Microbiome 8.2

Question 1

The Intestinal microbiota offer protection against enteric pathogen infections through?
(3 THINGS)

Answer 1

(I) Saturation of colonization sites and consumption of nutrients limit pathogen access to host tissues;
(II) the microbiota prime innate immunity by stimulating MUCIN PRODUCTION, immunoglobulin (Ig)A, and antimicrobial peptides (AMPs)
(III) microbiota stimulate INTERLEUKIN (IL)-22 expression, which increases epithelial AMPs, and IL-1β production, which promotes recruitment of inflammatory cells

Question 2

We tend to emphasize _____ microorganisms (pathogens) but more microorganisms are beneficial than harmful

Answer 2

harmful

Question 3

2 catagories of beneficial microorganisms

Answer 3

Commensals

Mutuals

Question 4

define Commensals microorganisms

Answer 4

where two organisms live together and one benefits and the other does not

Question 5

define mutual microorganisms

Answer 5

where two organisms live together and both benefit by this interaction
*most microbiomes, may be only place a microbe survives

Question 6

Microbiota (microbiomes) are independent or interacting populations

Answer 6

interacting populations

Question 7

The environment in which a microbiome lives is its

Answer 7

habitat (The oral cavity is a microbial habitat)

Question 8

The collection of organisms in the oral cavity is called the?

Answer 8

oral Microbiota

Question 9

Ecosystem refers to all of the?

Answer 9

living organisms PLUS physical and chemical constituents in an environment (The oral cavity is an ecosystem)

Question 10

Microbial Ecology is the study of?

Answer 10

microbes in their natural environments

Question 11

Diversity and abundances of microbes are controlled by?

Answer 11

resources (nutrients) and environmental conditions (e.g., salinity, temp, pH, O2)

Question 12

The activities of microbial communities can affect the _______ and _____ properties of their habitats

Answer 12

chemical and physical

Question 13

define Cooperation

Answer 13

each species of microbe contributes something to the microbial community for the good of all members of the community

Question 14

define competition

Answer 14

each species of microbe is in competition with other species of a microbial community and will do anything it needs to maintain its niche (this usually dictates the number of member of each species in an environment)

Question 15

warfare definition

Answer 15

bacteriocins (e.g., colicins produced by Escherichia coli), other antibacterial proteins, and metabolites that deter other species from growing

Question 16

the best studied of the human microbiomes is?

Answer 16

the gut

Question 17

Microorganisms in the colon can live as?

Answer 17

commensals, mutuals, OR pathogens

Question 18

Many Microorganisms in the colon assist in what 3 common things?

Answer 18

1) digestion
2) synthesis of vitamins, nutrients, metabolites
3) out-compete certain pathogens

Question 19

how do Microorganisms in the colon assist in digestion?

Answer 19

Bacteria in the human gut are responsible for metabolizing complex carbohydrates (including cellulose) to provide small-chain fatty acids such as acetate, propionate,
and butyrate that can be readily transported and used by the cells of our body

Question 20

The gut microbiome has been shown to be critically involved? (6)

Answer 20

• in our behavior
• in development of our immune system
• development or prevention of obesity
• in development of inflammatory disease
• development or prevention of cancer
• in the success or failure of cancer immunotherapy

Question 21

Does our body or our alimentary tract have more cells?

Answer 21

The alimentary tract- has more bacterial cells than our own cells in our entire body by a factor of 10!

Question 22

Of the approximately 200 unique species of bacteria that colonize the gut, most are members of?

Answer 22

1. Actinobacteria (e.g., Bifidobacterium)
2. Bacteroidetes (e.g., Bacteroides)
3. Firmicutes (e.g., Eubacterium, Ruminococcus, Faecalibacterium, Blautia)

Question 23

Can gut bacteriophages in the gut be seen in circulation?

Answer 23

Yes. bacteriophages are absorbed and can also be found in blood circulation

Question 24

A significant part of this microbiome are the ______ that regulate the bacterial microbiome

Answer 24

bacteriophages

Question 25

define mucins

Answer 25

a glycoprotein constituent of mucus

Question 26

Some of the bacteria in the gut graze on the carbohydrates, the ____ that line the epithelium

Answer 26

mucins

Question 27

In regards to oxygen, the large intestine is?

Answer 27

anaerobic

Question 28

what part of human biome has the highest bacterial content?

Answer 28

Large intestine; 1010 to 1011 per gram

Question 29

T or F. •Microbiota of intestine is stable

Answer 29

TRUE. remarkably stable like a fingerprint or genetic signature

Question 30

T or F. Many bacterial species are loosely attached to gut

Answer 30

FALSE. they are FIRMLY attached, otherwise they’d be washed away with food

Question 31

What does Pili enable the microbes to do?

Answer 31

1) colonize the epithelium of specific host organs
2) help microbes stay in the intestinal tract by binding to human mucus or mannose sugars present on intestinal surface structures

Question 32

T or F. Antibiotics have a profound effect on the composition of the microbiota

Answer 32

TRUE.

Question 33

During and after a 5-day course of oral ciprofloxacin there is a decreased diversity in ____ microbiota?

Answer 33

gut

**roughly one third of the bacterial taxa changed during ciprofloxacin administration

Question 34

A study of the human fecal microbiota demonstrated that a 7-day course of clindamycin reduced diversity within the _____ genus and led to increased frequencies of highly antibiotic-resistant clones

Answer 34

Bacteroides genus

Question 35

what causes meningitis?

Answer 35

Nesseria meningitidis