Brainscape's Knowledge GenomeTM

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


See full index

BS127 - Agents of Infectious Disease > Lecture 3 > Flashcards

Lecture 3 Flashcards

1
Q

What are systematics?

A

Study of the diversity of organisms and their relationships

Links phylogeny with taxonomy

Molecular technology to chase evolutionary relationships

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

How are names given to bacterial species?

A

Genus/ species names are always written in italics

Name reflects something about the organism

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

Why is species interbreeding and producing viable offspring problematic in microbiology?

A

Asexual reproduction

Lateral gene transfer

Phenotypic and genotypic plasticity of microorganisms

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

What is the definition of no unified species concept?

A

A group of strains that show a high degree of overall similarity and differ considerably from related strain groups with respect to many independent characteristics

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

What is phenotypic analysis?

A

Morphological, metabolic, physiological and chemical characteristics

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

What is genotypic analysis?

A

Comparative at the gene and genome level

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

What is phylogenetic analysis?

A

Framework of evolutionary relationships

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

What is the 3 categories of polyphasic bacterial taxonomy?

A

Phenotypic

Genotypic

Phylogenetic

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

What is the problem with phenotypic analyses?

A

A single mutation can change apparent definition of a species

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

What is motility?

A

Determination by phase-contrast microscopy

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

What is nutritional testing in organisms?

A

Testing for ability to grow on a range of compounds as sole sources of carbon, energy and nitrogen

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

What is the gram staining procedure?

A

Using stained cells to visualise them

  1. Spread culture thinly
  2. Dry slowly
  3. Place slide through flame
  4. Stain cells and add iodine solution
  5. Wash slide with alcohol
  6. Gram +ve stays purple, Gram -ve stain washes off
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are phenotypic biochemical tests?

A

Decomposition of simple carbohydrates

Acid from glucose in anaerobic or aerobic conditions

Fermentation produces acids and changes pH inducing colour change

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

What is the DNase test?

A

Colonies producing DNase hydrolyse DNA

If medium is flooded and acidified with 1 N HCl, DNA precipitated out and clear zones appear around DNase +ve colonies

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

What are the cultural characteristics looked for in organisms?

A

Colony shape
Elevation
Surface appearance
Texture
Pigmentation
Odour

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

What is an acidophile?

A

pH <6

17
Q

What is an alkaliphile?

A

pH > 8

18
Q

What is a barophile?

A

Requires high pressure

19
Q

What is a halophile?

A

Requires very salty conditions

20
Q

What is a microaerophile?

A

Requires low oxygen concentration

21
Q

What is a psychrophile?

A

Requires low temperature (<15)

Inhabit permanently cold environments

Adapted to low temperatures: proteins more flexible, membranes more fluid

22
Q

What is a mesophile?

A

Requires normal temperature (15-45)

23
Q

What is a thermophile?

A

Requires high temperature (>50)

24
Q

What is a hyperthermophile?

A

Very high temperature (>80)

25
Q

What is molecular analysis using Fatty Acid Methyl Ester (FAME)?

A

Determines fatty acid profile of membrane lipids

Growth under ‘standard’ conditions

Extract lipids and chemically modify to methyl esters – analyse using gas chromatography

26
Q

How is the fatty acid profile of membrane lipids determined?

A

Differences in chain length

Presence of double bonds, ring, branched chains of hydroxyl groups

Compare chromatograms to database for best match

27
Q

What are the drawbacks of determining the fatty acid profile of membrane lipids?

A

Fatty acid profile on growth conditions which need to be standardised

Not all strains can be cultivated under those conditions

28
Q

What is DNA hybridisation for genotyping analysis?

A

Genome wide comparison of sequence similarity

Useful for discrimination of strains of a species

29
Q

What is AFLP for genotyping analysis?

A

Amplified fragment length polymorphism

PCR targeting repetitive elements in bacterial genome

Used to distinguish closely related strains

Analyses of results is comparison of electrophoretic patterns

30
Q

What is MLST for genotyping analysis?

A

Multilocus sequence typing

Characterising strains within a species

Amplify target gene, sequence, determine alleles and compare with other strains of same species

31
Q

What is GC base ratio for genotyping analysis?

A

Percentage of GC bases in genome

Similar organisms have close GC content

32
Q

What is DNA sequencing with genotyping analysis?

A

Using fluorescent dyes and a capillary column

Read sequence and compare actual sequence

Amplify a specific section of DNA, can target specific populations or functional groups

Can build genomes rapidly using NGS

BS127 - Agents of Infectious Disease (4 decks)

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