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BACTERIOLOGY - LEC > C3 - General Characteristic of Bacteria > Flashcards

C3 - General Characteristic of Bacteria Flashcards

1
Q

[Prokaryotes or Eukaryotes] contain nucleic acids, proteins, lipids, and carbohydrates

A

Both

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2
Q

[Prokaryotes or Eukaryotes] metabolize food, build proteins, and store energy

A

Both

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3
Q

[Prokaryotes or Eukaryotes] DNA is found in the cell ‘s nucleus, which is separated from the cytoplasm by a nuclear membrane, and the DNA is found in multiple chromosomes

A

Eukaryotes

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4
Q

[Prokaryotes or Eukaryotes] DNA is consistently associated with chromosomal proteins called histones and with nonhistone

A

Eukaryotes

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5
Q

[Prokaryotes or Eukaryotes] Have a number of membrane-enclosed organelles

A

Eukaryotes

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6
Q

[Prokaryotes or Eukaryotes] Cell walls, when present, are chemically simple

A

Eukaryotes

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7
Q

[Prokaryotes or Eukaryotes] Cell division usually involves Mitosis

A

Eukaryotes

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8
Q

[Prokaryotes or Eukaryotes] DNA is not enclosed within a membrane and is usually a singular circularly arranged chromosome

A

Prokaryotes

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9
Q

[Prokaryotes or Eukaryotes] DNA is not associated with histones; other proteins are associated with the DNA.

A

Prokaryotes

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10
Q

[Prokaryotes or Eukaryotes] Lack membrane-enclosed organelles

A

Prokaryotes

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11
Q

[Prokaryotes or Eukaryotes] Usually divide by Binary Fission

A

Prokaryotes

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12
Q

[Prokaryotes or Eukaryotes] Cell walls almost always contain the complex polysaccharide peptidoglycan

A

Prokaryotes

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13
Q

→DNA is copied, and the cell splits into two cells
→involves fewer structures and processes than eukaryotic cell division

A

Binary Fission

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14
Q

How is DNA organized in prokaryotes?

A

Circular chromosome

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15
Q

Are prokaryotic DNA associated with histones?

A

No histones

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16
Q

What is a key characteristic of prokaryotic cell walls?

A

Peptidoglycan

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17
Q

Why is binary fission simpler than eukaryotic cell division?

A

Fewer processes

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18
Q

Where is DNA located in eukaryotes?

A

Nucleus

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19
Q

How is eukaryotic DNA organized?

A

Multiple chromosomes

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20
Q

What proteins are associated with eukaryotic DNA?

A

Histones

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21
Q

Do eukaryotes have membrane-enclosed organelles?

A

Yes

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22
Q

What is the chemical nature of eukaryotic cell walls?

A

Chemically simple

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23
Q

How do eukaryotes typically divide?

A

Mitosis

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24
Q

What key molecules are found in both prokaryotic and eukaryotic cells?

A

Nucleic acids, proteins, lipids, carbohydrates

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25
Q

What processes are similar in both prokaryotic and eukaryotic cells?

A

Metabolism, protein synthesis, energy storage

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26
Q

What is a main structural difference between prokaryotic and eukaryotic cells?

A

Cell walls and membranes

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27
Q

What specialized structures are absent in prokaryotes but present in eukaryotes?

A

Organelles

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28
Q

→unicellular organisms that lack a nuclear membrane and true nucleus

A

BACTERIA

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29
Q

prokaryotes meaning

A

before kernel [nucleus]

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30
Q

classified as prokaryotes, having no mitochondria, endoplasmic reticulum (ER), or Golgi bodies

A

BACTERIA

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31
Q

Bacterial cell wall differences provide the basis for the

A

Gram stain

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32
Q

What characteristics vary in bacterial morphology?

A

Size, shape, arrangement

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33
Q

What is the typical size range for clinically relevant bacteria?

A

0.25 to 1 μm (width), 1 to 3 μm (length)

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34
Q

How does a bacterium compare in size to a virus?

A

Hundreds of times larger

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35
Q

How does a bacterium compare in size to a eukaryotic cell?

A

Ten times smaller

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36
Q

What can cause variation in size and shape within a bacterial population?

A

Asymmetric growth of the cell wall

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37
Q

What do you call bacteria that are circular in shape?

A

Cocci

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38
Q

What do you call bacteria that are ovoid in shape?

A

Coccobacilli

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39
Q

What do you call rod-shaped bacteria?

A

Bacillus

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40
Q

What do you call bacteria with tapered, pointed ends?

A

Fusiform

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41
Q

What do you call helical, corkscrew-shaped bacteria?

A

Spiral

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42
Q

What do you call bacteria that vary in length and number of helical turns?

A

Spirochetes

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43
Q

What do you call bacteria with no defined shape?

A

Pleomorphic

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44
Q

Bacterial Arrangements

A

a. Pairs
b. Chains
c. Grape-like clusters
d. Group of four
e. Packets of eight
f. Palisades
g. Chinese characters

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45
Q

Bacterial shapes

A

Cocci
Coccobacilli
Bacillus
Fusiform
Curved
Spiral
Pleomorphic

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46
Q

What do you call the outermost structure in bacteria?

A

Cell envelope

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47
Q

What membrane is found only in gram-negative bacteria?

A

Outer membrane

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48
Q

What is the bacterial cell wall composed of?

A

Peptidoglycan (murein layer)

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49
Q

What structure, found only in gram-negative bacteria, lies between the outer membrane and the cell membrane?

A

Periplasm

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50
Q

What membrane encloses the cytoplasm of bacterial cells?

A

Cytoplasmic (or cell) membrane

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51
Q

What type of bacteria has an outer membrane?

A

Gram-negative bacteria

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52
Q

What is the primary function of the outer membrane in gram-negative bacteria?

A

Initial barrier to the environment

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53
Q

What does the outer membrane serve as a primary barrier to?

A

Hydrophilic and hydrophobic compounds

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54
Q

What is the outer membrane composed of?

A

Lipopolysaccharide (bilayered structure)

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55
Q

What charge does the surface of gram-negative bacteria have due to the outer membrane?

A

Net negative charge

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56
Q

What role does the outer membrane play in bacterial disease?

A

Significant role in pathogenicity

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57
Q

facilitate the attachment of the outer membrane to the next internal layer in the cell envelope, the cell wall

A

Murein Lipoproteins

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58
Q

→protein structures scattered lipopolysaccharide macromolecules throughout the
→water-filled structures that control the passage of nutrients and other solutes, including antibiotics, through the outer membrane
→influence the extent to which various substances pass through the outer membranes of different bacteria

A

Porins

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59
Q

What is the cell wall also known as in bacteria?

A

Peptidoglycan (or murein layer)

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60
Q

What does the cell wall provide to the bacterial cell?

A

Shape and strength

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61
Q

What does the cell wall protect against?

A

Osmotic pressure changes and mechanical disruption

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62
Q

What is a primary target for the development of antimicrobial agents?

A

Cell wall synthesis and structure

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63
Q

What is the structure of the cell wall composed of?

A

Disaccharide-pentapeptide subunits

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64
Q

What are the alternating sugar components in peptidoglycan?

A

N-acetyl-D-glucosamine and N-acetyl-D-muramic acid (moieties)

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65
Q

How do polymers of peptidoglycan subunits cross-link?

A

peptide bridges

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66
Q

What is formed by the cross-linking of peptidoglycan sheets?

A

Multilayered, cross-linked structure

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67
Q

What is the peptidoglycan structure surrounding the entire bacterial cell called?

A

Murein sacculus (or sack)

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68
Q

How are different types of cell wall structures traditionally categorized?

A

According to staining characteristics

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69
Q

What are the major types of cell walls?

A

Gram-positive and gram-negative

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70
Q

What type of cell wall do mycobacteria have?

A

Acid-fast cell wall

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71
Q

stain gram-positive, have a modified cell wall called an ACID-FAST CELL WALL

A

Mycobacteria

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72
Q

microorganisms that have no cell wall

A

Mycoplasmas

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73
Q

What is the primary component of the gram-positive cell wall?

A

Thick peptidoglycan layer

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74
Q

What are the polysaccharide chains in the gram-positive cell wall made of?

A

N-acetyl-D-glucosamine (NAG) and N-acetyl-D-muramic acid (NAM)

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75
Q

How do many antibiotics affect gram-positive bacteria?

A

By preventing peptidoglycan synthesis

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76
Q

How does the peptidoglycan layer in gram-negative bacteria compare to gram-positive bacteria?

A

Thinner

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77
Q

Why are gram-negative bacteria less affected by certain antibiotics?

A

Different cell wall structure, thinner peptidoglycan

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78
Q

What component of the gram-positive cell wall is anchored to the peptidoglycan?

A

Teichoic acid

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79
Q

What are the polymers in teichoic acid composed of?

A

Glycerol or ribitol phosphate combined with sugars, amino acids, and amino sugars

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80
Q

What is lipoteichoic acid anchored to?

A

Plasma membrane (PM)

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81
Q

What components are unique to the gram-positive cell wall?

A

Teichoic acid and lipoteichoic acid

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82
Q

What other components may be present on the surface of the peptidoglycan layer of gram positive cell walls?

A

Antigenic polysaccharides

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83
Q

→ similar polymers, but the repeat units include sugar acids (eg, N-acetylmannosuronic or d-glucosuronic acid) instead of phosphoric acids

→ synthesized in place of teichoic acids when phosphate is limiting

A

Teichuronic acids

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84
Q

What are the two layers of the gram-negative cell wall?

A

Inner peptidoglycan layer, Outer membrane

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85
Q

What is found outside the peptidoglycan layer in gram-negative bacteria?

A

Outer membrane

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86
Q

What components make up the outer membrane of gram-negative bacteria?

A

Proteins, phospholipids, lipopolysaccharide (LPS)

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87
Q

What are the three regions of lipopolysaccharide (LPS)?

A

O-specific polysaccharide, Core polysaccharide, Lipid A

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88
Q

What is the antigenic region of LPS called?

A

O-specific polysaccharide

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89
Q

What are the components of the core polysaccharide in LPS?

A

Ketodeoxyoctanoic acid (KDO) and heptose

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90
Q

What is the inner, major constituent of LPS also known as endotoxin?

A

Lipid A

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91
Q

How does LPS contribute to the bacterial surface?

A

Negative charge stabilization

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92
Q

What is LPS considered to be due to its effects?

A

Endotoxin

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93
Q

LPS main function

A

Vital in evading the host defenses

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94
Q

→consists of phosphorylated glucosamine disaccharide units to which are attached a number of long-chain fatty acids

→responsible for producing fever and shock conditions in patients infected with gram-negative bacteria

A

Lipid A moiety

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95
Q

What does the lipid A moiety consist of?

A

Phosphorylated glucosamine disaccharide units with long-chain fatty acids

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96
Q

What conditions can the lipid A moiety produce in patients infected with gram-negative bacteria?

A

Fever and shock

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97
Q

What is one function of the outer membrane as a barrier?

A

blocks hydrophobic compounds and harmful substances

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98
Q

How does the outer membrane act as a sieve?

A

Allows water-soluble molecules through porins

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99
Q

What does the outer membrane provide that enhances attachment to host cells?

A

Attachment sites

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100
Q

What role does the strong negative charge of the outer membrane play?

A

Evading phagocytosis

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101
Q

What does the outer membrane act as a barrier to?

A

Toxic substances

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102
Q

Outer membrane function:

A

barrier
sieve
evading phagocytosis

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103
Q

What bounds the periplasmic space in gram-negative bacteria?

A

Internal surface of the outer membrane and external surface of the cellular membrane

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104
Q

What does the periplasmic space contain besides the thin peptidoglycan layer?

A

Murein layer, gel-like matrix with nutrient-binding proteins

105
Q

What is the function of nutrient-binding proteins in the periplasmic space?

A

Assist in the capture of nutrients

106
Q

Found in the periplasmic space that assists in the capture of nutrients

A

nutrient-binding proteins

107
Q

What type of enzymes are found in the periplasmic space?

A

Enzymes involved in degradation of macromolecules and detoxification

108
Q

What does the periplasmic space help detoxify?

A

Environmental solutes and antibiotics

109
Q

What type of cell wall structure do acid-fast bacteria have?

A

Gram-positive

110
Q

What does the acid-fast cell wall contain that is bound to the exterior of the cell wall?

A

Waxy layer of glycolipids and fatty acids (mycolic acid)

111
Q

What percentage of the acid-fast cell wall is lipid?

A

More than 60%

112
Q

What is the major lipid component in the acid-fast cell wall?

A

Mycolic acid

113
Q

How does mycolic acid affect the permeability of the cell wall?

A

Forms a hydrophobic lipid shell, affecting permeability

114
Q

Why is Mycobacterium spp. difficult to stain with the Gram stain?

A

Due to its lipid-rich cell wall

115
Q

What color do Mycobacterium and Nocardia stain with the Gram stain?

A

Faint blue (gram-positive)

116
Q

What type of stain is best for Mycobacterium and Nocardia?

A

Acid-fast stain

117
Q

What do organisms that lack a cell wall contain in their cell membranes?

A

Sterols

118
Q

How does the absence of a cell wall affect the rigidity of these organisms?

A

They lack rigidity

119
Q

What are some examples of organisms without a cell wall?

A

Mycoplasma, Ureaplasma

120
Q

Gram-positive and gram-negative cells can lose their cell walls and grow as_________ in media supplemented with serum or sugar to prevent osmotic rupture of the cell membrane

A

L-forms

121
Q

What is used in media to prevent osmotic rupture of L-forms?

A

Serum or sugar

122
Q

What is the deepest layer of the cell envelope in both gram-positive and gram-negative bacteria?

A

Cytoplasmic (inner) membrane

123
Q

What is the composition of the cytoplasmic membrane?

A

Phospholipid bilayer, proteins (70%)

124
Q

What is a primary function of the cytoplasmic membrane?

A

Osmotic barrier

125
Q

Which organism incorporates sterols like cholesterol into their cytoplasmic membranes?

A

Mycoplasma

126
Q

What functions are performed by the cytoplasmic membrane?

A

Transport, enzyme housing, ATP generation, cell motility, chromosomal segregation, molecular sensing, electron transport, excretion

127
Q

What type of transport relies on diffusion and uses no energy?

A

Passive transport

128
Q

What is an example of passive transport?

A

Simple diffusion, facilitated diffusion

129
Q

What is facilitated diffusion?

A

Selective, no energy, solute concentration outside is never exceeded inside

130
Q

form selective channels that facilitate the passage of specific molecules

A

Channel proteins

131
Q

accounts for the entry of very few nutrients, including dissolved oxygen, carbon dioxide, and water itself

A

Simple diffusion

132
Q

What does active transport move across the cell membrane?

A

Molecules against a concentration gradient using energy

133
Q

What type of transport uses ion gradients for moving molecules?

A

Ion-coupled transport

134
Q

What are the three basic types of ion-coupled transport?

A

Uniport, Symport, Antiport

135
Q

What is the function of uniport transport?

A

Transport of a substrate independent of any coupled ion

136
Q

What does symport transport involve?

A

Simultaneous transport of two substrates in the same direction

137
Q

What does antiport transport involve?

A

Simultaneous transport of two like-charged compounds in opposite directions

138
Q

Which vital cellular processes occur on the cytoplasmic membrane related to the cell wall?

A

Housing enzymes for outer membrane synthesis, cell wall synthesis, and assembly/secretion of extracytoplasmic substances

139
Q

How does the cytoplasmic membrane generate energy for the cell?

A

Through ATP generation

140
Q

What is the role of the cytoplasmic membrane during bacterial replication?

A

Mediates chromosomal segregation

141
Q

How does the cytoplasmic membrane help bacteria respond to environmental changes?

A

It houses molecular sensors that monitor chemical and physical changes

142
Q

What is the function of the cytoplasmic membrane in aerobic species?

A

Electron transport and oxidative phosphorylation

143
Q

What does the cytoplasmic membrane excrete to aid in the breakdown of macromolecules?

A

Hydrolytic exoenzymes

144
Q

What type of transport uses ATP directly to move solutes into the cell?

A

ABC transport

145
Q

In gram-negative bacteria, what facilitates the transport of many nutrients?

A

Specific binding proteins in the periplasmic space

146
Q

In gram-positive bacteria, where are binding proteins located?

A

Attached to the outer surface of the cell membrane

147
Q

What type of metabolism allows bacteria to use energy efficiently by coupling transport with metabolism?

A

Group translocation

148
Q

Why is group translocation not considered active transport?

A

It does not involve a concentration gradient

149
Q

What compounds chelate iron and promote its transport as a soluble complex?

A

Siderophores

150
Q

How do some pathogenic bacteria acquire iron from the host?

A

By binding to host proteins like transferrin and lactoferrin

151
Q

Cytoplasmic structures

A

Ribosomes
Genome
Plasmid
Inclusion Bodies
Endospores/ Asexual spores

152
Q

What is the site of protein biosynthesis in bacteria and gives the cytoplasm a granular structure?

A

Ribosomes

153
Q

What size are bacterial ribosomes?

A

70S (50S, 30S)

154
Q

What antibiotics attach to the 30S ribosomal subunit and interfere with protein synthesis?

A

Streptomycin and Gentamicin

155
Q

What antibiotics attach to the 50S ribosomal subunit and interfere with protein synthesis?

A

Erythromycin and Chloramphenicol

156
Q

What is the bacterial genome made of?

A

A single, circular chromosome

157
Q

What structure is the bacterial chromosome attached to?

A

Mesosome

158
Q

What does the bacterial nucleoid test positive for?

A

Feulgen stain

159
Q

Which bacteria have dissimilar chromosomes compared to the typical single circular genome?

A

Vibrio cholera and Brucella melitensis

160
Q

Extrachromosomal, double-stranded DNA elements associated with virulence

A

plasmids

161
Q

What role do plasmids play in bacterial cells?

A

Code for antibiotic resistance and toxin production

162
Q

Large plasmid provides resistance to what antibiotics

A

β-lactam antibiotics like penicillin

163
Q

Small plasmid is responsible for resistance to

A

tetracyclines and chloramphenicol

164
Q

→Not essential for bacterial growth so a bacterial cell may or may not contain a plasmid

→Sometimes disappears during cell division and it can make bacteria (mostly Gram-neg) pathogenic

A

Plasmid

165
Q

Consists of a single continuous circular molecule ranging in size from 0.58 to almost 10 million base pair Exeptions:

A

Borrelia burgdorferi and Streptomyces coelicolor

166
Q

→Serve as the energy source or food reserve of the bacteria or as a reservoir of structural bulding blocks

A

Inclusions Bodies

167
Q

What is the role of inclusion bodies in bacteria?

A

Serve as energy source or food reserve

168
Q

What are inclusion bodies primarily composed of to lessen osmotic pressure?

A

Polysaccharides

169
Q

What is the storage form of glucose in bacteria?

A

Glycogen

170
Q

What is the storage form for inorganic phosphates in bacteria?

A

Polyphosphate granules

171
Q

What are the phosphate granules in Corynebacterium diphtheriae called?

A

Babes-Ernst bodies

172
Q

What inclusion bodies are found in Yersinia pestis?

A

Bipolar bodies

173
Q

What are the granules found in Mycobacterium tuberculosis called?

A

Much granules

174
Q

→Lipid like compound consisting of chains of B-hyroxybutyric acid units connected through ester linkages →Produced when the source of nitrogen, sulfur or phosphorus is limited and there is excess carbon in the medium

A

Poly-B-hydroxybutyric acid (PHB)

175
Q

Under what condition is poly-B-hydroxybutyrate produced by bacteria?

A

When nitrogen, sulfur, or phosphorus is limited, but carbon is in excess

176
Q

What are PHB and glycogen used as when protein and nucleic acid synthesis resume?

A

Carbon source

177
Q

What kind of granules store hydrogen sulfide and thiosulfate?

A

Sulfur granules

178
Q

Which bacterium has Babes-Ernst bodies?

A

Corynebacterium diphtheriae

179
Q

Which bacterium has bipolar bodies?

A

Yersinia pestis

180
Q

Which bacterium has Much granules?

A

Mycobacterium tuberculosis

181
Q

What are small, dormant structures inside bacterial cells that aid survival?

A

Endospores

182
Q

What substance is an endospore composed of?

A

Calcium dipicolinate

183
Q

Calcium dipicolinate is made of

A

dipicolinic acid and calcium ions

184
Q

Which bacterial genus produces terminal spores?

A

Clostridium tetani

185
Q

Which bacterial genus produces subterminal spores?

A

Clostridium botulinum

186
Q

Which bacterial genus produces central spores?

A

Bacillus anthracis

187
Q

Endospores are produced in what type of bacterial cells?

A

Vegetative cells of some Gram-positive bacteria

188
Q

Endospores are responsible for?

A

perpetuation, but not muliplication

189
Q

Endospores Core are called

A

Spore protoplast

190
Q

What does the core of an endospore contain?

A

A complete nucleus and protein-synthesizing apparatus

191
Q

What is the innermost layer of an endospore that becomes the cell wall of the germinating vegetative cell?

A

Spore wall

192
Q

What is the thickest layer of the spore envelope that contains an unusual type of peptidoglycan?

A

Cortex

193
Q

What is the layer of the endospore composed of keratin-like protein that provides resistance to antibacterial agents?

A

Coat

194
Q

What is the outermost layer of the endospore composed of proteins, lipids, and carbohydrates?

A

Exosporium

195
Q

Exosporium consists of

A

paracrystalline basal layer
hairlike outer region

196
Q

Which bacteria have an exosporium?

A

Bacillus anthracis and Bacillus cereus

197
Q

Cellular Appendages

A

Glycocalyx
Flagella
Pili (Fimbria)

198
Q

What is the outward complex of polysaccharide on the bacterial surface called?

A

Glycocalyx

199
Q

What role does the glycocalyx play for bacteria?

A

Helps the bacteria attach to the surface of solid objects or tissues.

200
Q

How does a capsule differ from a slime layer?

A

A capsule is organized and firmly attached to the cell wall, while a slime layer is unorganized and loosely attached.

201
Q

Where is the capsule located in gram-positive and gram-negative bacteria?

A

Immediately exterior to the murein layer in gram-positive bacteria and

the outer membrane in gram-negative bacteria.

202
Q

What exception exists to the typical polysaccharide capsule composition in bacteria?

A

Bacillus anthracis and Bacillus licheniformis have capsules made of Poly-D-glutamic acid.

203
Q

How does the capsule protect bacteria?

A

It acts as a virulence factor by resisting phagocytosis and desiccation.

204
Q

Why might a capsule need to be removed in laboratory identification?

A

To detect the somatic (cell wall) antigens present.

205
Q

How is capsule removal typically accomplished?

A

By boiling a suspension of the microorganism.

206
Q

Why doesn’t a bacterial capsule stain with common laboratory stains like Gram or India ink?

A

It doesn’t ordinarily stain and appears as a clear “halo”-like area.

207
Q

It can inhibit phagocytosis or aid in the adherence of bacteria to host tissues or synthetic implants.

A

slime layer

208
Q

→Unorganized material that is loosely attached to the cell
wall
→Made up of polysaccharide
→Can either inhibit phagocytosis or aid in the adherence
of the bacteria to the host tissue or synthetic implants
→facilitates and maintains bacterial colonization of
biologic (e.g., teeth) and inanimate (e.g., prosthetic
heart valves) surfaces through the formation of biofilms

A

Slime Layer

209
Q

How does the slime layer contribute to biofilm formation?

A

It facilitates and maintains bacterial colonization on biological (e.g., teeth) and inanimate (e.g., prosthetic heart valves) surfaces.

210
Q

It helps cells attach to their environment and each other, protects the cells, facilitates communication, and enables survival.

A

Extracellular Polymeric Substance (EPS) in biofilms

211
Q

→exterior protein filaments that rotate and cause
bacteria to be motile
→complex structures, mostly composed of the protein
flagellin, intricately embedded in the cell envelope

A

Flagella

212
Q

What protein primarily makes up flagella?

A

Flagellin

213
Q

What is the role of flagella in bacteria?

A

Motility and aiding in disease-causing ability

214
Q

What is the diameter of bacterial flagella?

A

12–30 nm

215
Q

What antigen type is found in flagella?

A

H antigens

216
Q

Which bacteria exhibit gliding motility?

A

Capnocytophaga, Cyanobacteria, Myxobacteria

217
Q

What is the function of the hook in flagella?

A

It connects the basal body to the flagellum.

218
Q

How does the basal body differ between gram-positive and gram-negative bacteria?

A

Gram-positive has one pair of rings, gram-negative has two pairs.

219
Q

What is the filament of the flagellum made of?

A

Flagellin arranged in a helical structure.

220
Q

What is bacterial motility?

A

Movement through “runs” and “tumbles.”

221
Q

What causes a “tumble” in bacterial movement?

A

Reversal of flagellar rotation

222
Q

What unique movement ability does Proteus have?

A

Swarming across solid media.

223
Q

endowed with many flagella
→ can “swarm,” or show rapid wavelike movement
across a solid culture medium

A

Proteus

224
Q

bacterium moves in one direction
for a length of time

A

“Run” or “Swim”

225
Q

What is the term for bacteria without flagella?

A

Atrichous

226
Q

What is the term for bacteria with a single flagellum at one end?

A

Monotrichous

227
Q

What is the term for bacteria with a single flagellum at both ends?

A

Amphitrichous

228
Q

What is the term for bacteria with a tuft or group of flagella at one or both ends?

A

Lophotrichous

229
Q

What is the term for bacteria with flagella covering the entire surface?

A

Peritrichous

230
Q

What are the bundles of fibrils that spiral around a spirochete cell called?

A

Axial filaments

231
Q

What is the location where axial filaments are anchored in spirochetes?

A

One end of the spirochete

232
Q

What type of movement is produced by the rotation of axial filaments in spirochetes?

A

Spiral motion

233
Q

What bacterial movement is similar to how a corkscrew moves through a cork?

A

Axial filament movement

234
Q

What group of bacteria move using axial filaments or endoflagella?

A

Spirochetes

235
Q

Which method is best for observing true motility and Brownian movement?

A

Hanging drop method

236
Q

What term describes bacteria moving in a definite direction?

A

True motility

237
Q

What type of movement occurs when bacteria bounce back and forth due to water molecules?

A

Brownian movement

238
Q

What is the term for bacterial movement toward or away from a stimulus?

A

Taxis

239
Q

What method is best for observing motility and includes using a hanging drop?

A

Hanging drop method

240
Q

Ways of demonstrating motility in the Lab:

A

✓Hanging Drop Method
✓SIM
✓Flagellar staining
✓Serologic test
✓Fluorescent Antibody Technique(FAT)
✓Swarming Phenomenon
✓Darkfield Microscopy

241
Q

What laboratory test is used for motility and involves sulfur, indole, and motility testing?

A

SIM

242
Q

Which technique uses stains to visualize bacterial flagella?

A

Flagellar staining

243
Q

Which test involves antibodies to detect bacterial motility?

A

Serologic test

244
Q

What method uses antibodies tagged with fluorescent dyes to detect bacteria?

A

Fluorescent Antibody Technique (FAT)

245
Q

What phenomenon involves the movement of bacteria across solid media?

A

Swarming phenomenon

246
Q

Which microscopy method helps visualize bacterial motility in the lab?

A

Darkfield microscopy

247
Q

What are hairlike structures that help bacteria attach to host cells called?

A

Pili (Fimbriae)

248
Q

What protein makes up the structural subunits of pili?

A

Pilin

249
Q

What is the type of motility involving jerky, intermittent movements due to pilus retraction?

A

Twitching motility

250
Q

What kind of pili are involved in bacterial adherence to surfaces and contribute to virulence?

A

Common pili (Ordinary pili)

251
Q

What is the term for the specialized pilus that transfers DNA during bacterial conjugation?

A

Sex pilus

252
Q

Which bacterial cells produce the protein F factor for conjugation?

A

F-positive cells

253
Q

In which bacteria are fimbriae the site of the M protein, the main surface antigen?

A

Streptococci

254
Q

What acid associated with fimbriae helps group A streptococci adhere to epithelial cells?

A

Lipoteichoic acid

255
Q

What bacteria can produce pili of different antigenic types?

A

Neisseria gonorrhoeae

256
Q

→hairlike, proteinaceous structures that extend
from the cell membrane into the external
environment; some may be up to 2 μm long
→Hair-like microfibrils usually produced by
flagellated Gram-negative bacteria observable
by electron microscopy
→serve as adhesins that help bacteria attach to
animal host cell surfaces, often as the first step in
establishing infection

A

Pili (Fimbria)

257
Q

Examples of bacteria with twitching motility due to powerstroke

A

Pseumdomons aeruginosa, Neisseria gonorrheae,
and some strains of E. coli

258
Q

→present only in cells that produce a protein referred to
as the F factor

A

Sex pilus

BACTERIOLOGY - LEC (15 decks)

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