Chapter 13 content

Question 1

Define human microbiota

Answer 1

all the microbes that reside on or with human tissue or fluids

Question 2

Microbiome

Answer 2

describes the collective genomes of the microbes that reside in an ecological niche

Question 3

What is the ratio of microbiome

Answer 3

Microbe: human cell

Question 4

When are humans fully sterile

Answer 4

when unborn

Question 5

Upon birth we acquire ________

Answer 5

microbiota

Question 6

What percent of non human genetic material consists of endogenous retroviruses

Answer 6

8 to 10%

Question 7

Does the microbiota fluctuate with general health

Answer 7

yes

Question 8

The precise content of microbiota is _____________, begins at birth, and varies with age, sex, and over the lifespan of the individual

Answer 8

unique to that human

Question 9

What are axenic conditions

Answer 9

state of a culture in which only a single species, variety, or strain of organism is present and entirely free of all other contaminating organism

Question 10

What is the significance that vitamin deficiency is in some animals

Answer 10

microbes can be a significant nutritional source of vitamins

Question 11

What is the significance of underdevelopment of immune system in most animals

Answer 11

microbes are needed to stimulate development of certain host defenses

Question 12

What is the significance of absence of dental caries and periodontal disease in dogs, rats, hamsters

Answer 12

microbes are key players in caries’ formation and gum disease

Question 13

What are the three main things the microbiota do for us

Answer 13

provide essential nutrients
lead to development of healthy immune system
microbiota can protect against pathogens

Question 14

What is the cause of infection and disease in terms of microbes

Answer 14

when there is a lack of balance between equilibrium with microbes

Question 15

Define infection

Answer 15

microbes penetrates host defenses, invades sterile tissue organ and multiplies to cause disease

Question 16

Define disease

Answer 16

defined as any deviation from health

Question 17

Define infectious disease

Answer 17

infection causing damage/disruption to tissues or organ by microbes or their products

Question 18

Define pathogens

Answer 18

organism capable of causing disease in healthy persons with normal immune defenses

Question 19

Define opportunistic pathogens

Answer 19

not pathogenic to a normal healthy person, also organism causing disease when the host’s defenses are compromised or they grow in a part of the body not natural to them

Question 20

how are infectious disease different from normal disease

Answer 20

communicable from person to person and will cause same disease

Question 21

Define pathogenicity

Answer 21

ability of a microbes to establish itself in the host and cause damage/disease

Question 22

Define virulence

Answer 22

the degree to which an organism is pathogenic, it determines a microbes abiltiy to establish itself and cause damage

Question 23

Define virulence factor

Answer 23

genetically encoded structures, characteristics or products of the microbe that contribute to the infection or disease state

Question 24

What are invasin

Answer 24

establishment of an alien microbial type in a resident community

Question 25

what are virulence factors

Answer 25

invasin vi antigen endotoxin exo enzyme

Question 26

Define endotoxin

Answer 26

toxin present in a bacterial cell and is released when the cell disintegrates

Question 27

What is an exoenzyme

Answer 27

excreted enzyme

Question 28

What is the most lethal toxin known

Answer 28

C botulinum exotoxin

Question 29

describe what C botulinum looks like

Answer 29

large protein with many subunits

Question 30

Where does C botulinum bind to

Answer 30

binds selectively and irreversibly to nerve cell receptors, interfering with neural transmission by blocking the release of Ach, causing muscle paralysis

Question 31

Define toxins

Answer 31

specific chemical products of microbes that promote infection and disease by directly damaging host tissues and disabling the immune system

Question 32

What are exotoxins

Answer 32

proteins with a strong specificity for a target cell and extremely powerful, deadly effects, by damaging the cell membrane and initiating lysis or disrupting intracellular function

Question 33

What are exotoxins produced by

Answer 33

bacteria and fungi

Question 34

What are hemolysins

Answer 34

exotoxins that cause lysis of red blood cells

Question 35

What does the exotoxin C. botulinum do

Answer 35

interfere with transmission of nerve muscle stimuli

Question 36

What does C. tetani exotoxins do

Answer 36

block the action of certain spinal neurons

Question 37

Do viruses produce toxins

Answer 37

no

Question 38

Define symptom

Answer 38

subjective evidence of disease as sensed by the patient

Question 39

Define assymptomatic

Answer 39

infections that do not produce overt indication

Question 40

define syndrome

Answer 40

when a disease can be identified or described by a defined collection of signs and symptoms

Question 41

What are signs

Answer 41

evidence of disease by an observer

Question 42

Define incubation period

Answer 42

time from initial contact with the infectious agent to the appearance of first symptoms; agent is multiplying but damage is insufficient to cause symptoms

Question 43

Define prodromal stage

Answer 43

vague feelings of discomfort; nonspecific complaints

Question 44

Define period of invasion

Answer 44

mulitplies at high levels, becomes well established, more specific signs and symptoms

Question 45

Define convalescent period

Answer 45

as person begins to respond to the infection, symptoms decline; in an event that the patient does not recover and dies the infection is terminal

Question 46

What does it mean when disease is communicable

Answer 46

capable of spreading person to person

Question 47

Define contagious

Answer 47

how easy an infectious disease spreads from person to person

Question 48

What does the severity of contagion depend on

Answer 48

pathogen and mode of transmission

Question 49

T/F infectious disease can be contagious during any stage of disease

Answer 49

T

Question 50

which periods of disease are more likely to be associated with transmissibility

Answer 50

depends on the pathogen

Question 51

Define nosocomial infection

Answer 51

infections acquired during a hospital/clinical visit that was not there originally

Question 52

What does duration of infection depend on

Answer 52

pathogen immune response medical treatment received

Question 53

Define acute infeciton

Answer 53

rapid onset with severe but short lived effects

Question 54

Define chronic infection

Answer 54

infections that progress and persist over long periods of time

Question 55

Define latent infection

Answer 55

casual pathogen goes dormant for extended periods of time with no active replication and therefore no host symptoms and signs

Question 56

Which portal is most used by pathogens

Answer 56

respiratory

Question 57

Define infectious dose

Answer 57

minimum number of microbes to cause disease

Question 58

Bacterial, fungal, and protozoal pathogens attach most often by appendages and surface structure such as

Answer 58

fimbriae, pili, or adhesive slimes

Question 59

Define adhesion

Answer 59

microbes gain a stable foothold at the portal of entry; depend on binding between specific molecules on host and pathogen

Question 60

What do virulensce factos directly contribute to with phase 3

Answer 60

tissue damage

Question 61

What is the initial response of phase 3

Answer 61

white blood cells called phagocytes

Question 62

Following invasion, successful multiplication of the pathogen leads to

Answer 62

infection

Question 63

What is systemic infection

Answer 63

throughout the body

Question 64

What is focal infection

Answer 64

breaks loose and disseminates

Question 65

What is polymicrobial or mixed infection

Answer 65

more than one species

Question 66

Define primary infection

Answer 66

can practically be viewed as the root cause of an individuals current problem

Question 67

Define secondary infection

Answer 67

complication of the primary infection

Question 68

Define latency

Answer 68

after the initial symptoms in certain chronic diseases, the microbe can periodically become active and produce a recurrent disease that may or may not shed during the latent stage

Question 69

Define carrier

Answer 69

individual who inconspicuously shelters a pathogen and spreads it to others

Question 70

incubation carriers

Answer 70

spread during incubation period

Question 71

convalescent carriers

Answer 71

reoperating without symptoms

Question 72

chronic carrier

Answer 72

individual who shelters the infectious agent for a long period

Question 73

Define epidemiology

Answer 73

study of the frequency and distribution of disease and other health related factors in defined human populations