Brainscape's Knowledge GenomeTM

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


See full index

Biology - Microbiology > Biochemistry - Pathogenesis and Virulence > Flashcards

Biochemistry - Pathogenesis and Virulence Flashcards

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

What two factors can describe pathogens?

A

Pathogenicity
Virulence

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

Pathogenicity

A

The ability to cause disease.

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

Virulence

A

The degree/intensity of pathogenicity

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

Infection

A

This refers to persistence of bacteria, not necessarily meaning tissue damage.

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

Disease

A

Cause overt damage to the host, where body parts cannot fulfill normal function.

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

Kochs Postulates

A

These are a set of criteria used to establish relationship between micro-organisms and disease.

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

When were Koch’s Posutlates proposed?

A

By Robert Kock in late 19th century.

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

What is the first Koch Postulate?

A

Micro-organism msut be present in all cases of the disease, isolated and identified in every individual with it.

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

What is the second Koch Postulate?

A

Isolation from the host and grown in pure culture, for identification of cause-and-effect relationship between organism and disease.

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

What is the third Koch Postulate?

A

Must cause the same disease when inoculated into a healthy hot.

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

What is the fourth Koch postulate?

A

Re-isolation from inoculated, diseased host and identifed as being identical to the original microorganism

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

What diseases were discovered using Kochs Postulates?

A

Anthrax, TB and Cholera

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

What is the basis of Koch’s Postulates?

A

This is taking of an animal, isolating microorganisms from the diseases then re-injecting into lab animal.

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

What are the two types of Pathogen?

A

Oppurtunisitc
Primary(Obligatory

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

Oppurtunisitc Pathogen

A

These are microbes causing disease in immunocompromised hosts, less so in healthy patients.

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

Obligatory Pathogens

A

These can cause disease in absence of immune defects, needing disease to survive.

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

What are the stages of infection for pathogens?

A

Emerge from Reservoir
Transport To Host
Adherrence/Colonisation
Tissue Invasion

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

How may host transport be facilitated?

A

Direct like sneezing, airborne, body contact.
Indirect like vectors(Zoonosis) or arthropods, vehicles, food, water, soil etc.

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

What are the requirements of adherence?

A

Adhesins
Host Cell-Receptors
Biofilm FormatioN

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

Adhesins

A

These are virulence factors allowing bacteria to attach to host cells

21
Q

What is the structure of Adhesin?

A

Extension from pili, fimbriae, flagella.

22
Q

What are examples of host cell receptors?

A

Integrins, Cadherins or Glycosaminoglycans.

23
Q

Why might biofilm formation be important?

A

Body has mechanisms to remove bacteria

24
Q

Extracellular Polymeric Substnaces

A

This is an adhesive matrix anchoring bacteria into place, regulated by quorum sensing for co-ordinated behaviour

25
Q

What is an example of host recogntion?

A

Streptococcus binding salivary glycoproteins and hydroxyapatite, adherring to teeth.

26
Q

How might pathogens have to compete with microflora?

A

Nutrient acquistions, toxin production, biofilm formation and immune evasion.

27
Q

What is the process of adherrence?

A

Non-specific forces like charge/hydrophobicity, then specific bacterial adhesins and host receptors.

28
Q

How do non-specific interactions faciliaate bacterial binding?

A

Net surface charge of bacteria is negative due to LPS and teichoic acids

29
Q

What is an example of invasion?

A

E.coli strands binding urinary tract cells by pili and adhesin production through chaperone-usher pathway, guiding pilin assembly of subunits into a filamentous structre.

30
Q

How might strains bind Brush Border Villi?

A

Capsules and decay-acceleration factor on intestinal epithelial cells.

31
Q

Biofilm

A

This is the secretion of a matrix of extracellular polymeric substances assisting in 3D community development to protect bacterial from external stressors.

32
Q

What is EPS secretion of biofilms facilitated by?

A

Genes and environmental cues, like quorum sensing.

33
Q

What are examples of adhesins specific to host receptors?

A

Fimbriae and Pili, Capsules, S-Layers, Flagella or Teichoic acids.

34
Q

Siderophores

A

These are small, high-affinity, iron-binding molecules chelating iron from host proteins and transporting it into bacterial cells.

35
Q

How is siderophore protein production regulated?

A

Transcriptional regulators that respond to envrionmental iron levels

36
Q

Transferrins

A

This is a blood plasma binding and transporting iron throughout the body, synthesised and secreted by the liver.

37
Q

What is an example of a siderophore?

A

Sigma Factor PVDS regulating pyoverdine production in P.aeruginosa in response to low iron.

38
Q

What are the barriers to bacterial infection?

A

Lysozymes in tears
Skin
Mucus in lungs
Cilia in respiratory systems
Flora competition

39
Q

How do lyzozymes work?

A

Cleavage of the glycosidic bond connecting PG in the bacteria cell wall leading to lysis.

40
Q

How does the mucus prevent infection?

A

Complex network by goblet cells of mucin cross-linking being gel likes

41
Q

What are examples of tissue invasion?

A

Pentration or between cells
Phagocytic cell invasion
Adhesin interaction

42
Q

How can bacteria invade phagocytic cells?

A

Adhesin interaction to neutrophil/macrophage with phagocytosis engulfment or injection of effector proteins into host cell to prevent phagosome maturation.

43
Q

How can lytic compounds be used for invasion?

A

Killing of cells, lysing area of invasion

44
Q

What lysing compounds are used?

A

Collagenase, Phospholipase and Hemolysins

45
Q

Hemolysis

A

This is the destruction of RBC.

46
Q

How might bacteria evade host immune response?

A

Bypassing IIR like phagocytic cells, complemenet system, cytokines or chemokines
AIR avoiding antibodies and T Cells.

47
Q

How can avoidance occur?

A

Prevent macrophage capture
Antibodiy production

48
Q

How do antibodies work as ah ost defence?

A

Produced by B-Cells, surrounding a microbe to prevent its attachment.

49
Q

What is an example of a bacteria colonising wounds?

A

Clostridium perfringens producing gangrene

Biology - Microbiology (19 decks)

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