Lecture 6 Flashcards Preview

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Flashcards in Lecture 6 Deck (110):
1

Is the cell wall living or non living?

non living

2

is the cell wall extracellular?

no

3

Is the cell wall an integral part of the cell

yes

4

is the cell wall the same thing as the glycocalyx?

no

5

how much of the dry weight of a cell is its cell wall?

20-40%

6

what is plasmoptysis?

bursting of the cell
osmotic lysis

7

what are the general properties of the cell wall?

non living
not extra cellular
is 20-40% of the dry weight of the bacteria

8

What sort of osmotic conditions do bacteria live in?

low osmotic conditions

9

Does water flow into or out of the cell?

into the cell

10

Use the terms hypertonic, isotonic, and/or hyoptonic to describe a cell and its ideal environment

The cell is slightly hypertonic to its environment
the environment is slightly hypotonic to the cell

11

you have 2 samples. sample A is hypertonic to sample b
which has a lower solute concentration?

sample b does

12

does the cell wall shrink during plasmolysis?

no

13

does the cell membrane shrink during plasmolysis?

yes

14

What shape would bacteria be without a cell wall?

spheres

15

what are the functions of the cell wall?

prevents plasmoptysis
gives shape
provides an anchor for flagella
acts as a sieve

16

what is a sieve?

a filter, semipermiable membrane

17

does the cell wall allow things to pass through it?

yes but it is selective and won't let everything through

18

what is murein?

a peptido glycan
the backbone of the cell wall

19

What does NAM stand for?

N-acetylmuramic acid

20

What does NAG stand for?

N-acetylglucosamine

21

Is NAM found in all organisms?

only bacteria

22

Is NAG found in all organisms?

yes

23

How are NAM and NAG attached?

covalent bonds

24

What is attached by peptide inter-bridges?

NAMs

25

Name three magic bullets

Pennicillin
Cephalosporins
Lysozomes

26

What is a principle component of chiton?

NAG

27

How are NAM molecules connected?

peptide inter bridges

28

How do cephalosporins work?

targets the murien in the cell walls by breaking the peptide inter-bridges which ultimately destroys the cell wall

29

What color is a G+ organism after staining and counter staining?

purple

30

What color is a G- organism after staining and counter staining?

pink

31

What is the most supported theory as to why G+ and G- bacteria are different?

a permeation phenomenon based on the cell wall thickness

32

Do G+ or G- bacteria have teichoic acid?

G+

33

Do G+ or G- bacteria have O-polysaccharied?

G-

34

Do G+ or G- bacteria have lysine?

G+

35

Do G+ or G- bacteria have Diaminopimelic acid?

G-

36

Do G+ or G- bacteria have an outer 2nd membrane?

G-

37

Do G+ or G- bacteria have porins?

G-

38

Do G+ or G- bacteria have more murien in their wall?

G+ has more

39

what percent murein is a G+ cell wall?

50-90%

40

what percent murein is a G- cell wall?

10-20%

41

Do G+ or G- bacteria have a thicker layer of murein in their wall?

G+ has a thicker layer

42

What thickness of murein does a G- bacteria have?

10nm

43

What thickness of its murein layer does G+ have?

20-80nm

44

Do yeast stain G+ or G-?

G+

45

Do fungi have chitin?

yes

46

Do fungi have murein?

no

47

Do all bacteria have an outer membrane?

no, only G- have an outer membrane

48

What is the outer membrane made of?

lipopolysaccharides (LPS)

49

What happens when G- bacteria die?

their outer membrane breaks down into an endotoxin

50

What happens during gram negative shock?

you go into shock, your blood pressure drops and you get a fever

51

Does the outer membrane let everything into the cell?

no, it is selectively permiable

52

What does the outer membrane use to let things through it?

porins

53

What does the outer membrane protect against?

antibiotics
detergents
bile

54

What does bile do?

it emulsifies lipids

55

How does Smith describe the peptidoglycan layer's position in the cell?

"It is between the cell membrane and the outer membrane"

56

Where in the cell is the periplasmic space?

it is between the outer most wall/membrane and the innermost membrane, it may be divided up into pieces if the peptidoglycan layer is present

57

What does the alcohol do to G- bacteria when gram staining?

it poles holes in the outer membrane

58

What is the first living part of the cell?

the cell membrane

59

What is the living part of the cell called?

the protoplast

60

Is the cell membrane impermeable, selectively permeable, or differentially permeable?

differentially permeable

61

What is the protoplast?

the living part of the cell

62

What does differentially permeable mean?

it regulates what is transferred through the cell, not just based on size like selectively permeable

63

Do bacteria have cholesterol in their cell membrane?

no

64

what makes up the bacteria's cell wall?

enzymes

65

What are the purposes of the bacterial cell membrane?

Respiration and regulation

66

What is the chemical make up of a phospholipid?

1 glycerol
2 fatty acids
1 phosphate
1 organic group

67

What is the chemical make up of glycerol?

a 3 carbon alcohol, 3 alcohol groups

68

At what carbon is the phosphate group

it is at the third carbon

69

What is the fluid mosaic model?

the phospholipid molecules and the proteins in the membrane can move

70

what does amphipathic mean?

a molecule which has both hydrophobic and hydrophilic regions

71

Do bacteria have cholesterol or ergosterol?

no

72

In what organisms can you find ergosterol?

fungi

73

In what organisms can you find cholesterol?

animals

74

Is a phospholipid amphipathic?

yes

75

Which part of the phopholipid is hydrophillic?

the phosphate head

76

Which part of the phospholipid is hydrophobic?

the lipid tail

77

What is a sterol?

a steroid linked to an alcohol group

78

Do bacteria have a nucleus?

no

79

Do bacteria have a nucleoid?

yes

80

how many chromosomes do bacteria have?

1

81

What are plasmids?

additional DNA that are sometimes found in bacteria

82

Do bacteria have extrachromosomal DNA?

yes, plasmids

83

Do humans have extrachromosomal DNA?

yes, in our rhibosomes

84

what do plasmids generally code for?

drug resistance

85

What is the organelle of locomotion?

the flagella

86

Does the flagella affect virulence? how so?

yes, it makes it easier for them to invade the body

87

What is the main way that organisms become drug resistant?

plasmids

88

What stain do you use to stain for flagella?

silver stain

89

Describe a bacterial flagella

a single microfillament that rotates to move and is very long

90

Describe a eukaryotic flagella

In eukaryotes fillaments are in a 9+2 arrangement (9 pairs on the outside, 2 in the center of the microtubules)

91

Which are longer flagella or fimbriae?

flagella

92

What is the purpose of fimbriae?

used for attachment to the host cell

93

Name two organisms which have fimbriae?

Nesseria gonorrhea
e. coli

94

What is opthalmia neonaterum?

newborns are blinded by passing through their mother's gonorrhea infested vagina during birth

95

How are fimbriae and virulence related?

Organisms that lack fimbriae are less pathogenic

96

What is the plural of pulus?

pili

97

What is conjugation?

sharing/exchange of DNA from the nucleoid or the plasmids using a pilus

98

does conjugation lead to genetic recombination?

yes

99

What does the pilus do?

it attaches conjugating bacteria

100

What causes q fever?

coxiella brybati

101

What do endospores do?

they allow for a species to outlive harsh conditions

102

Are endospores a form of reproduction?

no

103

what is the endospore formed in?

it is formed inside the vegetative cell

104

What is the difference between sterilization and disinfection?

Disinfection kills everything but endospores
Sterilization kills endospores as well as everything else

105

name 4 organisms that form endospores

bacillus
clostridium
sporosarcinae
coxiella brybati

106

what shape is sporosarcinae?

cocci

107

what disease does sporosarcinae cause?

it causes no disease

108

where is coxiella brybati found?

unpasturized milk

109

What diseases have endospores?

anthrax
tetnus
q-fever

110

how many endospores are there formed per cell?

1