Brainscape's Knowledge GenomeTM

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


See full index

Microbiology > Chapter 11: Interactions between Humans and Microbes > Flashcards

Chapter 11: Interactions between Humans and Microbes Flashcards

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

Infectious Disease

A

the disruption of a tissue or organism caused by microbes or their products

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

Do all contacts lead to colonization and then to infection and then to disease?

A

Not all contacts lead to colonization; Not all colonizations lead to infection and Not all infections lead to disease

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

Normal (Resident) Biota

A

microbes that live peacefully and symbiotically in the human body; include an array of bacteria, fungi, protozoa, viruses, and arthropods

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

Human Microbiome Project

A

will identify genetic sequences to determine which microbes are inside and on humans, even though they can’t be cultured in the laboratory; will determine what the normal biota play in human health and disease; uses metagenomics

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

These general parts of the body are microbe free:

A

Internal organs, tissue, and their fluids

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

Sites that harbor normal biota (8)

A

(1) Skin and its adjacent mucous membranes; (2) Respiratory tract; (3) GI Tract (various parts); (4) Outer opening of the urethra; (5) External genitalia; (6) Vagina; (7) External ear canal; (8) External eye

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

Factors that weaken host defenses and increase susceptibility to infection (4)

A

(1) Old age and extreme youth; (2) Genetic and acquired defects in immunity; (3) surgery and organ transplants; (4) Underlying disease

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

Why are normal biota unlikely to be displaced by other microbes?

A

(1) Limited number of attachment sites; (2) Chemical and physiological environment created by normal biota is hostile to others

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

Vaginally delivered baby has been colonized by these microbes (3)

A

streptococci, staphylococci, and lactobacilli

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

These bacteria colonize the large intestine of bottle-fed infants:

A

coliforms, lactobacilli, enteric streptococci, staphylococci

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

Bifidobacterium

A

Breast-fed infants receive this bacterium because it favors the growth factor in milk; metabolizes sugars into acids to protect the infant from intestinal pathogens

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

Which of the following body sites is not colonized by known normal biota?

A. skin and mucous membranes
B. external genitalia
C. gastrointestinal tract
D. kidneys and bladder
E. respiratory tract
A

D. Kidneys and bladder (internal organ)

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

Pathogenicity

A

an organism’s potential to cause infection or disease

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

A true pathogen is capable of…

A

causing disease in a healthy person with normal immune defenses

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

Opportunistic Pathogen

A

cause disease when the host’s defenses are compromised or when they become established in a part of the body that is not natural to them; Not pathogenic to a normal, healthy person

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

Examples of opportunistic pathogens (2)

A

Pseudomonas species; Candida albicans

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

Virulence

A

determined by its ability to establish itself in a host & cause damage (not the same as pathogenicity)

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

Virulence Factor

A

any characteristic or structure of the microbe contributes to its ability to establish itself in the host and cause damage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Portal of Entry

A

the route that a microbe takes to enter the tissues of the body to initiate an infection

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

Exogenous

A

microbe originating from a source outside the body from the environment or another person or animal

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

Endogenous

A

microbe already existing on or in the body – normal biota or a previously silent infection

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

Infectious agents that can enter through more than one portal of entry (3)

A

(1) Mycobacterium tuberculosis can enter through both the respiratory and gastrointestinal tracts; (2) Streptococcus and (3) Staphylococcus can enter through the skin, urogenital tract, and the respiratory tract

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

Infectious Dose (ID)

A

the minimum number of microbes necessary to cause an infection to proceed; smaller ID = higher virulence

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

ID for Rickettsia

A

single cell

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

ID for tuberculosis, giardiasis, and coccidioidomycosis

A

10 cells

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

ID for gonorrhea

A

1,000 cells

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

ID for typhoid fever

A

10,000 cells

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

ID for cholera

A

1,000,000,000 cells

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

Adhesion

A

process by which microbes gain a more stable foothold on host tissues; firm attachment is imperative for causing infection

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

Adhesion Mechanisms (4)

A

(1) fimbriae (pili), (2) surface proteins, (3) adhesive slimes or capsules, (4) specialized receptors

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

Phagocytes

A

cells that engulf and destroy host pathogens by means of enzymes and antimicrobial chemicals

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

Slime or Capsule

A

makes it difficult for the phagocyte to engulf the pathogen

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

Bacteria with slime or capsule (4)

A

(1) Streptococcus pneumoniae, (2) Salmonella typhi, (3) Neisseria meningitidis, and (4) Cryptococcus neoformans

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

Bacteria that can survive inside the phagocyte (3)

A

(1) Legionella, (2) Mycobacterium, and (3) many rickettsias

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

3 ways microorganisms cause damage to their hosts

A

(1) directly through the action of ENZYMES; (2) directly through the action of TOXINS; (3) indirectly by inducing the HOST’S DEFENSES to respond excessively or inappropriately

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

Exoenzyme

A

enzymes secreted by microbes that break down and inflict damage on tissues & dissolve the host’s defense barriers to promote the spread of disease to other tissues

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

Mucinase

A

exoenzyme that digests the protective coating on mucous membranes

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

Toxin

A

a specific chemical product of microbes, plants, and some animals that is poisonous to other organisms

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

Neurotoxins act on…

A

the nervous system

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

Enterotoxins act on…

A

the intestines

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

Hemotoxins…

A

lyse red blood cells

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

Nephrotoxins…

A

damage the kidneys

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

Exotoxins

A

toxins that affect the cell by damaging the cell membrane and initiating lysis and disrupting intracellular function

44
Q

Hemolysins

A

toxins that disrupt the membrane of red blood cells to release hemoglobin

45
Q

Streptococcus pyogenes produces

A

streptolysins (a hemolysins)

46
Q

Staphylococcus aureus produces

A

alpha and beta toxins (hemolysins)

47
Q

Lipopolysaccharide (exotoxin)

A

part of the outer membrane of gram-negative cell walls; causes fever, inflammation, hemorrhage, and diarrhea

48
Q

Blood infections by these 4 bacteria are particularly dangerous

A

(1) Salmonella, (2) Shigella, (3) Neisseria meningitidis, and (4) Escherichia coli

49
Q

Steps Involved When a Microbe Causes Disease in a Host-summary

A

(1) Find portal of entry; (2) Attaching firmly; (3) Surviving host defenses; (4) causing damage; (5) exiting host

50
Q

Necrosis

A

accumulated damage due to pathogens leading to cell and tissue death

51
Q

Sign

A

objective evidence of disease as noted by an observer

52
Q

Edema

A

the accumulation of fluid in afflicted tissue (sign)

53
Q

Lymphadenitis

A

swollen lymph nodes (sign)

54
Q

Symptom

A

subjective evidence of disease as sensed by the patient

55
Q

Syndrome

A

a disease identified by a certain complex of signs and symptoms

56
Q

Leukocytosis

A

increase in white blood cell levels

57
Q

Leukopenia

A

decrease in white blood cell levels

58
Q

Septicemia

A

a general state in which microorganisms are multiplying in the blood and are present in large numbers

59
Q

Bacteremia/Viremia

A

bacteria or viruses are present in the blood but not multiplying

60
Q

Portal of Exit

A

Usually the same as the portal of entry; shed through secretion, excretion, discharge, or sloughed tissue

61
Q

Latency

A

a dormant state of microbes in certain chronic infectious diseases

62
Q

Viral Latency (5)

A

(1) herpes simplex, (2) herpes zoster, (3) hepatitis B, (4) AIDS, (5) Epstein-Barr

63
Q

Bacterial/Protozoan Latency (4)

A

(1) syphilis, (2) typhoid fever, (3) tuberculosis, (4) malaria.

64
Q

Sequelae

A

long-term or permanent damage to tissues or organs caused by infectious disease

65
Q

Sequelae of meningitis

A

Deafness

66
Q

Sequelae of strep throat

A

rheumatic heart disease

67
Q

Sequelae of lyme disease

A

arthritis

68
Q

Sequelae of polio

A

paralysis

69
Q

Incubation Period

A

the time from initial contact with the infectious agent to the appearance of symptoms & ranges from several hours to several years; majority of infections range from 2 and 30 days

70
Q

Prodromal Stage

A

1 – 2 day period when the earliest notable symptoms of infection appear

71
Q

Period of Invasion

A

infectious agent multiplies at high levels, exhibits greatest toxicity, becomes well established in host tissue; marked by fever and other prominent and specific signs and symptoms

72
Q

Convalescent Period

A

patient begins to respond to the infection and symptoms decline

73
Q

Reservoir

A

primary habitat in the natural world from which a pathogen originates; often a human or animal carrier; also soil, water, and plants

74
Q

Transmitter

A

individual or object from which an infection is acquired

75
Q

Carrier

A

an individual who inconspicuously shelters a pathogen, spreads it to others without any notice, and who may not have experienced disease due to the microbe

76
Q

Majority of animal reservoir agents

A

arthropods such as fleas, mosquitoes, flies, and ticks

77
Q

Biological Vector

A

INFECTED; actively participates in a pathogen’s life cycle, serving as a site in which it can multiply or complete its life cycle; Mosquitoes and malaria

78
Q

Mechanical Vector

A

NOT INFECTED; carries the microbe more or less accidentally on its body parts

79
Q

Zoonosis

A

an infection indigenous to animals but naturally transmissible to humans

80
Q

Nonliving Reservoirs

A

natural habitats important in diagnosis of disease and epidemiological studies

81
Q

Communicable Disease

A

host can transmit the infectious agent to another host; synonymous to infectious

82
Q

Contagious

A

a disease that is highly communicable, especially through direct contact; influenza and measles

83
Q

Horizontal Transfer

A

disease is spread through a population from one infected individual to another (most common)

84
Q

Vertical Transfer

A

From parent to offspring

85
Q

Direct Contact

A

Coughing and sneezing and touching, etc.

86
Q

Indirect Transmission

A

vehicle is involved; injecting infected saliva into blood (mosquito)

87
Q

Nosocomial Infections

A

infections acquired or developed during a hospital stay

88
Q

Koch’s Postulates

A

a series of proofs that became the standard for determining causation of infectious disease

89
Q

Postulate 1

A

Find evidence of a particular microbe in every case of disease

90
Q

Postulate 2

A

Isolate and cultivate microbe in lab; perform full characterization

91
Q

Postulate 3

A

Inoculate susceptible healthy subject with lab culture (poor mice) and observe same result

92
Q

Postulate 4

A

Reisolate the same agent from new subject

93
Q

Epidemiology

A

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

94
Q

Techniques of Epidemiology (3)

A

(1) Track Behaviors; (2) Uses clues on the causative agent; (3) tracks the numbers and distribution of cases

95
Q

Prevalence

A

the total number of existing cases with respect to the entire population; reported as a percentage

96
Q

Incidence (case or morbidity rate)

A

measures the number of new cases over a certain time period (rate and risk of infection)

97
Q

Mortality Rate

A

total number of deaths due to a disease

98
Q

Point-Source Epidemic

A

infectious agent came from a single source, and all of its “victims” were exposed to it from that source (a type of common-source epidemic)

99
Q

Common-Source Epidemic

A

result from common exposure to a single source of infection over a period of time (general term)

100
Q

Propagated Epidemic

A

results from an infectious agent that is communicable from person to person and is sustained over time in a population

101
Q

Index Case

A

the first patient found in an epidemiological investigation (does not have to be the first person infected)

102
Q

Endemic

A

an infectious disease that exhibits a relatively steady frequency over a long time period in a particular geographic location

103
Q

Sporadic

A

occasional cases are reported at irregular intervals at random locales

104
Q

Epidemic

A

when statistics indicate that the prevalence of an endemic or sporadic disease is increasing beyond what is expected for a population (measured in hours to years)

105
Q

Pandemic

A

Spread of epidemic across continents

Microbiology (14 decks)

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