Human microbiome

Question 1

when does a fetus start to develop normal flora (hours, days, weeks)

Answer 1

fetus is sterile but colonization will start during the birth process.
hours- skin/nasopharxn
days- Itenstinal tract
weeks- lower Gi

Question 2

What can influence the flora of a newborn

Answer 2

1. Age
2. stress lvl of mother
3. C section vs vaginal
4. feeding
5. antibiotic use
6. meds

Question 3

What is resident flora, are they harmlesss

Answer 3

relatively fixed types of microorganisms reguarly found in a given area (can reestablish self)

are harmless but can produce disease if introduced into foreign locations in high numbers

Question 4

What is transient flora, are they harmless

Answer 4

inhabitat skin or mucus membrans for hours, days, weeks and are derived from the environment

harmless as long as normal resident flora is not disturbed

Question 5

What are resident bacteria of the skin (and are they aerobic or anerobic)

Answer 5

Staphylococcus epidemis (aerobic)
Staphylococcus aureus (aerobic)
Propionibacterium acnes (anerobic)

Question 6

What parts of the ear are sterile

Answer 6

sterile- Usually middle and inner ear

outer ear and auditory cannal contain the same normal flora of the skin

Question 7

What is bacteria of the nasopharynx

Answer 7

Streptococcus pneumoniae

Question 8

What is a bacteria of the oral cavity and what can it cause after dental surgery

Answer 8

Streptococcus mutans

after dental surgeries, there may be a risk of bloodstream infections that can cause endocarditis

Question 9

What are bacteria of the small intestine and where are they foudn

Answer 9

upper part- none cuz bile kills them

Lactobacillu and enterocci predominant in duodenum and prox ileum

Question 10

Bacteria of the large intestine and why they important

Answer 10

99% of the bac in the body
Bacteroids spp.

Produce vits such as vit K

Question 11

what are some bacteria that when changing location from gi to urinary tract will cause infection

Answer 11

e coli

proteus mirabilis

Question 12

what is a resident bacteria of the vagina

Answer 12

Lactobacullus acidophilus

Question 13

What are opportunistic bacteria of the vagina

Answer 13

Fungal vaginitis (candida albicans)
bacterial vaginosis (gardnerella vaginalis)

Question 14

How does normal flora protect you

Answer 14

• Competes for nutrients/receptors (limiting nut. for otherpathogens)
• produces bacteriocins (inhibit growth of similar or closely related strains ex ecoli prevents shigella spp.)

Question 15

How does normal flora influece immune function

Answer 15

In newborns, normal flora stims immune functio and promotes antibody function and t cell

Question 16

What are 2 vits bacteria provide

Answer 16

Vit k and B

Question 17

What are the 2 situations when normal flora can become pathogenic

Answer 17

1. If moves to a new location

2. When indv is immunocompromised/ if normal flora overgrows