Microbiology Flashcards

Question

colonization

Answer 1

establishment of population of organisms which live/multiply (e.g. normal flora)

Answer 2

occurs when colonized organisms cause a host response (e.g. inflammation)

Answer 3

occurs when infection causes host tissue damage (i.e. disease)

Answer 4

microorganisms that normally reside at a given site and under normal circumstances do not cause disease

Answer 5

an "ecological community" of commensal, symbiotic, and pathogenic microorganisms

Answer 6

the collective genomes of the microorganisms that reside in an environmental niche or the microorganisms themselves

Answer 7

relation between individuals of two species in which one species obtains food or other benefits from the other without either harming

Answer 8

disease-causing capacity

Answer 9

protects from pathogens modulates immune system assists with nutrition & metabolism opportunistic pathogens (in immunocompromised patients or after surgical procedures allow entry into other tissues leading to infections)

Answer 10

by synthesizing vitamin K, thiamine (B1), folic acid (B9), and B12 by helping to break down starches, sugars, and proteins by aiding in recycling bile salts and certain hormones

Answer 11

by occupying attachment sites by competing for resources by modulating the environment (e.g. producing acid/antibiotics)

Answer 12

the human microbiota has approx. 10^14 bacterial cells, which is 10 times more than the number of human cells in our whole body

Answer 13

fiber and things to feed your flora (e.g. eating good foods rather than buy expensive supplements)

Answer 14

OTC products that are variable (with some of the names of the organisms are even fictitious) and for which hard evidence of benefit is lacking (some studies even showed harmful effects)

Answer 15

``` low pH (5.0 - 6.0) lower temperature (about 5◦ C lower) than rest of body high osmotic pressure in salty sweat ``` dry (moist skin areas can support a different bacterial population than dry areas) antimicrobial substances present (e.g. sebum, lysozyme, substances produced by other microorganisms) and competition with other bacteria

Answer 16

MOST IMPORTANT: Staphylococcus epidermidis (Gram+ cocci in clusters) ``` OTHERS: Staphylococcus aureus (Gram+ cocci in clusters; potential pathogen) ``` Corynebacterium species (a.k.a. diptheroids, Gram+ rods) Propionibacterium acnes (Gram+ rods) various Streptococci (Gram+ cocci in chains), some yeasts

Answer 17

Gram+ cocci in clusters, found on skin

Answer 18

Gram+ cocci in clusters; potential pathogen found on skin

Answer 19

a.k.a. diptheroids; Gram+ rods found on skin

Answer 20

Gram+ rods found on skin

Answer 21

aerobic or facultative anaerobic (can be anaerobic) MOST IMPORTANT: Streptococcus viridans (e.g. Streptococcus sanguinis and Streptococcus mutans) which are Gram+ cocci in chains OTHERS: Eikenella corrodens (Gram negative rods), nonpathogenic Neisseria species (Gram negative cocci), Haemophilus species (Gram negative rods) some potential pathogens (e.g. Staphylococcus aureus, Neisseria meningitidis, Haemophilus influenzae)

Answer 22

Gram+ cocci in chains found in the mouth E.g. Streptococcus sanguinis and Streptococcus mutans called viridans (green) because when grown on a blood agar plate they cause partial hemolysis (called alpha hemolysis) that produces a green discoloration

Answer 23

when grown on a blood agar plate, these bacteria cause partial hemolysis (alpha hemolysis) that produces a green discoloration

Answer 24

Gram- rods found in the mouth

Answer 25

Gram- cocci found in the mouth (can be pathogenic, e.g. Neisseria meningitidis)

Answer 26

Gram- rods found in the mouth (can be pathogenic, e.g. Haemophilus influenzae)

Answer 27

stomach flora are acid resistant (e.g. Lactobacillus species) small intestine flora are largely anaerobic and prefer a more alkaline environment (e.g. Peptostreptococcus species) ``` large intestine flora are largely anaerobic; MOST IMPORTANT: Bacteriodes fragilis (Gram- rod, strict anaerobe) Escherichia coli (Gram- rod, facultative anaerobe) ``` OTHERS: Enterococcus species (and many more) Some potential pathogens (e.g. Helicobacter, Campylobacter, Clostridium species)

Answer 28

an acid-resistant stomach flora that are Gram+ rods also maintain the low pH of the vagina

Answer 29

a small intestine flora

Answer 30

Gram- rod, strict anaerobe found in the colon

Answer 31

Gram- rod, facultative anaerobe found in the colon

Answer 32

Lactobacillus species (Gram+ rods) maintain the low pH of the vagina Others: Candida albicans (yeast), Group B Streptococci (Gram + cocci in chains)

Answer 33

yeast found in the GU system

Answer 34

Gram+ cocci in chains found in the GU system the normal vaginal flora of as many as 25 % of women of childbearing age includes Group B Streptococcus, and it may cause neonatal sepsis and meningitis if acquired by the baby at birth

Answer 35

the degree of pathogenicity (i.e. capacity to cause disease)

Answer 36

includes: toxins adhesion/colonization/invasion factors ability to inhibit immune responses

Answer 37

consists of relatively fixed types of microorganisms regularly found in a given area at a given age; if disturbed, it promptly reestablishes itself

Answer 38

consists of nonpathogenic or potentially pathogenic microorganisms that inhabit body sites for hours, days, or weeks

Answer 39

symbiotic relationship where one partner benefits, while the other seems unaffected

Answer 40

symbiotic relationship where both parties derive benefit

Answer 41

the prevent colonization by pathogens and possible disease by resident microbiota, possibly through competition for receptors or binding sites on host cells, competition for nutrients, mutual inhibition by metabolic or toxic products, mutual inhibition by antibiotic materials or bacteriocins, or other mechanisms

Answer 42

fungi (yeast)

Answer 43

fungi (mold)