Probiotics MCB6424 Exam 3
Questions And Answers
/.Microbiota - Answer-✅The microorganisms (commensal, symbiotic, and pathogenic)
that live in an established environment
/.Microbiome - Answer-✅The full complement of microbes, their genes, and genomes in
a particular environment
/.200 - Answer-✅The gut microbiome contains ___ trillion cells
/.10 - Answer-✅The gut microbiome has __ times the number of human cells
/.150 - Answer-✅The gut microbiome is ___ times larger than the human genome
/.Colon (10^11-10^12 cfu/mL) - Answer-✅Which part of the GI tract has the highest
density of microbiota?
/.Stomach and duodenum (10-10^3 cfu/mL) - Answer-✅Which part of the GI tract has
the lowest density of microbiota?
/.True - Answer-✅T/F: the gut microbiota is generally non-pathogenic
/.1-3% - Answer-✅The gut microbiota is __% of our total body mass
/.True (this concept is has changed recently) - Answer-✅T/F: humans and animals are
usually germfree in utero
/.Normal microbiota - Answer-✅The type of microbiota that establish permanent
colonies inside/on the body without producing disease; ex: Staphylococcus
(skin/mucous membranes) and E. coli (colon); live in symbiosis with the host
/.Transient microbiota - Answer-✅The type of microbiota that are present for various
periods of time and then disappear because the host's defenses don't allow them to
become permanent
, /.Symbiosis - Answer-✅The long-term interaction between 2+ different biological
species; "living together;" 3 types: commensalism, mutualism, and parasitism
/.Commensalism - Answer-✅The type of symbiosis in which one organism benefits and
the other is unaffected
/.Mycobacteria (in the ear) - Answer-✅What is an example of commensalism?
/.Mutualism - Answer-✅The type of symbiosis in which both organisms benefit from
living together
/.E. coli (synthesize vitamin K in the colon) - Answer-✅What is an example of
mutualism?
/.Parasitism - Answer-✅The type of symbiosis in which one organisms benefits at the
expense of the other by causing harm/damage
/.Any pathogenic bacteria in the body - Answer-✅What is an example of parasitism?
/.Oppostunistic pathogen - Answer-✅Which type of pathogen only causes disease
under special circumstances (and normally are not harmful in their natural
environment)?
/.S. pneumoniae and E. coli - Answer-✅What are 2 examples of opportunistic
pathogens?
/.IgA and GALT - Answer-✅The complete absence of bacteria in the gut (mice models)
resulted in very low/defective levels of which 2 things?
/.Butyrate - Answer-✅Which metabolite is used as energy for gut epithelial cells, lowers
mucosal inflammation, and strengthens epithelial barrier function?
/.Acetate and propionate - Answer-✅Which 2 metabolites are used for lipogenesis and
gluconeogenesis in the host's gut?
/.10 million - Answer-✅How many prokaryotic species are there estimated to be?
/.Operational taxonomic unit (OTU) - Answer-✅A term used to categorize bacteria
based on sequence similarity (97% rRNA gene sequence identity)
/.16S-based approach - Answer-✅The type of method for studying microbiota in which
the gut microbiota DNA is extracted, the 16S rRNA is amplified/sequenced, grouped
into OTUs, identified based on phylogeny, and further identified based on sequence
databases (BLAST)
Questions And Answers
/.Microbiota - Answer-✅The microorganisms (commensal, symbiotic, and pathogenic)
that live in an established environment
/.Microbiome - Answer-✅The full complement of microbes, their genes, and genomes in
a particular environment
/.200 - Answer-✅The gut microbiome contains ___ trillion cells
/.10 - Answer-✅The gut microbiome has __ times the number of human cells
/.150 - Answer-✅The gut microbiome is ___ times larger than the human genome
/.Colon (10^11-10^12 cfu/mL) - Answer-✅Which part of the GI tract has the highest
density of microbiota?
/.Stomach and duodenum (10-10^3 cfu/mL) - Answer-✅Which part of the GI tract has
the lowest density of microbiota?
/.True - Answer-✅T/F: the gut microbiota is generally non-pathogenic
/.1-3% - Answer-✅The gut microbiota is __% of our total body mass
/.True (this concept is has changed recently) - Answer-✅T/F: humans and animals are
usually germfree in utero
/.Normal microbiota - Answer-✅The type of microbiota that establish permanent
colonies inside/on the body without producing disease; ex: Staphylococcus
(skin/mucous membranes) and E. coli (colon); live in symbiosis with the host
/.Transient microbiota - Answer-✅The type of microbiota that are present for various
periods of time and then disappear because the host's defenses don't allow them to
become permanent
, /.Symbiosis - Answer-✅The long-term interaction between 2+ different biological
species; "living together;" 3 types: commensalism, mutualism, and parasitism
/.Commensalism - Answer-✅The type of symbiosis in which one organism benefits and
the other is unaffected
/.Mycobacteria (in the ear) - Answer-✅What is an example of commensalism?
/.Mutualism - Answer-✅The type of symbiosis in which both organisms benefit from
living together
/.E. coli (synthesize vitamin K in the colon) - Answer-✅What is an example of
mutualism?
/.Parasitism - Answer-✅The type of symbiosis in which one organisms benefits at the
expense of the other by causing harm/damage
/.Any pathogenic bacteria in the body - Answer-✅What is an example of parasitism?
/.Oppostunistic pathogen - Answer-✅Which type of pathogen only causes disease
under special circumstances (and normally are not harmful in their natural
environment)?
/.S. pneumoniae and E. coli - Answer-✅What are 2 examples of opportunistic
pathogens?
/.IgA and GALT - Answer-✅The complete absence of bacteria in the gut (mice models)
resulted in very low/defective levels of which 2 things?
/.Butyrate - Answer-✅Which metabolite is used as energy for gut epithelial cells, lowers
mucosal inflammation, and strengthens epithelial barrier function?
/.Acetate and propionate - Answer-✅Which 2 metabolites are used for lipogenesis and
gluconeogenesis in the host's gut?
/.10 million - Answer-✅How many prokaryotic species are there estimated to be?
/.Operational taxonomic unit (OTU) - Answer-✅A term used to categorize bacteria
based on sequence similarity (97% rRNA gene sequence identity)
/.16S-based approach - Answer-✅The type of method for studying microbiota in which
the gut microbiota DNA is extracted, the 16S rRNA is amplified/sequenced, grouped
into OTUs, identified based on phylogeny, and further identified based on sequence
databases (BLAST)
