week11 : microbiology of animals Flashcards
The pathogenicity is the ability to ___ the host
damage
T or F : the normal microbiome contains opportunistic pathogens
t
What is a opportunistic pathogen?
a pathogen that causes disease only in the absence of normal host resistance
What is the rumen?
the foregut fermentation chamber
T or F : the rumen is an aerobic environement
false it is anaerobic
how is maintained the pH of the rumen?
by the sodium bicarbonate and the sodium phopsphate of the saliva
What are the products of the fermentation in the rumen?
volatile FA (acetic, propionic and butyric), CH4 and CO2.
t or f : the FA produced by fermentation in the rumen can pass through the wall and be utilized by the animal
t
the ruminococcacea are within the category of the ___
furmicute
t or f : the three domain are found in the rumen
true, protozoa, archae and bacteria
What are the three principal organisms found in the rumen?
firmicutes, bacterioidetes and eukrysrchaeota
Firmicutes are gram ___
+
bacteroidetes are gram ___
-
T or F :the methanogens are eukaryotes
false they are euryarchaeoata
Why do we want to inhibit the methanogenesis with monensin?
because the acetate produced in the rumen could be used as energy by the cow. However, the methanogens transform the acetate into CH4 (loss of energy from feed).
what is the role of the omasum?
to let go of collect the excess water
What is the name of the stomach in the ruminants?
abomasum
T or F : herbivores are ruminant
false, there is non-ruminant herbivores
T or F : the hindgut fermenters have a higher dietary requirement for amino acids and vitamins than the ruminants
true
the symbiose example between the _____ bacteria and the ____ is a good example of how symbioses are established
aliivibrio fischeri and the hawain bobtail squid
What are the two microorganissm found in the termites that can be found in ruminants
bacteriodetes and the firmicutes
termites are foregut or hindgut fermenters
hindgut
what is the microorganism that is found in the termites and not found in the ruminants
the spirochette
at birth the microbiome of humans is mostly composed of ____
firmicutes
when food is introduced after birth the ____ are introduced in the microbiome
bacteroidetes
at 6 days of age, the microbiome is composed of ___ and ___
firmicutes and proteobacteria
when is the microbiome the least stable
during infancy
when is the microbiome the more stable
during adulthood
the species that colonize the ducts of the skin are gram ____
+
what is the compound secreted by the normal microbiome of the skin
bacteriocin
propiobobacterium acnes is a ____ aerobe or anaerobe
anaerobe aerotolerant that inhabit the hair canal
what are the domain of microorganisms that live on the skin
yeats, molds and bacteria
T or F : the microbiome of the skin contains archae
false
the microflora of the skin is mostly composed of gram___
+
What are the most common microorganism found in the microflora of the skin
firmicutes and actinobacteia
what are the common gram negative found in the microflora of the skin
bacteriodetes and proteobacteria
what is one of the microorganism causing dental plaque*****
streptococcus mutans
how does the streptococcus mutans attached to the tooth surface
by synthesis of dextran (extracell polysaccharide)
how are cavities produced**
by the fermentation of sucrose into lactic acid that solubilise the tooth enamel
are streptococcus mutans able to ferment sucrose
yes
T or F : in the human colon there is only anaerobes
false, there is also facultative aerobes
what are the two most common microorganism in the colon of humans
bacteriodetes and firmicutes
what is the microorganism found in ruminant and not in the colon of humans?
eukaryoarchaeota
T or F : the microorganisms in the colon can digest cellulose
true
what are the two amino acid used by sulfate reducers to produce hydrogen sulfide
methionine and cysteine
what is responsible for the smell in the colon
the methanethiol produced by sulfate reducers
lean mices have more ___ while obese mice have more ___
lean –> methanogens
obese –> bacteroidetes
**T or F : the lower respiratory tract is sterile
false, but is as a low biomass
what are the three potential pathogens foound in the nasopharynx
- streptococcus pneumoniae
- haemophilus influenzae
- neisseria meningitidis
What are the two microorganisms of the gastrointestinal tract that can cause urinary infections
e coli
proteus mirabillis
what is the normal pH of the vagina of a sexually mature women
acidic (4.5)
**why is the pH of the sexually mature women acidic
because of the lactobacilli degrading the glycogen produced by hormones
what is the yeast found in the vagina
candida albicans