Brainscape's Knowledge GenomeTM

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


See full index

infection and immunity > bacteria > Flashcards

bacteria Flashcards

1
Q

What is the human microbiome?

A

Microbes that live on and within the human body.

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

What can cause “bad” pathogens to arise within the microbiome?

A

Disturbances.

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

What disturbances can cause “bad” pathogens to arise within the microbiome?

A

dietary changes, stress, and antibiotics.

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

How can pathogens enter our body from the environment?

A

Through contact with surfaces we touch or other organisms.

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

True or False: The majority of microbes are non-pathogenic.

A

True

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

What are examples of methods used to protect against pathogens?

A

Vaccinations, antibiotics, and public health changes (e.g., improved sanitation).

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

What are host defense mechanisms?

A

Body’s protections against pathogens, like barrier immunity (skin/mucous) and T regulatory (Treg) cells.

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

How do pathogens adapt over time to survive?

A

They adapt by losing or gaining traits that improve their survival.

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

What is the first step for pathogens to infect the body?

A

They need to break through body barriers.

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

How can pathogens enter through the skin?

A

By exploiting skin conditions, such as acne or eczema.

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

What pathogens break through epithelium in the respiratory system?

A

Influenza

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

What pathogens break through Immunoglobulins in mucous secretions?

A

Tuberculosis

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

What pathogens break through stomach acidity?

A

Food poisoning and Cholera

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

What pathogens that pass through sphincter in urinary bladder?

A

Bacteria causing UTI

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

What is the incubation period?

A

The time from when a pathogen enters the body to when the first symptom appears.

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

What factors affect the length of the incubation period?

A

Health of the host
Growth rate of the pathogen
Degree of exposure to the pathogen

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

What characterizes an acute infection? Example?

A
  • Quick symptom and fast recovery.
  • The host gains immunity against reinfection. (ex strep throat)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What characterizes a chronic (persistent) infection? Example?

A

Slow symptom development, and it can last for months to years. (ex tuberculosis)

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

What characterizes a latent (persistent) infection? Example?

A

The illness never goes away, becoming dormant in the body, and can be reactivated when immunity is low. (ex syphilis, typhoid fever)

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

What is a carrier in the context of latent infections?

A

A carrier is a host who does not show symptoms but can still spread the infection to others.

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

How can pathogens be transmitted from person to person?

A

Through horizontal transmission:

Blood
Saliva
Genital secretions (e.g., STDs)
Respiratory droplets
Urine
Stool

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

How can pathogens be transmitted from mother to baby?

A

Through vertical transmission:

Breast milk
Delivery
Placenta

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

What is a vector in pathogen transmission?

A

an animal or arthropod that transmits pathogens, such as the rabies virus through an animal bite.

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

What is virulence?

A

The degree of pathogenicity(capacity) of a pathogen (bacteria, fungi, or virus).

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

How is virulence determined?

A

By the pathogen’s ability to invade and multiply within the host, causing disease.

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

What do pathogens do to the host?

A

They grow and thrive at the expense of the host.

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

What is a strict pathogen?

A

A pathogen that always causes disease when it infects a host.

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

Give examples of strict pathogens.

A

Mycobacterium tuberculosis (causes tuberculosis)
Plasmodium species (cause malaria)
Rabies virus (causes rabies)

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

What is an opportunistic pathogen?

A

A pathogen that is part of the normal microbial flora

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

When do opportunistic pathogens cause disease?

A

When there is a weakened immune system, disruption in microbial flora, or a breached barrier (e.g., a wound).

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

What maintains the shape of bacteria?

A

The cell wall, which is composed of peptidoglycan.

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

Do bacteria have a nucleus?

A

No

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

What type of cells are bacteria?

A

prokaryotic cells, meaning they have no membrane-bound organelles.

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

What structure does the bacterial chromosome form?

A

nucleoid

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

How small are bacteria?

A

tiny

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

What are the three main shapes of bacteria?

A

Cocci (spherical)
Bacilli (rod-shaped)
Spiral (spiral-shaped)

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

What is a pleomorphic bacteria?

A

No characteristic shape and can change their shape, or have a combination of shapes.

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

What shape are cocci bacteria?

A

Spherical bacteria.

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

What are clusters of cocci bacteria called?

A

Staphylococcus

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

What is a single cocci called?

A

coccus

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

What do you call two cocci bacteria together?

A

diplococcus

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

What are chains of cocci bacteria called?

A

Streptococcus

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

What is a group of four cocci bacteria called?

A

Tetrad

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

What is a cube of eight cocci bacteria?

A

sarcina

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

What shape are bacilli bacteria?

A

Rod-shaped bacteria.

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

What do you call two bacilli bacteria together?

A

diplobacillus

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

What is a single bacilli called?

A

bacillus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

What are chains of bacilli bacteria called?

A

Streptobacilli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

What is the term for bacilli arranged in a parallel arrangement?

A

Palisades

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

What is a coccobacillus?

A

shape intermediate between a coccus (spherical) and a bacillus (rod-shaped).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

What shape is a vibrio bacteria?

A

A curved or comma-shaped rod.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

What is a spirillum bacteria?

A

A thick, rigid spiral-shaped bacteria.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

What is a spirochete bacteria?

A

A thin, flexible spiral-shaped bacteria.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

What happens to Gram-positive bacteria during the Gram stain procedure?

A

bacteria retain crystal violet from iodine and appear purple.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

What happens to Gram-negative bacteria during the Gram stain procedure?

A

bacteria do not retain crystal violet, appearing transparent or pink after counterstaining.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

What is lipopolysaccharide (LPS)?

A

Found only in Gram-negative bacteria
Made up of lipid and carbohydrate
Helps bacteria cause diseases

55
Q

What is the structure of the cell wall in Gram-positive bacteria?

A

thick peptidoglycan layer

55
Q

How many structural domains does lipopolysaccharide (LPS) have?

A

3 structural domains.

56
Q

What is peptidoglycan?

A

Component of bacterial cell walls
Made of sugar and amino acids.

57
Q

Why don’t Gram-negative bacteria retain crystal violet stain?

A

They lack peptidoglycan in sufficient amounts to retain the crystal violet.

58
Q

What structure in Gram-negative bacteria prevents the crystal violet stain from being retained?

A

The outer membrane

59
Q

Why are Gram-negative bacteria more resistant to antibiotics?

A

They have an impenetrable cell wall

60
Q

How do Gram-negative bacteria develop resistance more quickly?

A

Due to their outer membrane and more complex cell wall.

61
Q

Can all bacteria be reliably classified using the Gram stain?

A

No

62
Q

How do acid-fast bacteria appear after Gram staining?

A

may appear purple after Gram staining, although they are not closely related to Gram-positive bacteria.

62
Q

What is characteristic of acid-fast bacteria?

A

cell walls that retain stains particularly well.

63
Q

What happens when Gram-variable bacteria are stained?

A

show a mix of pink and purple cells

64
Q

What are acidophiles?

A

Bacteria that grow at highly acidic conditions
pH values around 2

65
Q

What are alkalophiles?

A

bacteria that only grow well in highly alkaline conditions
pH values near 10

66
Q

What are aciduric bacteria?

A

bacteria able to survive acidic conditions
dont necessarily grow under those conditions.

67
Q

What are psychrophiles?

A

Prokaryotes that only grow well at temperatures bellow 15°C (cold-loving bacteria).

68
Q

What are thermophiles?

A

bacteria that thrive at very high temperatures, around 100°C.

69
Q

What are the Bacterial Cell Structures?

A

Capsule
Cell Wall
Cytoplasmic Membrane
Pili
Flagella
Nucleoid
Cytoplasm
Ribosomes

70
Q

How does the capsule help bacteria attach to host tissues?

A

mediates the attachment of bacteria to host tissues, such as heart valves and catheters.

71
Q

What is the composition of the bacterial capsule?

A

polysaccharides

71
Q

What does the capsule cover in bacteria?

A

outer layer of the cell wall.

72
Q

How does the capsule act as a virulence factor?

A

can inhibit phagocytosis by neutrophils and macrophages, making it a virulence factor for some bacteria.

73
Q

What is Streptococcus mutans?

A

one of the causative agents of dental caries.

74
Q

How does Streptococcus mutans attach to tooth surfaces?

A

via a capsule.

75
Q

What is the slime layer in bacteria?

A

a loosely adherent colloidal material that some bacteria secrete.

76
Q

Which type of bacteria have pili and fimbriae?

A

Gram-negative bacteria

76
Q

How does the slime layer compare to the capsule?

A

usually similar to the capsule but is more loosely attached.

77
Q

What are pili in bacteria?

A

long, hair-like tubular microfibers that extend from the cell surface.

78
Q

What are fimbriae in bacteria?

A

bristle-like, short fibers that help with attachment and motility.

79
Q

What are the functions of pili and fimbriae?

A

responsible for attachment, transfer of DNA, and motility in bacteria.

80
Q

Where do flagella extend from in bacteria?

A

extend from the interior cell body of bacteria.

81
Q

What is the function of flagella in bacteria?

A

Motility

82
Q

What else can flagella sense besides temperature?

A

Certain chemicals and metals.

83
Q

Which types of bacteria have flagella?

A

Both Gram-positive and Gram-negative bacteria

84
Q

What are the Bacterial Growth Curve Phases?

A

Lag Phase
Exponential (Log) Phase
Stationary Phase
Death Phase

85
Q

What is the Lag Phase in bacterial growth?

A

the initial phase where bacteria are active but not dividing.

86
Q

What happens to bacteria during the Lag Phase?

A

bacteria increase in size, but cell division does not occur.

87
Q

What happens during the Exponential (Log) Phase of bacterial growth?

A

cells divide by binary fission and double in numbers.

88
Q

What is the metabolic activity like during the Exponential (Log) Phase?

A

high

89
Q

When are antibiotics and disinfectants most effective against bacteria?

A

Exponential (Log) Phase, when bacteria are rapidly dividing.

90
Q

What happens during the Stationary Phase of bacterial growth?

A

bacterial cell growth reaches a plateau, where the number of dividing cells equals the number of dying cells.

91
Q

Is there overall population growth during the Stationary Phase?

A

No, because the rate of cell division equals the rate of cell death.

92
Q

What happens to the number of living cells during the Death Phase?

A

number of living cells decreases exponentially

93
Q

What happens to the bacterial population during the Death Phase?

A

experiences a sharp decline in numbers

94
Q

Which type of bacteria can form spores?

A

Only some Gram-positive bacteria form spores.

95
Q

Why do Gram-positive bacteria form spores?

A

to survive adverse environmental conditions.

96
Q

How does the structure of a bacterial spore help it?

A

protects its DNA from intense heat, radiation, and chemical agents.

97
Q

What do aerobic bacteria require for survival, growth, and reproduction?

A

Oxygen

98
Q

Why are bacterial spores difficult to eliminate?

A

highly resistant to environmental factors and are difficult to decontaminate with standard disinfectants or even autoclaving.

99
Q

Do anaerobic bacteria need oxygen to grow?

A

No

100
Q

Obligate aerobe

A

growth only at the surface

101
Q

Facultative anaerobe

A

growth throughout, often heavier growth towards the top

102
Q

Obligate anaerobe

A

growth only at the bottom

103
Q

Aerotolerant anaerobe

A

relatively low growth throughout

104
Q

Microaerophile

A

growth just below the surface

105
Q

What molecule is involved in bacterial metabolism?

A

Glucose

106
Q

What is glycolysis in bacterial metabolism?

A

Glucose is converted
Occurs in both aerobic and anaerobic conditions.

107
Q

What is fermentation in bacterial metabolism?

A

Occurs under anaerobic conditions
Involves the conversion of pyruvate to various end products, such as ethanol and lactic acid.

108
Q

How do cell wall components affect the immune system?

A

help alarm the immune system by triggering responses

109
Q

What component in Gram-positive bacteria’s cell wall activates the immune system?

A

Peptidoglycan can induce fever and inflammation.

110
Q

What cell wall component in Gram-negative bacteria helps alarm the immune system?

A

Lipopolysaccharide (LPS) helps alarm the immune system by releasing endotoxins.

111
Q

What effects do low doses of endotoxins from LPS have on the body?

A

activate the immune response and can trigger fever.

112
Q

What effects do high doses of endotoxins from LPS have on the body?

A

can cause extreme fevers, septic shock, and skin lesions, which may be fatal.

113
Q

What is one way bacteria cause disease?

A

Release exotoxins to damage the host.

114
Q

What are exotoxins

A

receptor-binding proteins

114
Q

How else can bacteria cause disease besides releasing exotoxins?

A

Can inhibit phagocytosis by immune cells, preventing them from being destroyed.

115
Q

What effect do exotoxins have on host cells?

A

cause cell death or alter cell function.

116
Q

What is cytolysis in the context of exotoxins?

A

the bursting of a host cell due to osmotic pressure, caused by exotoxins.

117
Q

Can both Gram-positive and Gram-negative bacteria produce exotoxins?

A

Yes both

118
Q

What substances can exotoxins release?

A

enzymes, gas, acids, and toxins.

119
Q

What effects can exotoxins have on host cells?

A

can cause cell lysis and tissue degradation through immune response.

120
Q

Transformation

A

Introductions, uptake and expression of foreign genetic material

121
Q

How are exotoxins encoded?

A

on a plasmid or a bacteriophage.

122
Q

Conjugation

A

Transfer of DNA via a plasmid from a donor cell to a recipient cell

123
Q

Transduction

A

Bacterial DNA is moved from one bacterium to another by a virus

124
Q

What is quorum sensing in bacteria?

A

bacteria’s communication with each other to coordinate behaviors based on their population density.

125
Q

How does the location of the infection affect its severity of the Pathogenic Bacteria?

A

can vary depending on the location, such as the Central Nervous System (CNS), which can be more critical.

126
Q

How does the Gram stain type affect the severity of an infection?

A

Gram neg and positive bacteria have different characteristics and responses to treatment.

127
Q

How does the number of bacterial strains affect infection severity?

A

Some bacteria require fewer than 200 strains to cause infection
Others need larger number of strains to have same effect

128
Q

Does the host’s immune status impact the severity of the infection?

A

Yes, an immunocompromised host is more likely to experience a severe infection.

129
Q

Why are fungal infections harder to treat?

A

closely related to human cells, making treatment difficult.

130
Q

Why are viruses hard to treat?

A

live inside our cells, making them hard to target.

131
Q

Why are bacteria easier to treat?

A

foreign pathogens with distinct features, making them easier to recognize and target.

132
Q

How do vaccines help immunity?

A

Stimulate immune system to produce antibodies and memory cells without causing disease.

infection and immunity (7 decks)

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