Brainscape's Knowledge GenomeTM

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


See full index

CELS MCQ & Structure > Module 4 Structure > Flashcards

Module 4 Structure Flashcards

1
Q

Flagellum Function

A

Provide Motility

Acts like a propeller.

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

Cell Wall Function

A

Provides strength to the bacterial cell
Determines Bacterial cell shape
Protects against osmotic lysis.

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

Capsule Function

A

Protect cell from attack by host’s immune system (phagocytosis)
Prevents bacterial cell from desiccation (drying out)
Aids in bacteria adhering to cell surfaces & structures
Act as a source of nutrients.

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

Fimbriae Function

A

Attachment (adhesion) of bacterial cells to surfaces.

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

Draw a diagram of a microbial growth curve for a closed batch culture system.

A 
Death/decline phase
Lag phase
Log/exponential phase
Number of living bacterial cells (Log10)
Stationary phase
Time
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Which phase would a microbiologist use to calculate the fastest doubling time (growth rate) of a bacterium?

A

Log Exponential Phase

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

By which process do bacteria multiply?

A

Binary Fission

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

In what phases are the cells most likely to be sensitive to penicillin?

A

Log Exponential Phase

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

Why are cells sensitive to penicillin in this phase?

A

Cells are replicating/growing/dividing/ during this phase,

Cell wall being synthesised/turned over.

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

why is a ‘persister’ bacterium insensitive to penicillin treatment?

A

In a Dormant, non-dividing phase.
Penicillin targets bacteria as they are growing/dividing (and
synthesising cell wall), bacteria that are in this dormant, non-dividing phase are not targeted by penicillin.

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

What are the 3 main things microorganisms need in order to grow?

A
  1. Carbon source (building blocks for macromolecular synthesis)
  2. Energy source (energy (electrons) to drive anabolic and catabolic reactions in the cell)
  3. Reducing power (carriers of energy/electrons (NAD+
    /NADP+)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Carbon source

A

Building blocks for macromolecular synthesis

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

What is Carbon source?

A

Building blocks for macromolecular synthesis

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

What is Energy source?

A

Energy electrons to drive anabolic and catabolic reactions in the cell

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

What is Reducing power?

A

Carriers of energy/electrons NAD+/NADP+

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

Photoautotroph

  • Carbon source
  • Energy source
A
  • CO2 (inorganic carbon)

- Light

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

Chemoheterotroph

  • Carbon source
  • Energy source
A
  • Organic compounds

- Chemical compounds

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

Photoheterotroph

  • Carbon source
  • Energy source
A
  • Organic compounds

- Light

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

Chemoautotroph

  • Carbon source
  • Energy source
A
  • CO2 (inorganic carbon)

- Chemical compounds

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

Photoautotroph Examples

  • 3 for Oxygenic
  • 2 for Anoxygenic
A
  • Plants, algae and cyanobacteria

- Photosynthetic green sulphur and purple sulphur bacteria

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

Chemoheterotroph

  • 4 for Aerobic respiration
  • 4 for Anaerobic respiration
  • 3 for Fermentation
A
  • Animals, fungi, protozoa and many bacteria
  • some animals, protozoa, bacteria and archaea
  • some bacteria, fungi (yeasts) and archaea
22
Q

Oxygenic photoautotrophs

A

Carry out photosynthesis aerobically and use H2O to reduce CO2, producing O2 as a by-product.

23
Q

Anoxygenic photoautotrophs

A

Carry out photosynthesis anaerobically (do not use H2O nor produce O2.
Eg sulphur bacteria use H2S to reduce CO2, producing S as a by-product.

24
Q

Functional food

A

Food claimed to have a health-promoting or disease-preventing property beyond the basic function of
supplying nutrients.

25
Q

Probiotic.

A

Live microorganisms which when ingested in adequate amounts confer a health benefit on the host.

26
Q

What types of bacteria are commonly used as probiotics?

A

Majority of probiotics are Gram positive, lactic acid producers
Bifidobacterial species and Lactobacillus species.

27
Q

Draw a diagram depicting the structure of a bacteriophage.

A

the bacteriophage DNA
the tail sheath
the head
the tail fibres.

28
Q

Lysogenic cycle

A

Viral genome inserted into the bacterial chromosome and lies dormant,
replicating with the bacterial cell and being passed on to all daughter cells until it is induced to leave the chromosome

29
Q

Lytic cycle

A

Replication cycle that results in cell death and release of phage particles

30
Q

Prophage

A

Inactive bacteriophage genome inserted into a specific site on a bacterial host cell’s chromosome.

31
Q

FOUR stages of microbial pathogenesis.

A
  • Adherence to host cells
  • Invasion of host tissues
  • Replication within host tissues
  • Disease causing damage to host tissues
32
Q

Adherence

  • list a bacterial virulence factor
  • how it contributes to the virulence of the bacteria?
A

Adhesions – bind to host cell

33
Q

Invasion of host tissues

  • list a bacterial virulence factor
  • how it contributes to the virulence of the bacteria?
A

Motility – move through mucus

Internalin-related proteins (invades host)

34
Q

Replication within host tissues

  • list a bacterial virulence factor
  • how it contributes to the virulence of the bacteria?
A

Siderophores – bind iron

Capsules – resist phagocytosis

35
Q

Disease causing damage to host tissues

  • list a bacterial virulence factor
  • how it contributes to the virulence of the bacteria?
A

Endotoxins – cause inflammation/fever

Exotoxins – can be cytotoxins, neurotoxins, enterotoxins.

36
Q

Selective toxicity

  • My answer
  • worksheet answer
A

Chemical ‘magic bullet’ to kill microbial cells but not the host cells.

Effective antimicrobial agent must be more toxic to a pathogen than to the pathogen’s host. E.g. the antimicrobial agent kills microbial cells without damaging the host cells.

37
Q

Most important cause of genetic diversity in microbial populations.

A

Mutations

38
Q

Mutations can be

A 
Spontaneous (occur randomly)  
Environmental causes (such as UV light, radiation etc.)
39
Q

Draw FIVE key target sites of antimicrobial activity within a bacterium

A
  • Cell wall synthesis (inhibition of peptidoglycan)
  • Protein synthesis (ribosomes)
  • Cytoplasmic membrane
  • Metabolic pathways/metabolites/binding site of proteins or receptors
  • DNA or RNA synthesis
40
Q

4 Ways to slow or prevent antibiotic resistance from occurring.

A
  • Decrease antibiotic utilization
  • Improve diagnostics
  • Identify new targets
  • Combination therapies
41
Q

Features of the bacterial genome.

A
  • Single circular chromosome.
  • No nuclear membrane (chromosome restricted to nucleoid).
  • Plasmids (small, circular, self-replicating DNA molecules).
42
Q

Vertical gene transfer

A

cells replicate their genomes and pass copies to their daughter cells

43
Q

Horizontal gene transfer

A

prokaryotes acquire genes from other microbes of the same generation

44
Q

Draw a diagram outlining the stages of an infectious disease.

A 
X axis (vertical) = Number of microorganisms or intensity of signs or symptoms
Y axis (horizontal) = time
Incubation period
Prodromal period
Illness stage
Decline
Convalescence
45
Q

spread of disease involves six components which must be present for an infection to spread from one person to another (the chain of infection).
what are they?

A
  • Causative agent (e.g. bacteria, parasite, virus)
  • Reservoir/source (e.g. human, animal, fomite, food, water)
  • Means of exiting the body (e.g. excretions, secretions, droplets)
  • A mode of transmission to spread the infection (e.g. contact, airborne, vector)
  • Portal of entering the body (e.g. respiratory, GI, GU, mucous, skin)
  • A person at risk (e.g. young/elderly, immunocompromised)
46
Q

Infectious diseases can be classified epidemiologically into four categories:

A

Endemic
Sporadic,
Epidemic
Pandemic.

47
Q

HIV is a retrovirus. Explain what the term retrovirus means.

A 
HIV synthesises DNA from its RNA genome. This is reverse (“retro”) of the usual DNA to RNA
information flow (Reverse transcription).
48
Q

Draw a phylogenetic tree of sequences of a virus taken
from different tissues of a single individual.

What does the tree tell you about the relationships between the viral genome sequences?

A

L36

Viruses in each individual tissue are more closely related to each other than they are to viruses from other tissues.

49
Q

Draw a phylogenetic tree of sequences of a virus taken
from different tissues of a single individual.

How would you explain this pattern of relatedness?

A

L36

Single viruses infect individual tissues and then remain in those tissues where they evolve.

50
Q

What are the Selection pressures that the HIV virus is under within an individual patient?

A

The immune system
Drug regimen
Changes in the receptor
Tropism in tissues

CELS MCQ & Structure (6 decks)

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