Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Microbiology Exam 2 (Modules 3-5) > Chapter 11 > Flashcards

Chapter 11 Flashcards

You may prefer our related Brainscape-certified flashcards:
Biology 101 flashcards
1
Q

the sum total of all microbes found on and in a normal human that is critically important to the health and functioning of its host organism

A

human microbiome

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

rapidly lost microbes in the human microbiome

A

transients

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

any deviation from health, as when the effects of microbial infection damage or disrupt tissues and organs

A

disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

about how many protein-encoding genes do human cells contain?
-found from research in the Human Microbiome Project (HMP)

A

21,000

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are some more recently and newly discovered regions of the human body that harbor normal microbiota?

A

lungs (lower resp tract)
bladder and urine
breast and breast milk
amniotic fluid and fetus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are some recently discovered sites in which DNA from microbiota has been detected?

A

brain

blood stream

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

relationship in which microorganisms compete for survival in a common environment by taking actions that inhibit or destroy another organism

ie. between normal microbiota and intruders

A

microbial antagonism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

True or False

The uterus and its contents are sterile during embryonic and fetal development

A

False, and the placenta itself also harbors a small but significant array of bacteria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

where do babies get a microbiome?

A

the womb, the vaginal canal or during c section, breast milk, caregivers, environment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

the vaginas of healthy women of child bearing age contain a variety of bacteria, but are especially rich in __________ bacteria, which are capable of digesting milk.

A

Lactobacillus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

sites previously known to harbor normal bacteria

A 
skin and adjacent mucous membranes
upper resp tract
gastro tract including mouth
outer portion of urethra
external genitalia
vagina
eternal ear canal
external eye (lids, conjunctiva)

*now know in lungs, bladder, breast/breastmilk, amniotic fluids/fetus, lungs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

a microbe whose relationship with its host is parasitic and results in infection and disease

A

pathogen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

true (primary) pathogens

A

capable of causing disease in healthy persons with a normal immune defenses; generally associated with a specific, recognizable disease, which may vary in severity from mold (colds) to severe (malaria) to fatal (rabies).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Opportunistic pathogens

A

cause disease when the host’s defenses are compromised or when the pathogens become established in a part of the body that is not natural to them.

; Pseudomonas species and Candida albicans

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

in infection, the relative capacity of a pathogen to invade and harm host cells

A

virulence

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

the term virulence and _________ are often used interchangeably

A

pathogenicity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

__________ is the accurate term for describing the degree of pathogenicity

A

virulence

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what two factors is virulence determined by

A

its ability to

  1. establish itself in the host
  2. cause damage
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

to cause damage, microbes produce ______ or induce a host response that is actually injurious to the host

A

toxins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

what must microbes do to establish themselves in a host

A

enter the host
attach firmly to host tissues
negotiate the microbiome
survive host defenses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

any characteristic or structure of the microbe that contributes to the preceding activities is called a __________

A

virulence factor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

a set of rules for determining the cause of an unknown infectious condition

A

Koch’s Postulates

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

involving multiple distinct microorganisms

A

polymicrobial

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

what is the most common portal of entry?

A

respiratory tract

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

route of entry for an infectious agent; typically a cutaneous or membranous route

A

portal of entry

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

organisms coming from outside the body

A

exogenous

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Portal of Entry: Skin

examples of organism/disease and how access is gained

A

organisms: Staphylococcus aureus, Streptococcus pyogenes, Clostridium tetani, Herpes simplex (type 1), Helminth worms, viruses, rickettsias, protozoa (.e malaria, West Nile virus), Haemophilus aegyptius, Chlamydia trachomatis, Neisseria gonorrhoeae
access: nicks, abrasions, areas of broken skin, mucous membranes of the lips, burrow through the skin, insect bites, conjunctiva of the eye

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Portal of Entry: GI tract

A

organisms: Salmonella, Shigella, Vibrio, E. coli, poliovirus, Hep A., echovirus, rotavirus, enteric protozoans (Giardia lamblia, Entamoeba histolytica
access: drinking contaminated foods/fluids, fomites (inanimate objects contaminated with the infectious organism)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Portal of Entry: Resp tract

A

organisms: bacteria causing meningitis, influenza, measles, mumps, rubella, chicken pox, common cold, Streptococcus pneumoniae, Klebsiella, Mycoplasma, Cryptococcus, Pneumocystis, Mycobacterium tuberculosis, Histoplasma
access: via inhaling of offending organism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Portal of Entry: Urogenital Tract

A

organism: HIV, Trichomonas, Hep B., syphilis, Treponema pallidum, Neisseria gonorrhea, Chlamydia trachomatis, herpes, genital warts
access: skin/mucosa of penis, external genitalia, vagina/cervix, urethra; may enter through an unbroken surface of through a cut or abrasion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Infectious dose

A

the minimum number of microbes required to cause an infection

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Infectious dose for typhoid fever

A

10,000 bacteria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Infectious dose for Cholera

A

1,000,000,000 bacteria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

infectious dose for Coxiella burnetii (Q fever)

A

a single cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

process by which microbes gain a more stable foothold on host tissues at the portal of entry; dependent on binding between specific molecules on both the host and pathogen (limits the types of cells pathogens can bind to)

A

Adhesion (step two)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Adhesion:

attach most often by mechanisms such as fimbriae (pili), surface proteins, and adhesive slimes or capsules

A

Bacterial, fungal, and protozoal pathogens

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

adhesion:

attach by means of specialized receptors

A

viruses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

adhesion:

mechanically fastened to the portal of entry by suckers, barbs, and hooks.

A

Parasitic worms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Microbial Infections: Step 3

A

surviving host infections
;microbes that are not established in a normal biota are likely to encounter resistance from host defenses ESPECIALLY from phagocytes (a WBC)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

used by some pathogens to avoid phagocytes during step 3 of infection

A

Antiphagocytic factors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

species of both Streptococcus and Staphylococcus produce __________, substances that are toxic to white blood cells.

A

leukocidins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

some micros secrete an extracellular surface layer (slime or capsule) which does what?

A

this makes it difficult for phagocytes to engulf them

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

what is step four of infection?

A

Causing Disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

structures or capabilities that allow a pathogen to cause infection in a host

A

virulence factors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

what are the three major ways that microorganisms damage their host?

A
  1. directly through the action of enzymes or toxins (both endo and exotoxins)
  2. indirectly by inducing the host’s defenses to respond excessively or inappropriately
  3. epigenetic changes made to host cells by microbes
46
Q

an extracellular enzyme chiefly for hydrolysis of nutrient macromolecules that are otherwise impervious to the cell membrane.
; functions in saprobic decomposition of organic debris and can be a factor in invasiveness of pathogens

-> break down and inflict damage on tissues

A

exoenzyme

47
Q

enzyme that digests the protective coating on mucous membranes and is a factor in amoebic dysentery

A

mucinase

48
Q

enzyme which digests hyaluronic acid, the substance that cements animal cells together (important virulence factor in staphylococci, clostridia, streptococci, and pneumococci)

A

hyaluronidase

49
Q

enzyme produced by pathogenic staphylococci, causing clotting of blood or plasma

A

Coagulase

50
Q

dissolves fibrin clots and assists in the invasion of damaged tissues

A

bacterial kinases

51
Q

specific chemical product of microbes that is poisonous to other organisms

A

toxin

52
Q

lyse red blood cells

A

hemotoxins

53
Q

when red blood cells burst and release hemoglobin pigment

A

hemolyze

54
Q

proteins with strong specificity for a target cell and extremely powerful, sometimes deadly, effects
; is a bacterial toxin, and generally affect cells by damaging cell membranes and causing lysis or by disrupting intracellular function

A

exotoxins

55
Q 
class of bacterial exotoxin that disrupts the cell membrane of red blood cells
; causes red blood cells to hemolyze (burst and release hemoglobin pigment)
A

hemolysins

56
Q

what hemolysins (bacterial exotoxin) increase pathogenicity?

A

streptolysins (or Streptococcus pyogenes) and the alpha and beta toxins of Staphylococcus aureus.

57
Q

a chemical called lipopolysaccharide (LPS) which is a part of the outer membrane of gram negative cell walls

;gram negative bacteria shed LPS molecules into tissues or into the circulation

A

endotoxins

58
Q

lipopolysaccharide is an endotoxin present in what bacterial outer cell membrane?

A

gram negative bacteria

59
Q

how does endotoxin differ from exotoxins?

A

endotoxin has a variety of systemic effects on tissues and organs, and can cause things like fever, inflammation, hemorrhage, and diarrhea.

*Blood infections by gram-negative bacteria such as Salmonella, Shigella, Neisseria meningitidis, and E. coli and particularly dangerous and can lead to fatal endotoxic shock.

60
Q

exotoxins are given off by ________, endotoxins are given off by gram-neg ___ ____.

A
  1. cells

2. cell walls

61
Q

exotoxins have highly ______ targets, endotoxins have more ________ effects.

A
  1. specific

2. generalized

62
Q

it is probably the case that more microbial diseases are the result of _____ damage, or the host’s excessive or inappropriate response to a microorganism.

A

indirect

63
Q

pathogenicity is not always a trait inherent in microorganisms, but is really a consequence of what?

A

of the interplay between microbe and host

64
Q

Epigenetic changes in host cells

A

microbes have been shown to shut down or activate regions of DNA in the host cell, via epigenetic processes

65
Q

what are some examples of epigenetic processes?

A

binding to host cell histones, binding to small RNAs used for the silencing of genes, binding to chromatin itself, etc.

-> these can harm the host cell or change its function in some way that favors persistence of the microbes in or on it.

66
Q

when there is a decrease in a host’s ability to mount an immune defense

A

immunocompromised

67
Q

opportunistic pathogens

A

microbes that take advantage of immunocompromised hosts

68
Q

infection that is in a location different than the initial infection (goes from local to other tissues)
ie. periodontal infections leading to cardiovascular consequences

A

focal infection

69
Q

infections that are only in one location

ie. boils, warts, fungal skin infections

A

localized infection

70
Q

infection that spreads to several sites and tissue fluids via bloodstream, nerves, cerebrospinal fluid
ie. mumps, rubella, AIDS, anthrax, chickenpox, typhoid, syphilis

A

systemic infection

71
Q

several agents establish themselves simultaneously at the infection site
ie. human bite infections, wound infections, gas gangrene

A

mixed/polymicrobial infection

72
Q

the initial infection

ie. can be any infection

A

primary infection

73
Q

a second infection caused by a different microbe, which complicates a primary infection; often a result of lowered host immune defenses
ie. influenza complicated by pneumonia or common cold complicated by bacterial otitis media

A

secondary infection

74
Q

infection comes on rapidly, with severe but short-lived effects
ie. influenza

A

acute infection

75
Q

infection that progresses and persists over a long period of time
ie. HIV

A

chronic infection

76
Q

any objective evidence of disease as noted by an observer

A

sign

77
Q

subjective evidence of a disease as sensed by a patient

A

symptom

78
Q

in general, ____ are more precise than _______, though both can have the same underlying cause.

Options: signs, symptoms

A
  1. Signs

2. Symptoms

79
Q

when a disease can be identified or defined by a certain complex of signs and symptoms, it is termed what?

A

syndrome

80
Q

the earliest symptoms of disease usually come from the activation of the body defense called __________.

A

inflammation

81
Q

what are some signs and symptoms of inflammation?

A

signs:
- edema
- granulomas (solid mass or nodule of inflammatory tissue containing modified macrophages and lymphocytes) and abscesses (inflamed, fibrous lesion enclosing a core of pus)
- walled off collections of inflammatory cells and microbes in the tissues
- lymphadenitis (swollen lymph nodes)

symptoms:

  • fever
  • pain
  • soreness
  • swelling
82
Q

changes in the number of circulating ___________, as determined by special counts, are considered to be signs of possible infection.

A

white blood cells

83
Q

term for an increase in the level of white blood cells

A

leukocytosis

84
Q

term for decrease in the number of white blood cells

A

leukopenia

85
Q

clinical term for blood infection, which refers to a general state in which microorganisms are multiplying in the blood and are present in large number.

A

septicemia

86
Q

refers to when small numbers of bacteria are found in the blood, but not necessarily multiplying

A

Bacteremia

87
Q

refers to when small numbers of viruses are found in the blood, but not necessarily multiplying

A

viremia

88
Q

what is step five of infection?

A

Vacating the Host- Portals of Exit

89
Q

What are the five steps of infection?

A
  1. Becoming Established-Portals of Entry
  2. Becoming Established-Attaching to the Host and Interacting with the Microbiome
  3. Becoming Established-Surviving Host Defenses
  4. Causing Disease
  5. Vacating the Host-Portal of Exit
90
Q

route through which a pathogen departs from the host organism

A

portal of exit

91
Q

what are the ways in which a pathogen is shed or released from the body?

A

excretion, secretion, discharge, or sloughed

92
Q

in many cases the portal of exit is the _____ as the portal of entry, but some pathogens use a different route.

A

same

93
Q

the state of being inactive; the infectious agent retreats into a dormant state called _____.
ex: a _______ virus or _______ infection

A

Latency

Latent

94
Q

what can a microbe do throughout a latent state?

A

the microbe can periodically become active and produce a recurrent disease

ie. The viral agents of Hep B., Herpes zoster, AIDS, herpes simplex, and Epstein-Barr can persist in the host for long periods

95
Q

term for a morbid complication that follows a disease; such as permanent damage to tissues or organs

ie. Strep throat can lead to rheumatic heart disease

A

sequela

96
Q

the period from the initial contact with an infectious agent to the appearance of the first symptoms

; during this period the agent is multiplying at the portal of entry but has not yet caused enough damage to elicit sx

A

incubation period

97
Q

the majority of infections have incubation periods ranging between

A

2 and 30 days

98
Q

a short period of mild sx occurring at the end of the period of incubation -> indicates the onset of a disease; about 1-2 days

ie. headache, muscle aches, fatigue, upset stomach, general malaise

A

prodromal stage

99
Q

third phase of infection where the infectious agent multiplies at high levels, exhibits the greatest virulence, and becomes well established in its target tissue

; often marked by fever and other prominent and more specific signs and symptoms like cough, rashes, diarrhea, severe pain, jaundice, loss of muscle control, but depends on the infection

-> extremely variable length of this period

A

Acute Phase

100
Q

fourth phase of infection where the patient begins to respond to the infection and symptoms decline (sometimes dramatically or slowly); the patient’s health begins to gradually return

A

Convalescence (recovery)

101
Q

fifth phase of infection that only some infections have, in which the organism lingers for months, years, or indefinitely after the patient is completely well or the organism is gone by sx continue

ie. typhoid fever or chronic Lyme Disease

A

Continuation phase

102
Q

many microbes are released primarily in the _____ phase, but others can be transmitted during all of these phases

A

acute

103
Q

A patient has been diagnosed with E. coli septicemia. Which of the following characteristics are associated with endotoxins? Select all that apply.
a. toxicity in minimal concentration

b. gram-negative bacteria
c. presence of fever
d. protein composition
e. released by cells during lysis

A

b, c, e

104
Q

11.2 Outcome:

differentiate between a microbe’s pathogenicity and its virulence

A

pathogenicity is the ability of a pathogen to cause disease

virulence is the ability of a pathogen or microbe to infect or damage a host

105
Q

11.2 Outcome

List the steps a microbe has to take to get to the point where it can cause disease

A
  1. Becoming Established - Portal of Entry
  2. Attaching to Host (adhesion) and Interacting with Microbiome
  3. Surviving Host Defenses
  4. Causing Disease
  5. Vacating Host - Portal of Exit
106
Q

Microbial hyaluronidase, coagulase, and streptokinase are examples of __________

A

exoenzymes

107
Q

11.2 Outcome

List several portals or entry and exit

A

entry: mucous membranes, nicks on the skin, gastrointestinal tract, respiratory tract, urogenital tract,
exit: blood, feces, urine, saliva, skin cells, respiratory tract

108
Q

11.2 Outcome

Explain the significance of polymicrobial infections

A

they are infections consisting of multiple microbes, which changes the need for antibiotics, and presents the risk of using an antibiotic that does not adequately eliminate all microbes causing infection (resistance)

109
Q

11.2 Outcome

Define infectious dose and explain its role in establishing infection

A

it is the minimum number of microbes requires for an inoculating dose to cause an infection

110
Q

11.2 Outcome

Describe three ways microbes cause tissue damage

A
  1. directly through the action of enzymes
  2. directly through the action of toxins (endo or exo)
  3. indirectly through inducing the host’s immune system to respond excessively or inappropriately
  4. EPIGENETIC CHANGES
111
Q

11.2 Outcome

compare and contrast major characteristics of endotoxins and exotoxins

A

exotoxins:

  • produced by live bacteria that are gram pos and neg
  • specific target
  • protein composition
  • often has enzymatic activity

endotoxins:
- predominantly a part of the cell wall of gram neg bacteria
- systemic effects
- lipopolysaccharide composition

112
Q

11.2 outcome

provide a definition of virulence factors

A

structures or capabilities that allow a pathogen to cause infection in a host

Microbiology Exam 2 (Modules 3-5) (13 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions