Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Completed > Ch 13 Microbe-Human Interactions > Flashcards

Ch 13 Microbe-Human Interactions Flashcards

(78 cards)

Start Studying
0
Q

Commensalism

A

An interaction between two species in which one benefits and the other is neutral (not harmed not benefited)
Ex: normal flora

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

Mutualism

A

An interaction between two species in which both benefit. Ex: normal flora

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

Parasitism

A

An interaction between two species in which one benefits at the expense or harm to the other

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

Name the four stages of disease

A

Contact, colonization, infection, disease

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

Define contact

A

When exposed to the microbe. can be direct or indirect

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

Does every exposure lead to colonization

A

No

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

Explain colonization

A

Bacteria is implanted in or on the host as colonies; start to increase growth

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

Explain infection

A

The pathogenic bacteria penetrate host defenses, enter the tissues, and multiply; rapid increase in growth

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

Explain disease

A

The disruption of a tissue or organ caused by microbes or their products; growth leads to harm. Ongoing process with a deterioration in health, possible death

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

Another term for normal flora

A

Resident biota

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

Describe skin flora

A

Skin is dry salty; in general gram + bacteria; typically large cocci, xerophile, halophile; ex: strep & staph

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

Describe the oral flora

A

Over 30 different species; mixture of aerobic, facultative and obligate anaerobic. Ex: lysozyme in saliva

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

Describe Gastrointestinal flora numbers

A

Stomach has very few species due to high acidity; small intestine has a large number due to pH 7; colon Has an even larger number

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

Examples of G.I. Flora and oxygen requirements

A

E. coli, salmonella; Colon has 300:1 anaerobes:facultatives

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

Examples of typical upper respiratory flora

A

Strep and staph

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

Is the lower respiratory tract sterile or unsterile

A

Sterile

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

Microbial antagonism

A

The antagonistic effect that good microbes have against intruder microbes

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

Endogenous infection

A

Caused by normal flora that are already present in the body that are introduced to a site that should be sterile or is not where it should be. Ex: UTI caused by E. coli

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

Another term for endogenous infection

A

Opportunistic

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

Define pathogen

A

A microbe whose relationship with the host is parasitic

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

Pathogenicity

A

The microbes potential to cause infection and disease

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

Virulence

A

The degree of pathogenicity

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

Three ways to measure virulence

A

Infectivity, invasiveness, toxigenicity

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

What is infectivity

A

The ability to establish itself in the host

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
What is invasiveness
The ability to spread in the host
25
What is toxigenicity
The ability to cause damage
26
What is the number one line of defense for a person against microbes
Normal flora
27
A true pathogen can cause disease _____
in a healthy person with a normal immune system
28
An opportunistic pathogen can cause disease ____
only when the host defenses are compromised or if they become established in a part of the body that is not natural to them
29
How are pathogens classified
By using biosafety levels. Levels are 1, 2, 3 and 4 (with 4 being the worst)
30
What is the first step in The stages of disease progression
getting in, starts with the portal of entry: The microbe enters the tissues through the characteristic route
31
Name the 4 types of portals of entry
Skin, G.I. tract, respiratory tract, urogenital tract
32
What is an infectious dose
Minimum number of microbes to cause an infection. Numbers below that will generally not cause an infection
33
What is step 2 of the four stages of disease progression
attaching to the host; adherence
34
Name 4 things that help microbes with adhesion
Fimbriae, slime layer, capsule, viral spikes
35
Define adhesion
Process by which microbes game a more stable foothold on host tissues
36
What is the 3rd step in the stages of disease progression
surviving host defenses (the host, not normal flora!!)
37
Name 4 factors that help bacteria resist phagocytosis
Leukocidins, capsules, coagulase, hiding in the host (intracellular parasite)
38
What are leukocidins
Substances released by bacteria that are toxic to white blood cells
39
Pyogenic
Pus forming bacteria, strep and staph are famous for this
40
Explain how capsules are anti-phagocytic factors
Help bacteria to stick better and is similar enough to self cell that the phagocytes ignore it
41
Explain how coagulase is an anti-phagocytic factor and give one example of a bacteria that has it
Causes human molecules to clot and cover it up. Ex: staph aureus
42
Explain how an intracellular parasite resists phagocytosis and give 2 examples of bacteria that do this
parasite is phagocytized then the bacteria stays hidden in white blood cells not being killed, "hiding" Ex: TB and malaria
43
Name five digestive enzymes produced by microbes
Mucinase, keratinase, collagenase, hyaluronidase, and fibrinolysin (aka: kinase)
44
What does hyaluronidase do
Digests the hyaluronic acid (ground substance) between your cells; digests the glue between your cells
45
Name five bacterial toxins
Neurotoxin, enterotoxin, hemotoxin, nephrotoxin, respiratory toxin
46
Which hemotoxin causes beta hemolysis
Alpha toxin
47
What is more damaging digestive enzymes or bacterial toxins
Bacterial toxins
48
Endotoxin
Gram - bacteria; in certain genera the lipopolysaccharide (LPS) is the endotoxin
49
How do endotoxins affect a cell
They are not secreted only released when a cell dies and sheds its outer membrane
50
Describe symptoms of endotoxins
Cause fever, pyrogenic, inflammation, hemorrhage, diarrhea. Could lead to endotoxic shock (aka toxic shock) symptoms tend to be more systemic
51
Name 4 genera of endotoxin formers and describe their shape
Salmonella, Shigella, Escherichia are all gram - rods | Neisseria is gram - cocci
52
Endotoxins are typically toxic at what type of concentration (hi or low)
Typically only at high concentrations | 200-400 mg/ml
53
What effect does he have on endotoxins
No matter how long you "cook" it these are stable at high temperatures
54
How do exotoxins affect a cell
Are secreted by the bacteria cell, have very specific actions. Tend to travel well
55
Exotoxins are typically toxic at what type of concentration (hi or low)
Toxic at low concentrations (micrograms per milliliter)
56
Name two types of neurotoxic exotoxins
Clostridium tetani and clostridium botulinum
57
What does Clostridium tetani cause
Acts at neuromuscular junction causing spastic paralysis
58
What does Clostridium botulinum cause
Act at neuromuscular junction causing flaccid paralysis
59
How does bordetella pertussus work
Inactivates respiratory cilia
60
What does vibrio cholera do
Causes extreme salt and water loss from intestinal cells
61
Describe a focal infection
Infectious agent breaks loose from local infection and is carried into other tissues. Ex: scarlet fever from strep throat
62
Example of a localized infection
Wart, pimple
63
Example of a systemic infection
Chickenpox
64
Another phrase for mixed infection
Polymicrobial
65
Name the four stages of clinical infection
Incubation period, prodromal period, Invasive period, Convalescent period
66
The height of an infection occurs during which stage of infection
Invasive period
67
Septicemia
Microbes are **multiplying** in the blood and are present in large numbers
68
Bacteremia
Small numbers of bacteria are found in the blood but are **not multiplying**
69
Passive carrier
Does not become infected but can transmit to others. Ex: typhoid Mary
70
Asymptomatic vs symptomatic carrier
Infected but shows no symptoms | Infected and shows symptoms
71
Biological vs mechanical vectors
B: necessary for parasite to survive ex: mosquitos to malaria M: aren't infected, just carries it on the outside of its body from place to place.
72
Zoonosis
Resides in animals and can cross species. Ex: rabies, HIV
73
4 types of direct transmission
Contact, droplet, vertical, biological vector
74
3 types of indirect transmission
By vehicle, fomite, or fecal-oral route
75
Endemic
Cases are concentrated in one area at a relatively stable rate
76
Epidemic
Increased number of cases that often appear in geographical clusters; rapid increase
77
Pandemic
Epidemic ranges over more than one continent

Completed (12 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions