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1
Q

T/F bacteria are the smallest living cells

A

True

2
Q

T/Fbacteria range from 0.1 to 10 um

A

True

3
Q

Are there cytoplasmic organelles in bacteria

A

no

4
Q

Do gram - or gram + have an outer membrane

A

gram negative

5
Q

T/F a capsule is part of a cell envelope

A

false

6
Q

T/f the envelope of gram negative bacteria contain an outer membrane

A

true

7
Q

does the cell membrane of bacteria contain sterols

A

no

8
Q

what is the only bacteria that contain sterols

A

mycoplasma

9
Q

T/F the cell membrane is not permeable

A

false, it is semi permeable

10
Q

Does cell membrane contain more lipids or proteins?

A

It is semi-permeable; consists of 70% protein and 30% phospholipid.

11
Q

Where is the electron transport system located in bacteria ?

A

cell membrane

12
Q

the mitochondria in eukaryotic cells is synonomous with what structure in bacteria

A

cell wall

13
Q

proteins that function in chemotaxis and transport are located on what region of the cell

A

cell wall

14
Q

T/F The cytoplasmic membranes of gram-positive and gram-negative cells are similar in composition and
function.

A

True

15
Q

Do gram positive or gram negative bacteria have an outer membrane

A

gram negative

16
Q

What is the function of the outer membrane

A

it is an asymmetric lipid bilayer providing protection to the cell;

17
Q

What composes the outer and inner layer of the outer membrane

A

outer most layer of outer membrane is composed of lipopolysaccharide (LPS) and
is called endotoxin; inner layer of outer membrane is composed of phospholipid

18
Q

another word for endotoxin is

A

LPS

19
Q

Do gram positive or gram negative bacteria have LPS

A

Gram negative . ( remember its only on gram negative because they have an outer membrane )

20
Q

outer membrane proteins are known as

A

porins

21
Q

T/F Outer membrane proteins (porins) allow for diffusion of small hydrophobic molecules through the membrane

A

False! Outer membrane proteins (porins) allow for diffusion of small hydropHILLIC
molecules through the
membrane

22
Q

What 3 things make up LPS ?

A
  • LPS consists of 3 component parts: somatic O antigens, core polysaccharide and Lipid A.
23
Q

somatic O antigens, core polysaccharide and Lipid A. make up what structure?

A

LPS

24
Q

What is responsible for the toxity of LPS

A

Lipid A

25
Q

What is responsible for distinguish serotypes of a species and responsible for the antigenicity of LPS?

A

Somatic O antigens

26
Q

What are some Pathophysiologic effects of LPS

A

Pathophysiologic effects of LPS include fever (pyrogenic) and shock; B cell activation; the release of cytokines from macrophages; Shwartzman reaction, and death from massive organ dysfunction

27
Q

What 2 sugars make up peptodiglycan ?

A

N-acetylglucosamine and N-acetylmuramic acid.

28
Q

A tetrapeptide is attached to

N-acetylmuramic Acid or N-acetylglucosamineacid residue?

A

N-acetylmuramic Acid

29
Q

Name 2 functions of peptodiglycan

A

peptidoglycan protects cells from osmotic lysis and provides cell shape.

30
Q

about how many layers peptodiglycan do we see in gram positive bacteria

A

40

31
Q

how about many layers of peptodiglycan do we see in gram negative bacteria

A

1-2 layers

32
Q

Name 2 places where we can see lysozyme

A

tears and saliva

33
Q

What enzyme can disrupt NAG & NAM

A

lysozyme

34
Q

what are the 3 locations that peptodiglycan biosnthesis takes place

A

cytoplasm, membrane, and the wall

35
Q

another word for cross linking is …

A

transpeptidation

36
Q

another word for transpeptidation is

A

crosslinking

37
Q

another word for penicillin binding proteins is

A

Transpeptidases

38
Q

inhibition of transglycosylation and transpeptidation is caused by

A

vancomycin

39
Q

what does vancomycin do

A

inhibits transglycosylation and transpeptidation

40
Q

_________ insert newly made peptidoglycan
monomers into pre-existing peptidoglycan in the wall and links together NAG and NAM residues by β 1,4
linkages

A

transglycosidases insert newly made peptidoglycan
monomers into pre-existing peptidoglycan in the wall and links together NAG and NAM residues by β 1,4
linkages

41
Q

What kind of linkages do we see in NAG & NAM

A

β 1,4

42
Q

name an enzyme that can disrupt the linkage between NAG and NAM residues.

A

Lysozyme (in tears, saliva)

43
Q

T/F Peptidoglycan biosynthesis takes place in 3 locations: cytoplasm, membrane, and the wall.

A

True!

44
Q

List 2 things that inhibit transpeptidation

A

penicillin and cephalosporins;

45
Q

What is transglycosilation

A

insertion of newly made peptidoglycan

monomers into pre-existing peptidoglycan

46
Q

T/F vancomycin inhibits transglycosylation and transpeptidation;

A

True

47
Q

What does vancomyocin inhibit

A

transglycosylation and transpeptidation;

48
Q

a membrane phospholipid which translocates newly made peptidoglycan across the
Membrane to be inserted into pre-existing peptidoglycan is known as …

A

Bactoprenol

49
Q

regeneration of bactoprenol phosphate from bactoprenol pyrophosphate is inhibited by what antibiotic

A

Bacitracin

50
Q

list 3 wall-less bacteria

A

Wall-less bacteria include: Mycoplasma sp. and protoplasts and spheroplasts;

51
Q

are protoplasts derived from gram + or gram - bacteria

A

gram positive

52
Q

describe how protoplasts are generated

A

protoplasts are derived from

gram-positive bacteria when treated with penicillin and lysozyme under hypertonic conditions;

53
Q

are spheroplasts derived from gram positive or gram negative bacteria

A

gram negative

54
Q

Are teichoic acids found on gram + or gram -

A

Teichoic acids are found in gram-positive bacteria only and

55
Q

T/F Teichoic acids are found on both gram + /-

A

FALSE! only found on gram positive

56
Q

are teichoic acids found on NAG or NAM?

A

NAM

57
Q

list 2 things that teichoic acids play a role in

A

involved in cell adhesion, activation of complement, and are antigenic.

58
Q

mediate adherence/attachment of bacteria to host cells; most important virulence factor for Neisseria
gonorrhoeae. What cell surface component is this?

A

Pilli

59
Q

T/F Pili undergo phase variation and antigenic variation; important in the evasion of host immune system.

A

True!

60
Q

– role in cell adherence; prevents phagocytosis (anti-phagocytic); most important virulence factor for Streptococcus pneumoniae; consists of K antigens. What cell surface structure is this?

A

Capsule

61
Q

What is the quellung reaction?

A

The Quellung reaction is used to detect the presence of capsules on cells.

62
Q

What is the name of the reaction that is used to determine the presences of a capsule on a cell ?

A

The Quellung reaction

63
Q

Mediate cell motility and movement during (chemotaxis) which is the movement of bacteria in specific directions in response to environmental stimuli. What cell surface structure is this?

A

Flagella

64
Q

T/F Flagella are antigenic and consist of K antigens;

there is a simple 2 component signaling pathway involved in chemotaxis.

A

FALSE! They have H ANTIGENS, the CAPSULE has K antigens

65
Q

breakdown of glucose in the absence of oxygen is known as

A

Fermentation

66
Q

How many ATP are generated in Lactic Acid Fermentation?

A

2 ATP

67
Q

How many ATP are generated in mixed acid fermentation

A

3 ATP

68
Q

How many ATP are generated in lactic acid fermentation

A

2 ATP

69
Q

What is the mechanism of energy generation in fermentation

A

substrate level

70
Q

In general most fermentations generated how much ATP

A

2

71
Q

-breakdown of glucose in the presence of oxygen is known as

A

-Aerobic respiration

72
Q

a PO ratio of 3 generates how many ATP in bacteria undergoing aerobic respiration

A

38 ATP

73
Q

A PO ratio of 2 will generate how many ATP undergoing aerobic respiration

A

26 ATP

74
Q

The mechanism of energy generation in Aerobic respiration is

A

Oxidative phosphorylation

75
Q

What is the terminal electron acceptor in Aerobic respiration

A

Oxygen is the terminal electron acceptor.

76
Q

energy released during electron transport ,which is

used by the cell to make ATP is known as …

A

Proton motive force (pmf)

77
Q

the number of ATPs generated per oxygen atom consumed or ratio of phosphates incorporated into
ATP to oxygen atoms reduced to water this ratio of known as

A

P/0 ratio

78
Q

more efficient than fermentation but less efficient than aerobic respiration because
fewer ATPs are produced; compounds other than oxygen are used as terminal electron acceptors (nitrate,
sulfate). This is known as..

A

-Anaerobic respiration

79
Q

The bacteria that are pathogenic to man are known as

A

-Heterotrophs

80
Q

bacteria that require organic form of carbon (glucose) are considered

A

-Heterotrophs

81
Q

bacteria that use inorganic form of carbon (CO2) are considered

A

autotrophs

82
Q

give an example of inorganic carbon

A

co2

83
Q

give an example of organic carbon

A

glucose

84
Q

give an example of inorganic carbon

A

c02

85
Q

strict aerobe / obligate aerobe

A

An obligate aerobe is an organism that requires oxygen to grow. Through cellular respiration, these organisms use oxygen to metabolise substances, like sugars or fats, to obtain energy

86
Q

strict anaerobes

A

Obligate anaerobes are microorganisms killed by normal atmospheric concentrations of oxygen

87
Q

facultative anaerobe

A

A facultative anaerobe is an organism that makes ATP by aerobic respiration if oxygen is present, but is capable of switching to fermentation if oxygen is absent

88
Q

aerotolerant

A

Aerotolerant anaerobes use fermentation to produce ATP. They do not utilize oxygen, but they can protect themselves from reactive oxygen molecules. In contrast, obligate anaerobes can be harmed by reactive oxygen molecules.

89
Q

microaerophilic organisms

A

A microaerophile is a microorganism that requires oxygen to survive, but requires environments containing lower levels of oxygen than are present in the atmosphere.

90
Q

aerobic, facultative anaerobic, and microaerophilic bacteria all possess what 2 enzyme for energy generation

A

possess superoxide dismutase and catalase

91
Q

Aerotolerant anaerobes such as streptococci possess what 2 enzymes for energy generation ?

A

Aerotolerant anaerobes such as streptococci possess superoxide dismutase and peroxidase instead of catalase.

92
Q

Do have aerotolerant anaerobes have catalase?

A

They are catalase negative and

carry out a fermentative metabolism even in the presence of oxygen.

93
Q

T/F Strict anaerobes lack superoxide dismutase and catalase

A

True! Strict anaerobes lack superoxide dismutase and catalase and therefore cannot utilize oxygen which is deadly for them.

94
Q

Strict anaerobes carry out what 2 forms of energy production ?

A

They carry out fermentation and anaerobic respiration. Strict anaerobes lack superoxide dismutase and catalase and therefore cannot utilize oxygen which is deadly for them.

95
Q

What is a Siderophore?

A

a molecule which binds and transports iron into microorganisms.

96
Q

What are hemophores

A

a molecule which binds and transports heme io microorganisms.

97
Q
  • An increase in cell number.
A

bacterial cell growth

98
Q

What are the 4 phases of bacterial growth?

A
  1. lag phase
  2. exponential growth phase
  3. stationary phase
  4. phase of decline
99
Q

Does cell division occur during lag

A

no!

100
Q

Name 2 characteristics about lag phase

A

There is no cell division during lag phase (variable length) but there is a marked increase in metabolic activity

101
Q

There is no cell division during ____ phase but there is a marked increase in metabolic activity.

A

Lag

102
Q

you got this

A

:)

103
Q

cells are in a state of balanced growth; ratio of RNA
and DNA is proportional to growth rate; cell number doubles with each generation; cells are dividing at a
constant rate. What bacterial growth phase is this ?

A

Exponential phase

104
Q

____ phase is characterized by decreased growth rate, accumulation of
waste products, and exhaustion of nutrients.

A

stationary phase

105
Q

_____ phase is characterized by cell death.

A

phase of decline

106
Q

T/F generation time is the time it takes for 1 cell to divide into 2 cells

A

True

107
Q

What are 4 ways that bacteria transport things into the cell

A
  1. diffusion (water)
  2. facilitated diffusion (glycerol)
  3. active transport (amino acids, lactose)
  4. group translocation system or PTS (phosphotransferase system).
108
Q

glycerol is able to enter the cell through which method?

A

Facilitated diffusion

109
Q

is ATP required for facilitated diffusion?

A

No ! It requires a membrane carrier protein but has no energy requirement; molecules
move down a concentration gradient.

110
Q

T/F active transport requires an energy source

A

True! Active transport requires a membrane carrier protein and energy source.

111
Q

Describe binding protein dependent (shock-

sensitive) active transport

A
  1. requires :
    a) membrane carrier protein
    b) binding protein
    c) ATP
  2. shocking cells can reduce the efficiency of this
    kind of transport in gram-negatives;
112
Q

Describe ion dependent (shock insensitive) active transport

A

Requires:
A) a membrane carrier protein
B) energy in the form of PMF

113
Q

The transport of lactose is an example of ion depended or binding protein dependent shock sensitive active transport?

A

ion dependent (shock insensitive) active transport

114
Q

The transport of galactose and maltose is an example of ion depended or binding protein dependent shock sensitive active transport?

A

binding protein dependent (shock-sensitive) active transport

115
Q

How does active transport differ from other mechanisms of transport?

A

Active transport differs from other mechanisms of transport in that molecules are moved
against a concentration gradient, taking substances from areas of low concentration to areas of high
concentration.

116
Q

killing of all forms of life including spores is called

A

Sterilization

117
Q

What sterilization

A

The killing of all forms of life including spores

118
Q

killing of vegetative cells is called

A

disinfection

119
Q

How does disinfection differ from sterilization ?

A

sterilization kills spores, disinfection does not

120
Q

2 sporulating organisms of medical significance

are

A

Bacillus and Clostridium

121
Q

look up why Bacillus and Clostridium are of medical significance

A

idk

122
Q

T/F killing is exponential

A

True! not all organisms die at once.

123
Q

Do all organisms die at once during kiling

A

no!

124
Q

What is the most effective method of sterilization ?

A

Most effective method of sterilization is by autoclaving

125
Q

List the requirements for proper autoclaving in terms of
temp-
pressure-
time-

A

121oC
15 lbs. pressure
15-20 minutes

126
Q

how long does dry heat sterlizaiton take ?

A

2 hours

127
Q

When using dry heat sterilization what temp do you use

A

160 celcius

128
Q

T/F boiling is a form of sterilization

A

FALSE! Boiling is not sterilization; does not kill spores.

129
Q

Formaldehyde is an alkylating agent and targets ______groups on proteins.

A

Formaldehyde is an alkylating agent and targets functional groups on proteins, i.e., COOH, SH, OH groups.

130
Q

________ is alkylating agent more effective than ______ as a sporicidal agent

A

Glutaraldehyde, Formaldehyde

131
Q

Sterilization of heat-sensitive materials involves use of ______ which is an alkylating agent that
targets the DNA and protein.

A

Sterilization of heat-sensitive materials involves use of ethylene oxide which is an alkylating agent that
targets the DNA and protein.

132
Q

ethylene oxide can be used to sterilize what kind of materials?

A

Heat sensitive materials

133
Q

If i have a heat-sensitive liquid i.e. protein, drugs, etc. what can I use to sterilize it ?

A

Filtration – is used to sterilize heat-sensitive liquids, i.e. protein, drugs, etc.

134
Q

Effectiveness of sterilization in an autoclave is determined using what ?

A

Effectiveness of sterilization in an autoclave is determined using spore test strips from Bacillus stearothermophilus.

135
Q

What mechanism of killing by disinfection is described

Disrupt membrane resulting in cell lysis.

A

detergents - disrupt membrane resulting in cell lysis

136
Q

What mechanism of killing by disinfection is described:

Oxidizing agents, oxidizing proteins, lipids, carbohydrates – (sporicidal at high concentrations)

A

halogens – oxidizing agents, oxidizing proteins, lipids, carbohydrates – (sporicidal at high concentrations)

137
Q

What mechanism of killing by disinfection is described:

cause denaturation of protein and disorganize lipids; heat – denaturation of macromolecules

A

alcohols - cause denaturation of protein and disorganize lipids; heat – denaturation of macromolecules

138
Q

What mechanism of killing by disinfection is described:

Causes pyrimidine formation in the DNA which inhibits DNA replication

A

ultraviolet light - causes pyrimidine formation in the DNA which inhibits DNA replication

139
Q

What mechanism of killing by disinfection is described:

Targets the cell membrane resulting in lysis and protein denaturation

A

phenol - targets the cell membrane resulting in lysis and protein denaturation

140
Q

What mechanism of killing by disinfection is described:

Form mercaptides with sulfhydryl groups of cysteine in proteins

A

heavy metals (mercury, silver, arsenic) – form mercaptides with sulfhydryl groups of cysteine in proteins.

141
Q

What mechanism of killing by disinfection is described:

Causes single strand breaks in the DNA

A

ionizing radiation - causes single strand breaks in the DNA