Brainscape's Knowledge GenomeTM

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


See full index

Phase 2a - ICS > Microbiology > Flashcards

Microbiology Flashcards

1
Q

What is a pathogen?

A

An organism that causes or is capable of causing disease.

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

What is a commensal bacteria?

A

Organism which colonises the host but causes no disease in normal circumstances.

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

What is an opportunist pathogen?

A

Microbes that only cause disease if host defences are compromised.

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

Define virulence/pathogenicity:

A

The degree to which a given organism is pathogenic.

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

What is asymptomatic carriage?

A

When a pathogen is carried harmlessly at a tissue site where it causes no disease.

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

The bacterial nomenclature includes:

A

Genus and species i.e. Staphylococcus aureus.

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

What areas are open to bacterial colonisation?

A

Mucosal surfaces

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

Bacterial classification is based on:

A

Morphology: coccus, bacillus (rod)

+

Gram stain: positive (purple) and negative (pink)

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

Cocci can be:

A

Diplococcus: in pairs
Chain of cocci
Cluster of cocci

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

Rods can be:

A

Chain of rods
Curve rod (vibrio)
Spiral rod (spirochaete)

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

What stains are used in the Gram stain?

A

Crystal violet
Iodine
Decolourisation
Counter stain with saffranin

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

What temperature range do bacteria survive?

A

<-80 to +80 degrees (120 Celsius for spores)

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

What pH range do bacteria live in?

A

<4-9

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

How long can bacteria live without water?

A

2 hours - 3 months (>50 years for spores)

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

Can bacteria survive UV light?

A

Yes - some species.

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

Growth rate of viruses

A

Most viruses need cells and doubling time <1 hour.

17
Q

Growth rate of E. coli and S. aureus

A

Needs broth or solid media, doubling time takes 20-30 mins.

18
Q

Growth rate of Mycobacterium tuberculosis

A

Needs broth or media, doubling time takes 24 hours.

19
Q

Growth rate of fungi (Candida albicans)

A

Needs broth or media, doubling time takes 30 mins.

20
Q

Growth rate of Mycobacterium leprae.

A

Needs borth or media, doubling time 2 weeks.

21
Q

Endotoxin

A

Component of the outer membrane of bacteria, e.g. LPS in Gram negative bacteria.

It has a non-specific action, stable to heat, weak antigenicity and is not convertible to toxoid.

22
Q

Exotoxin

A

Secreted proteins of Gram positive and Gram negative bacteria. I.e. Tetanus toxin

It is a protein, with specific action, labile to heat, has strong antigenicity and can be converted to toxoid.

23
Q

Bacterial DNA

A

ds DNA

24
Q

Where does transcription and translation take place in bacteria?

A

In the cytosol (30S and 50S ribosomes)

25
Q

Bacterial genetic variation is due to mutation:

A

Base substitution, deletion or insertion.

26
Q

Gene transfer

A

Transformation via plasmid
- Promotion genes
- Antibiotic and virulence determinant genes
- Maintenance genes

Transduction via phage.

Conjugation via sex pilus.

27
Q

Examples of obligate intracellular bacteria?

A

Rickettsia spp.
Chlamydia spp.
Coxiella

28
Q

MacConkey Agar is used for

A

Enteric bacteria

29
Q

Bacteria that can be cultured on artificial media can be grouped based on:

A

Cell wall.

The one with no cell wall: mollicutes spp. (Mycoplasma pneumoniae)

30
Q

What are the groups of bacteria belonging to With a cell wall and growing as filaments?

A

Actinomyces
Nocardia
Streptomyces

31
Q

Bacteria with cell wall and growing as single cells:

A

Rods
Cocci
Spirochaetes

32
Q

What bacteria belong to spirochaetes?

A

Leptospira
Treponema
Borrelia

33
Q

Gram negative cocci is grouped as:

A

Anaerobic: Veillonella

Aerobic: Neisseria (N. meningitidis; gonorrhoeae)

34
Q

Gram positive cocci is grouped as:

A

Aerobic: Staphylococcus and Streptococcus.

Anaerobic: Peptostreptococcus

35
Q

Streptoccus can be:

A

Beta haemolytic: S. pyogenes
Alpha haemolytic S. pneumoniae and oralis
Non-haemolytic S. bovic.

Enterococcus (E. faecalis)

36
Q

Lancefield group

A

Beta haemolytic streptococci are further differentiated / classified according to the properties of the antigens on their cell wall and given letters of the alphabet. This is known as the Lancefield grouping, hence ‘group A streptococci’ as an alternative name for S. pyogenes.

37
Q

Rods - Zielh-Neelsen stain positive

A

Mycobacteria

38
Q

Gram positive rods can be

A

Anaerobic: Clostridium spp and Propionibaterium spp.

Aerobic: Corynebacterium spp, Listeria spp, Bacillus spp.

39
Q

Gram negative rods

A

Anaerobic: Bacteroides

Aerobic: Vibrio, Campylobacter, Helicobacter, Haemophilus, Brucella, Bordetella, Pasteurella

Facultative anaerobic: Coliforms (Escherichia, Klebsiella, Salmonella, Shigella, Citrobacter , Proteus, Yersinia, Pseudomonas

Phase 2a - ICS (43 decks)

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