibility for the following:
medium turns yellow in:
24 Hr 48Hr 72 Hr
---
Negative; the medium did not turn yellow, meaning there was no acid present. acid keeps our pH
level where candida (thrush) can't survive correct answers one person has "marked"
susceptibility to caries the other has a "negative" result. both people are put on high doses of
antibiotics. which person will have a greater risk of developing thrush?
psychrophiles correct answers -optimal growth temperature between -5C and 20C.
-these bacteria will be found in the arctic ice and in antartical
-in MI they will be found on snow, and in very cold water; ex. lake superior
mesophiles correct answers -optimal growth temperature between 20C and 50C.
-most pathogens fall in this class (since most grown between 35C and 40C)
-body temp: 37C
thermophiles correct answers -optimal growth between 50 and 80C
-bacteria in this group occur in soil where the midday temperature reaches greater than 50C or in
compost piles where fermentation activity can cause temperatures to exceed 60 and 65C
-heat loving
hyperthermophiles correct answers -growth optimum above 80C
-there are many bacteria that occupy environments that are heated by volcanic activity where
water is super heated to above 100C
-these bacteria have been isolated from thermal vents deep within the ocean floor and from
volcanic heated hot springs
psychrotrophs correct answers -these microbes can grow both at mesophilic and psychrophilic
temperature ranges
-most are nonpathogens that grow faster at the mesophilic temperature range
-primarily associated with the spoilage of refrigerated food, but a few species are pathogenic
-these pathogens, which include, include Listeria monocytogenes and Yersinia enterocolitica,
grow faster at the psychrophilic temperature ranges
Psychrophiles correct answers Please indicate the microbial species
(+ growth - no growth)
Temp C 5 25 37 45 55
, +----
Mesophiles correct answers Please indicate the microbial species
(+ growth - no growth)
Temp C 5 25 37 45 55
- + + +/- -
Thermophiles correct answers Please indicate the microbial species
(+ growth - no growth)
Temp C 5 25 37 45 55
---++
Hyper-thermophiles correct answers Please indicate the microbial species
(+ growth - no growth)
Temp C 5 25 37 45 55
----+
Psychotrophs correct answers Please indicate the microbial species
(+ growth - no growth)
Temp C 5 25 37 45 55
+++--
aerobic correct answers ___ slant: no stab; streak surface only
broth correct answers in test tubes with ___, the dip, twist and lift method is used
anaerobic correct answers ___ slant: stab bottom, streak slant
acidic correct answers the pH values ranging from 0 to almost 7.0 are called:
neutral correct answers a pH of 7.0 is called:
alkaline or basic correct answers the pH values slightly greater than 7.0 and up to 14 are called
___
acidophiles correct answers grow best in acidic pH
neutrophiles correct answers grow best around neutral pH
basophiles (alkalinophile) correct answers grow best at basic pH
acidophile correct answers please indicate the microbial species based off of their optimum pH
(+ growth - no growth)
pH 3 5 7 9 12
+ +/- - - -
