32 - Microbiota (Normal Flora)

Question 1

what is the basis of all host-pathogen relationships?

Answer 1

the exploitation by one organism (pathogen/parasite) of the environment provided by another (the host)

Question 2

____________ replicate within the host and multiply to produce a very large number of progeny, causing an overwhelming infection

Answer 2

MICROparasites

Question 3

____________ progeny usually leave the host to continue the cycle. the level of infection is determined by the numbers of the organisms that enter the body

Answer 3

MACROparasites

Question 4

What are Koch’s Postulates

Answer 4

The microbe must be present in every case of the disease

the microbe must be isolated from the diseased host and grown in pure culture

the disease must be reproduced when a pure culture is introduced into a non-diseased susceptible host

the microbe must be recoverable from an experimentally infected host

Question 5

what body areas should be sterile?

Answer 5

Blood
body fluids (CSF, pleural fluid, synovium, pericardial fluid, peritoneal fluid, urine)
tissues (e.g. bone)

Question 6

typical adult contains ______ “self” cells and about ______ times that many microorganisms

Answer 6

10^13, 10

Question 7

T/F in health, there is normal microbiota deep in tissues

Answer 7

False

Question 8

when is the normal microbiota established?

Answer 8

Shortly after birth

Question 9

Is the normal microbiota essential for life?

Answer 9

no

Question 10

what kind of organisms benefit from the host without causing harm

Answer 10

commensals

Question 11

__________ is the presence, growth, and multiplication of bacteria at a specific body site with NO noticeable symptoms

Answer 11

colonization

Question 12

___________ is the presence and movement of bacteria into a body area (e.g., tissue) with growth and multiplication and NOTICEABLE symptoms (e.g. fever, pus, inflammation

Answer 12

infection

Question 13

What vitamins can be produced by normal flora organisms

Answer 13

Vit. K & B

Question 14

how will the normal flora influence the GI tract

Answer 14

stimulate it

Question 15

what does the normal flora do for the immune system?

Answer 15

general stimulation

Question 16

T/F Normal flora will produce inhibitory substances to prevent pathogens

Answer 16

True, pathogens are competition for nutrients

Question 17

what can disturb the intestinal microbiota

Answer 17

any cause of diarrhea
emotional stress
sudden changes in diet
illness- changes in eating and activity
antibiotic therapy

Question 18

which medication(s) may affect the pt’s microbiota

Answer 18

all of them

Question 19

what common organisms are present on the skin

Answer 19

staph epidermidis
corynebacterium sp
propionibacterium acnes

Question 20

where will the microbes be trapped in the respiratory tract

Answer 20

the mucus traps microbes, ciliated epithelium sweeps organisms out

Question 21

the __________ tract is the primary carriage site of staph aureus

Answer 21

respiratory

Question 22

what potential pathogens will have transient carriage sites within the respiratory tract

Answer 22

streptococcus pneumoniae
neisseria meningitidis
haemophilus influenzae
ear and sinus infections, pneumonias, meningitis

Question 23

where is the widest variety of the microenvironments present with humans

Answer 23

the mouth

Question 24

where is the only site where normal flora routinely causes disease in immunocompentent hosts?

Answer 24

the mouth

Question 25

what will anaerobes cause in the mouth

Answer 25

perio disease

Question 26

at what age will streptococci be established in the mouth

Answer 26

4-12 hours after birth

Question 27

T/F Normal flora in the mouth will break down macromolecules

Answer 27

False, macromolecules don't stick around long enough, low molecular weight carbohydrates are the ones quickly broken down by normal flora

Question 28

what will determine what microbiota is present in the mouth

Answer 28

mechanical forces chemical action of saliva types of foods consumed physical consistency of food consumed

Question 29

what will determine the number of microbiota when looking at the GI tract

Answer 29

the conditions of the organ (e.g. stomach <10 organisms/ml with low pH whereas upper intestines < 10^3/ml)

Question 30

which organ has the largest population of microbiota in all of the body?

Answer 30

colon (10^10 bacteria per gram of feces)

Question 31

T/F Colon is primarily anaerobes

Answer 31

true

Question 32

What are the vaginal microbiota influenced by?

Answer 32

pH (will change at puberty and menopause)

Question 33

what organism helps keep other organisms out of the vagina during child-bearing years

Answer 33

lactobacilli