Brainscape's Knowledge GenomeTM

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


See full index

CELS 191 > Microbiology > Flashcards

Microbiology Flashcards

1
Q

Draw a prokaryotic cell

A

Lecture 1

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

What are the 3 shapes of bacteria?

A

Cocci
Rods
Spirals

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

What is an important feature in eukaryotic cells not found in prokaryotic cells?

A

Nuclear envelope

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

What shape is a bacteria chromosome?

A

Singular, circular

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

Where is the chromosome of a bacteria found?

A

Nucleoid

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

What are plasmids?

A

Small, self-replicating DNA molecules found in the cytosol

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

What is a bacteria cell wall made out of?

A

Peptidoglycan

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

What is the purpose of a cell wall

A

Stops the cell from bursting.
Confers cell shape
Provides strength to the cell

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

What is the structure of peptidoglycan?

A

Alternating units of NAG and NAM
For structure, they are linked together with amino acids.

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

What is transpeptidase?

A

Enzyme that cross-links the peptidoglycan chains to form rigid cell walls

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

What cells are dyed purple by the crystal violet and why?

A

Gram positive because they have a thick cell wall

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

Which cells are dyed using the counter stain? And why?

A

Gram-negative because they have a thinner layer of peptidoglycan so doe not hold crystal violet very well

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

How are bacteria capable to moving?

A

Using flagella

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

Ho big are flagella?

A

5-20nm

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

What is chemotaxis?

A

Bacteria moving along a concentration gradient towards a chemical gradeint

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

What is a fimbriae?

A

Structures with adhesive structures on the surfaces of cells

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

Are fimbriae more or less numerous than flagella?

A

More

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

What is a pili?

A

Adherent factor on bacteria that allows them to attach to other bacteria and transfer genetic material to each other

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

What are the 2 types of bacterial adhesive factors?

A

Pili and Fimbriae

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

What is a genetic transfer called?

A

Conjunction

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

What is glycocalyx?

A

Gelatinous polysaccharide/ peptide outer covering which forms a meshwork of fibres

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

What are the two types of glycocalyx?

A

Capsule and slime layer

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

Is a capsule or a slime layer disorganised?

A

Slime layer

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

What is the function of a capsule?

A

Virulence factors (protects from phagocytosis)
Prevents cell from drying up

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

What is a bacterial endopore?

A

Bacterial spore inside of bacteria

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

WHy do bacterial endospore form?

A

When there are unfavourable growth conditions so that they can germinate in favourable conditions.

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

What are the stressors that tirgger endospore formation?

A

Nutrient starvation
High cell density

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

Are bacterial endospores present in gram - or + bacteria?

A

Positive

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

What is binary fission?

A

Asexual reproduction for prokaryotes

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

What is the result of binary fission?

A

2 genetically identical cells

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

How are microorganisms studied?

A

Thy are cultured

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

What is a closed batch culture system?

A

A form of cell culturing where microorganisms are put in a closed system with limited amounts of nutrients

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

What are the 4 stages of microbial growth?

A

Lag, exponential, stationary, and death

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

What happens in the stationary phase of microbial growth?

A

Cells stop growing and cryptic growth is observed.

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

What happens in the lag phase of microbial growth?

A

Time required to get biosynthetic reactions running

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

What happens during the exponential phase of microbial growth?

A

Cells divide and population is growing exponentially

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

What is a determining factor of the length of the lag phase?

A

History of the inoculum

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

What is cryptic growth?

A

Dynamic population where organisms survive by consuming other dead cells within the culture

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

What is the death phase of microbial growth?

A

Equilibrium between growing and dying cells is skewed towards death

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

What are the 3 things required by prokaryotes to multiply?

A

Carbon source
Energy source
Reducing power

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

what is reducing power for prokayotes?

A

Carriers of energy/electrons

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

How do prokaryotes harvest energy?

A

Breaking chemical bonds releases energy which can be captured as ATP.

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

Describe the breakdown and buildup of energy transformation in prokaryotes

A

Lecture 2

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

What is an auxotroph?

A

An organism that is unable to synthesise one or more essential growth factors

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

What is a wildtype strain in terms of culture?

A

Can grow by itseld and has all essential genes

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

What is cross-feeding/Syntrophy?

A

When one species gain metabolic produces of another species

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

What allows for the survival of auxotrophs?

A

Cross-feeding.

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

What is a microbiome?

A

A complete collection of micro-organims and their genes in a specific environment

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

What is microbiotia?

A

Individual microbial species in a biome

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

What is a culture dependent method?

A

Reliance of culturing microbes in labs

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

What is a culture independent method?

A

Relies on nucleic acid based methods.
Sequencing of metabolic profiles to study all microbes in a sample.

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

What are the pros of culture-dependent methods?

A

Allows access to the phenotype
Can study more than 1 organism
Can manipulate the conditions

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

What are the cons of culture-dependent methods?

A

Not all organisms can be cultured
Culturing requires precise conditions
Does not match real world contions

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

What are the pros of culture-independent methods?

A

Allows access to a genotype
Can study many organisms
Shows communities as in nature

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

What are the cons of culture-independent methods?

A

not easy to manipulate
Expensive and complex

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

Is the cultured or uncultured microbial world greater?

A

Uncultured

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

What is a population in terms of microbes?

A

Individual microbial cells of a species

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

What are interactions between populations called?

A

Communities

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

What is the basis of energy transfer in cells?

A

RedOx

60
Q

How is the redox reaction shuttled?

A

Through NADH/NADPH

61
Q

What are the 4 key trophic groups in microorganisms?

A

Chemoautotrophs
Chemoheterotrophs
Photoautotrophs
Photoheterotrophs

62
Q

What does a photoautotroph do in terms of energy source and carbon source?

A

Energy source from light
Makes its own carbon

63
Q

What does a heterotroph do in terms of carbon source?

A

Decomposes/ takes carbon form other sources

64
Q

How do photo microbes avoid competition?

A

Tuning their antennae to a different wavelength

65
Q

What was the aim of the human microbiome project?

A

Characterise microbrial communities in multiple human body sites

66
Q

What were the emphasis of the human microbiome?

A

Oral, skin, vaginal, gut, nasal, and lung

67
Q

How many microbial species are in the human microbiome?

A

10,000

68
Q

How many bacteria species are in the gut?

A

500-1,000

69
Q

True or false, the gut bacteria have 50x more genetic diversity than the human genome?

A

True

70
Q

What are the main 9 things that our microbiome does for us?

A

Prevents pathogens
Blocks colonisation niches
Competing for nutrients
Modifies environment for virulence factor
Makes environment hostile
Lowers pH
Thickens mucus layer
Upregulate antimicrobial peptides
Primes neutrophils and macrophages

71
Q

What are the 4 dominant bacterial and archaeal groups in our gut microbiome?

A

Firmicutes
Bacteroidetes
Actinobacteria
Proteobacteria

72
Q

What is a function of the gut microbiome in terms of plants

A

Gut microbiota can create SCFAs that modulate our metabolisms and can break down cell walls, allowing us to digest plant matter.

73
Q

What is a function of the gut in terms of vitamins?

A

The gut can synthesise vitamens and modulate immune response

74
Q

What is a functional food?

A

Food claiming to have a health-promoting property

75
Q

What is a Probiotic?

A

Live micro-organisms that survive transit through the stomach and may help the gut

76
Q

What is a Prebiotic?

A

An ingredient that nourishes good bacteria in the large bowel or colon

77
Q

What is the purpose of a prebiotic?

A

Stimulate the growth of probiotics

78
Q

What is the difference between C. difficile and lactobacillus?

A

Nothing besides the speed of growth and the presence of accessory genes

79
Q

What is an FMT?

A

Fecal microbiota transplant which successfully treats CDI (clostridium difficile infection)

80
Q

What are viruses?

A

Genetically diverse parasitic entities that hijack the molecular resources of the host.

81
Q

What do viruses rely on to multiply?

A

Biosynthetic machinery of infected cells

82
Q

What is the composition of a virus (3)

A

Genetic material
Capsid
Envelope of lipids

83
Q

What is the capsid of a virus?

A

Protein coat that protects the genetic material

84
Q

What is the purpose of an envelope of lipids on a virus?

A

Surround the protein coat when they are outside of a cell

85
Q

What is a capsid made out of?

A

Capsomers

86
Q

How can capsids be arranged?

A

Helical
Icosahedral
Complex

87
Q

Describe the structure of a helical capsid

A

Capsomers packed tightly together with a twist so that they eventually form a helix. They can rod-like structures

88
Q

Describe the structure of a icosahedral capsid

A

Lots of axis of symmetry, made up of lots of triangles

89
Q

What shapes could a viral genome be?

A

Linear
Circular
Segmented

90
Q

What are the 4 possible forms of RNA and DNA?

A

ssRNA
dsRNA
ssDNA
dsDNA

91
Q

What do viruses infect?

A

Cells and all forms of life.
Host cells and host organisms

92
Q

What is a bacteriophage?

A

Viruses that infect and replicate in bacteria

93
Q

What is the lytic cyles of a bacteriophage infection? (6)

A
  1. Attach
  2. Penetrate
  3. Uncoat
  4. Genome replication
  5. Assembly
  6. Release
94
Q

What is the result of bacteriophage infection?

A

Many copies of the virus

95
Q

What is the result of viral RNA polymerase copying a gene?

A

Errors, this allows tracking and leads to new strains.

96
Q

What is the purpose of a spike in a virus?

A

Attachment and cell entry, major target for neutralising immunity

97
Q

What are the 3 properties of a bacterial genome?

A

Single, circular
No nuclear membrane
Other DNA molecules can be found known as plasmids.

98
Q

What is horizontal gene transfer?

A

Gene transfer directly from one organism to another

99
Q

What is vertical gene transfer?

A

From a parent to an offspring

100
Q

What are the 2 important attributes transferred horizontally by bacteria?

A

Virulence factors
Antibiotic resistance

101
Q

What is a virulence factor?

A

Things that help bacteria survive within the host e.g. smooth capsule

102
Q

What are the 3 strategies of horizontal gene transfer?

A

Transformation
Transduction
Conjugation

103
Q

Describe Transformation in terms of horizontal gene transfer

A

DNA from dying or dead bacteria and released into the environment. They then enter other bacteria

104
Q

Describe transduction in terms of horizontal gene transfer

A

Done by a bacteriophage. Tall capsules which can connect to other cell membranes and inject them with genetic material

105
Q

Describe conjugation in terms of horizontal gene transfer

A

Sex pili between beacteria allowing them to transfer plasmids (DNA)

106
Q

What is an advantage of bacteriophage therapy?

A

Specific
Occur naturally
Safe
Active against antibiotic resistant bacteria

107
Q

What is a disadvantage of bacteriophage therapy?

A

Difficult to administer
Not accessible

108
Q

What are the 4 key stages to microbial pathogenesis?

A

Adherence
Invasion
Replication
Damage to host tissues

109
Q

What are the toxic virulence factors?

A

Endotoxins
Exotoxin

110
Q

What are the 3 types of exotoxins?

A

Cytotoxins
Neurotoxins
Enterotoxins

111
Q

What affect does a cytotoxin have?

A

Complete lysis of red blood cells

112
Q

What affect does a neurotoxin have?

A

Paralysis

113
Q

What affect does a enterotoxin have?

A

Severe dystentry

114
Q

What is an exotoxin?

A

Proteins produced within living bacteria, then released into the surrounding medium

115
Q

What is selective toxicity?

A

Bacteria taking up different things (selectively), so that medicine can kill viruses and not host cells

116
Q

How discovered Penicillin?

A

Alexander Fleming

117
Q

How does Penicillin work?

A

By interfering with the formation of a bacterial cell wall (the peptidoglycan cross bridges)

118
Q

Describe the concept of antibiotic resistance

A

Proportion of bacteria with a mutant survive and go on to multiply, forming a resistant colony.

119
Q

What is beta lactamase?

A

Enzyme produced by bacteria to destroy penicillin

120
Q

Can antibiotic resistance be tranferred horizontally?

A

Yes

121
Q

In what 4 ways can we reduce the development of antibiotic resistance?

A

Restrict utilization (in agriculture)
Improve diagnostics (more effective treatment)
Identify new targets
Combination therapies

122
Q

What are the 5 stages of an infectious disease?

A

Incubation Period
Prodromal
Illness
Decline
Convalescence

123
Q

What is the most infectious stage?

A

Illness

124
Q

What makes Rhinoviruses easy to destroy?

A

They have a naked capsid

124
Q

Describe the chain of infection (6)

A

Causative agent
Source
Means of exit
Mode of transmission
portal of entry
Person at risk

125
Q

What is mortality?

A

Incidence of death within a population

125
Q

What is morbidity?

A

Incidence of the disease, both fatal and non-fatal cases

126
Q

What is prevalence?

A

Total number of new and existing cases in a population at a given time

126
Q

What are crude death rates talking about?

A

Mortality

126
Q

What is incidence?

A

Number of new cases of a disease over a given time

127
Q

What is an endemic disease?

A

Disease that is commonly present (baseline) in a community

128
Q

What is a sporadic disease?

A

Occurs infrequently and irregularly in that location

129
Q

What is an epidemic?

A

Increase in the number of cases in a particular area

130
Q

What is a pandemic?

A

An epidemic spread over several countries and continents

131
Q

How much of the world’s population is affected by HIV

A

0.6%

132
Q

How can HIV be treated

A

Anti-retroviral drugs

133
Q

Do viruses have genomes?

A

Yes

134
Q

What do you find when you sequence the HIV genome?

A

That bacteria have phylogenetic trees

135
Q

What explains the tree of HIV sequences?

A

Infection from multiple viruses
Viruses are changing

136
Q

What are the arguments for virus changing?

A

For: viruses within a patient are more similar than those between
Against: The same virus can be found in multiple parts of the tree

137
Q

What are the arguments for multiple viruses

A

For: Multiple sequences
Against: Viruses are more similar within patients

138
Q

What are the two types of HIV sequence changes?

A

Proximate
Ultimate

139
Q

What kind of virus is HIV?

A

Lentivirus

140
Q

What kind of genome does HIV Have?

A

RNA

141
Q

What is reverse transcription

A

When RNA is turned back into DNA with lots of errors and therefore more variants are formed

142
Q

What parts of the HIV virus makes it prone to selection?

A

Immune System
Drug regimen
Changes in the receptor
Tropism in tissues

143
Q
A

CELS 191 (4 decks)

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