Brainscape's Knowledge GenomeTM

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


See full index

BIOL 2330 - microbiology > functional anatomy of the prokaryotic cell > Flashcards

functional anatomy of the prokaryotic cell Flashcards

You may prefer our related Brainscape-certified flashcards:
Biology 101 flashcards
1
Q

what is the cell envelope

A

the plasma membrane and all layers external to it

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

what does glycocalyx mean

A

sugar coat

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

where is the glycocalyx

A

part of the cell envelope, exterior to the cell wall

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

what is the glycocalyx in terms of composition

A

a network of polysaccharides

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

what are the two types of glycocalyx

A

capsules and slime layers

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

when is the glycocalyx considered a capsule

A

when it is well organized and not easily washed off

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

when is the glycocalyx considered a slime layer

A

when it’s unorganized and loosely attached to the cell wall

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

what part of the cell is the glycocalyx attached to

A

the cell wall

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

where is the glycocalyx made

A

inside the cell

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

from being made inside the cell, how does the glycocalyx get outside of the cell

A

it’s secreted to the surface

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

T or F: all bacteria have a glycocalyx

A

false; not all of them do

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

T or F: for the bacteria that have a glycocalyx, the chemical structure is the same across species

A

false; the chemical structure will vary across species

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

describe the advantages of having a glycocalyx

A

they help bacteria resist phagocytosis b/c they’re slippery, they aid in attachment to surfaces, prevent desiccation b/c the layer contains lots of water, they inhibit entry to bacterial viruses or other hydrophobic toxic materials

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

what is the S layer

A

another layer of the envelope that may be present

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

what is the S layer attached to

A

the outermost portion of the cell wall

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

what does S stand for in S layer

A

surface

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

what is the S layer made up of

A

protein or glycoprotein

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

what are the functions of the S layer

A

protection against predacious bacteria/ion and pH fluctuations, or osmotic stress. Promotes adhesion to surfaces, helps maintain shape and rigidity, protects some pathogens against host defenses

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

T or F: bacteria can have both a glycocalyx and the S layer

A

true

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

T or F: all bacteria have a cell wall

A

true; except for a few instances

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

what are the major functions of the cell wall

A

protection against osmotic lysis, provides shape, protects against entry of toxic materials

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

is the cell wall external or internal to the glycocalyx and S layer

A

internal

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

what is the cell wall made up of

A

peptidoglycan

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

T or F: peptidoglycan is a polymer

A

true

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

how many subunits does peptidoglycan have

A

2

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

what type of subunits does peptidoglycan have

A

monomer subunits

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

what are the two monomer subunits of peptidoglycan

A

N-acetylglucosamine and N-acetylmuramic acid

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

how do the NAM and NAG arrange themselves in peptidoglycan

A

they form a backbone of 10-65 rows

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

are NAM and NAG the only components of the peptidoglycan backbone?

A

no, there are also tetrapeptides (peptide made up of 4 amino acids)

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

what are tetrapeptides

A

peptides made up of 4 amino acids

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

what do the tetrapeptides do in the peptidoglycan backbone

A

they crosslink strands of the backbone together

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

what is the shape of the NAM-NAG strands in peptidoglycan

A

helical

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

T or F: tetrapeptides can attach to both NAM and NAG

A

false; they only attach to NAM

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

which do tetrapeptides attach to: NAM or NAG?

A

NAM only

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

name the two ways in which crosslinking of the peptidoglycan can occur

A

direct linkage

peptide interbridge

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

describe direct linkage of the peptidoglycan backbone

A

a peptide bond is formed between the two tetrapeptides

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

describe a peptide interbridge of the peptidoglycan backbone

A

a peptide bridge attached to each tetrapeptide (ie a string of glycines will connect them)

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

which type of bacteria favors direct linkage of the peptidoglycan backbone

A

gram negative

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

which type of bacteria favors peptide interbridge of the peptidoglycan backbone

A

gram positive

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

how does penicillin affect peptidoglycan

A

it inhibits the enzymes involved in cross linking

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

which bacteria takes more of a hit from penicillin preventing crosslinking of the peptidoglycan backbone

A

gram positive

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

T or F: the amino acids in the tetrapeptide of peptidoglycan are always the same

A

false; they can vary

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

T or F: the order of amino acids in the tetrapeptide of peptidoglycan is always the same

A

false; the order can vary

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

T or F: the position of the bridge connecting tetrapeptides in peptidoglycans can vary

A

true

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

T or F: the composition of the peptide interbridge of peptidoglycan can vary

A

true

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

what types of amino acids make up the tetrapeptide

A

alternating D and L forms

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

which do humans use to make up our proteins: D or L amino acids

A

L amino acids

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

why would D amino acids be advantageous for bacteria to use to form their cell wall

A

presence of D amino acids protects against attack by most peptidases, which only recognize L isomers

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

T or F: peptidoglycan is strong

A

true; due to NAM-NAG backbone

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

T or F: peptidoglycan is flexible

A

true; due to crosslinks

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

T or F: peptidoglycan is porous

A

true

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

which domain is peptidoglycan found in

A

Domain bacteria

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

T or F: peptidoglycan can be found in organisms not belonging to Domain Bacteria

A

false; it’s only found in Domain Bacteria

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

describe the cell wall structure in a gram pos bacteria

A

a thick layer of peptidoglycan with lots of cross links

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

what are teichoic acids

A

a polymer of an alcohol (glycerol or ribitol) linked by phosphate groups

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

what type of charge do teichoic acids have

A

negative

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

where are teichoic acids located in gram pos bacteria

A

within the cell walls

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

what are the two types of teichoic acids

A

wall teichoic acids

lipoteichoic acids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

describe wall teichoic acids

A

they’re bound covalently to peptidoglycan (NAM)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

are wall teichoic acids bound to NAM or NAG

A

NAM

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

describe lipoteichoic acids

A

they’re bound to lipids that are present in the PM

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

describe the functions of teichoic acids

A

help maintain cell envelope structure, involved in binding pathogenic species to host tissues, and they protect bacteria from harmful substances

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

T or F: in gram pos bacteria, some proteins may associate with the peptidoglycan layer

A

true; they may be involved in adhesion or virulence

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
64
Q

describe the cell wall structure of a gram neg bacteria

A

a thin layer of peptidoglycan and an outer membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
65
Q

what is the outer membrane composed of

A

a phospholipid bilayer consisting of phospholipids, lipoproteins, and lipopolysaccharides

66
Q

describe the structure of a phospholipid

A

phosphate, glycerol, and two fatty acids

67
Q

what do lipoproteins do

A

link the outer membrane to the peptidoglycan in gram neg bacteria

68
Q

what is the most abundant lipoprotein in gram neg bacteria

A

Braun’s lipoprotein

69
Q

describe the basic structure of lipopolysaccharides (LPS)

A

3 parts: lipid A, core polysaccharide, and the O side chain

70
Q

how many sugars and phosphates make up the core polysaccharide in an LPS

A

10

71
Q

T or F: the O side chain is always the same in an LPS

A

false; it will differ between strains

72
Q

how does the gram neg bacteria get it’s negative charge

A

lipopolysaccharide gives it the neg charge

73
Q

what part of an LPS is embedded in the membrane

A

lipid A

74
Q

which part of an LPS is toxic

A

lipid A

75
Q

what is another name for lipid A in LPS since it’s toxic

A

Endotoxin

76
Q

describe how lipid A of LPS is toxic

A

sometimes the endotoxin can be released into the blood and cause shock when you have a bacterial infection

77
Q

functions of LPS in gram neg bacteria?

A

stabilizes outer membrane via lipid A, protects the cell by acting as a permeability layer, protects pathogenic species from host defenses (bacteria will change the makeup of O so the host antibodies don’t work)

78
Q

how many membranes do gram neg bacteria have

A

2

79
Q

what additional membrane does a gram neg have

A

an outer membrane

80
Q

what is embedded in the outer membrane of gram neg bacteria

A

porins

81
Q

what are porins

A

they form a channel that spans the outer membrane and allows small molecules to pass through

82
Q

how can peptidoglycan be destroyed

A

by penicillin or lysozyme

83
Q

describe how penicillin and lysozyme can break down peptidoglycan

A

lysozyme breaks NAM-NAG bonds = osmotic lysis

penicillin and lysozyme cause bacteria to lyse in a hypotonic environment

84
Q

describe peptidoglycan in a hypotonic environment with penicillin and lysozyme

A

lysozyme digests wall (breaks NAM-NAG bonds), water enters, lysis happens

85
Q

will a bacteria lyse in an isotonic environment?

A

no

86
Q

describe a gram pos bacteria in an isotonic environment and why it will not lyse

A

when treated with penicillin and lysozyme, the cell wall will be lost and the cell becomes a protoplast and remains intact

87
Q

what is a protoplast

A

a gram pos organism that has lost its cell wall

88
Q

describe a gram neg bacteria in an isotonic environment

A

peptidoglycan layer is lost but the outer membrane remains = spheroplast

89
Q

what is a spheroplast

A

gram neg bacteria that have lost the peptidoglycan layer but still contain the outer membrane

90
Q

which bacteria are more sensitive to penicillin and lysozyme + why

A

gram pos because they don’t have that protective outer membrane

91
Q

describe the gram stain: addition of primary stain

A

crystal violet enters the cytoplasm and colours both groups of bacteria purple

92
Q

describe the gram stain: addition of iodine

A

iodine acts as a mordant and forms large crystals with the stain. this now becomes too large to escape through the cell wall

93
Q

describe the gram stain: decolorizer

A

gram pos: alcohol dehydrates the peptidoglycan layer so it’s impermeable to the iodine-CV complex = purple is trapped

gram neg: alcohol dissolves lipids of outer membrane, iodine-CV complex can escape = purple leaves

94
Q

describe the gram stain: addition of counterstain

A

safranin is added so gram negative organisms will stain red, gram positive will remain purple

95
Q

T or F: some gram pos organisms can give a gram neg response (in regards to gram stain)

A

true

96
Q

when will gram pos organisms give a gram neg repsonce in regards to a gram stain

A

when the cells are dead

97
Q

describe what it means to be gram variable

A

as the culture ages, more and more cells will look gram negative

98
Q

describe how members of the Genus Mycoplasma have an atypical cell wall

A

no cell wall and are only surrounded by a PM. To protect against lysis, many have cholesterol in the PM

99
Q

describe how members of Phylum Chlamydiae and Phylum Plantomycetes have atypical cell walls

A

they have a cell wall that contains only an outer membrane (no layer of peptidoglycan)

100
Q

what is the periplasmic space

A

region between the cell wall and the PM

101
Q

which type of bacteria (gram pos or neg) has a large volume

A

gram neg has a large periplasmic space

102
Q

what is the name for the substance occupying the periplasmic space

A

the periplasm

103
Q

what does the periplasm contain inside of it

A

various types of proteins

104
Q

describe the protein types located in the periplasm

A

hydrolytic enzymes, transport proteins, proteins involved in making peptidoglycan, proteins involved in detoxifying harmful compounds

105
Q

T or F: bacterial plasma membranes contain sterols

A

false; they do not contain sterols like animal membranes do

106
Q

instead of sterols, what do bacterial PMs have

A

sterol-like molecules called hopanoids

107
Q

define hopanoid

A

a sterol-like molecule that is located in a bacterial PM

108
Q

function of a hopanoid?

A

help stabilize the membrane

109
Q

what two types of proteins does the PM contain

A

peripheral and integral

110
Q

what do peripheral proteins do

A

act as enzymes and provide support for the membrane

111
Q

what do integral proteins do

A

they transport materials and are involved in energy conservation

112
Q

list some functions of the PM

A

selectively permeable, site of cell resp (ETC), site of photosynthesis (photosystems), site of lipid synthesis and cell wall components, contains receptor molecules

113
Q

what major structures are located in the cytoplasm

A

nucleoid, ribosomes, and inclusions

114
Q

what are the three cytoskeletal elements in EUKARYOTES

A

microfilaments, microtubules, intermediate filaments

115
Q

describe the BACTERIAL cytoskeleton

A

contains homologues of all three types of eukaryotic proteins (MTs, MFs, IFs) + they contain unique proteins that aren’t in eukaryotes

116
Q

what are the functions of the unique proteins found in the bacterial cytoskeleton

A

aid in cell division, help localize proteins to specific sites within the cell, they help determine cell shape

117
Q

what is a nucleoid

A

irregularly shaped region where the DNA is found

118
Q

T or F: the nucleoid has a membrane

A

false; it has no membrane, so it’s only a region of the cell

119
Q

describe the structure of prokaryotic DNA

A

a single, double-stranded, helical, circular DNA molecule

120
Q

what is the single, double-stranded, helical, circular DNA molecule called in bacteria

A

bacterial chromosome

121
Q

what proteins are in the nucleoid that aid in packaging DNA

A

nucleoid associated proteins (NAPS) (ie the HU protein)

122
Q

what are plasmids

A

extrachromosomal DNA

123
Q

where are plasmids located

A

in the cytoplasm

124
Q

T or F: plasmids exist independently of the bacterial chromosome

A

true

125
Q

what shapes can a plasmid be

A

linear or circular

126
Q

T or F: plasmids are required for survival

A

false; but they can give a specific advantage

127
Q

ribosomes are the site of __ ___

A

protein synthesis

128
Q

where in the cell are ribosomes located

A

within the cytoplasm or loosely attached to the PM

129
Q

what are ribosomes in prokaryotes denoted as

A

70S

130
Q

what does S stand for in 70S

A

Svedberg unit

131
Q

what is a svedberg unit

A

a unit of measurement that measures the relative rate of sedimentation during ultra-high speed centrifugation. It’s a function of the size, weight, and shape of the subunits

132
Q

describe what makes up the 70S ribosome

A

30S subunit and the 50S subunit

133
Q

what are ribosomes made up of (hint: what molecules)

A

rRNA and protein

134
Q

T or F: some organisms in Bacteria and Archaea have internal membranous structures

A

true

135
Q

describe the intracytoplasmic membranes of cyanobacteria

A

they carry out photosynthetic reactions, so they have internal membranes called thylakoids

136
Q

other than cyanobacteria, which organism has intracytoplasmic membranes

A

nitrifying bacteria (soil organisms that convert nitrogen compounds into forms usable by green plants)

137
Q

what is the main function of intracytoplasmic membranes

A

increase surface area to carry out metabolic activities

138
Q

what are inclusions

A

aggregates of organic or inorganic substances

139
Q

where are inclusions located

A

cytoplasm

140
Q

what form can inclusions be

A

granules, crystals, globules

141
Q

T or F: inclusions are visible with the light microscope

A

true

142
Q

describe membranes of inclusions

A

inclusions can be membrane-bound or free in the cytoplasm

143
Q

T or F: some inclusions may be found in invaginations of the PM

A

true

144
Q

what are 3 types of storage inclusions

A

carbonosome, polyphosphate granule, sulfur globule

145
Q

what do carbonosomes do

A

store carbon

146
Q

what do the most common type of carbonosomes contain

A

PHB

147
Q

what do polyphosphate granules do

A

store phosphate

148
Q

what do sulfur globules do

A

store sulfur

149
Q

what are magnetosomes

A

inclusions of iron oxide

150
Q

structure of magnetosomes

A

linear

151
Q

location of magnetosomes

A

underneath the PM, found in aquatic bacteria

152
Q

function of magnetosomes

A

allow bacteria to orient themselves with respect to the earth’s magnetic field (ie know which way is up)

153
Q

T or F: a gas vacuole is surrounded by a membrane

A

false; it has no membrane

154
Q

which bacteria have gas vacuoles

A

aquatic bacteria (that are generally photosynthetic)

155
Q

how is a gas vacuole formed

A

formed from many small, hollow, cylindrical structures called gas vesicles

156
Q

T or F: gas vacuoles are impermeable to water

A

true

157
Q

T or F: gas vacuoles are impermeable to atmospheric gases

A

false; they are freely permeable to atmospheric gases

158
Q

function of gas vacuoles?

A

they allow bacteria to regulate their buoyancy so they can get optimal light, oxygen, and nutrients

159
Q

what are microcompartments (ie structure, orientation)

A

large polyhedrons made up of a protein shell. They encompass enzymes

160
Q

example of a microcompartment?

A

carboxysome

161
Q

which organisms are carboxysomes found in

A

cyanobacteria

162
Q

function of carboxysomes in cyanobacteria?

A

contain the enzymes required for CO2 fixation (ie the dark phase of photosynthesis)

BIOL 2330 - microbiology (30 decks)

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