Brainscape's Knowledge GenomeTM

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


See full index

Microbiology > Bacteria - Metabolism, Transmission, Relationships, Infection Mechanisms, and Invasion > Flashcards

Bacteria - Metabolism, Transmission, Relationships, Infection Mechanisms, and Invasion Flashcards

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

What pH do most bacteria grow best at?

A

a neutral pH (7)

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

In regards to CO2, what type of environment do bacteria grow better?

A

in an environment containing a small amount (5-10%) of CO2

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

In regards to oxygen, what are the byproducts of the metabolic processes of some bacteria?

A

highly toxic forms of oxygen such as 2O2 and H2O2

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

In regards to oxygen, how do bacteria live in it?

A

they either need to have a means of detoxifying oxygen or they need to grow in environments where oxygen does not occur

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

What is 2O2 broken down by?

A

superoxide dismutase

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

What is H2O2 broken down by?

A

catalase and peroxidase

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

What are the types of bacteria (in regards to oxygen, i.e anaerobe etc.)

A

strict aerobes, strict (obligate anaerobes, facultative anaerobes, and microaerophiles

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

What is an example of a strict aerobe?

A

pink eye in cattle

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

What is an example of a microaerophile?

A

leptospira

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

What are the sources of infectious agents of bacteria?

A

animals and humans, and inanimate nature

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

What is the general normal flora for bacteria?

A

skin, mouth, stomach, small intestine, large intestine, etc.

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

Define incubation period.

A

period from the time of infection until clinical signs appear

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

What is a convalescent carrier?

A

those who have recovered from their illness but remain capable of transmitting to others

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

What is a contact carrier?

A

when you acquire the microorganism from contact with the infected

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

What is subclinical infection?

A

an infection that is nearly or completely asymptomatic

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

What are some sources of infection?

A

droplet, dust, ingestion, contact, wounds, injection, via genital tract, transplacental, umbilical, and nosocomial

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

What are heterotrophs?

A

organisms incapable of using either light or inorganic compounds as an energy source or of using CO2 as a sole carbon source

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

What are saprophytes?

A

heterotrophs that live on dead or decaying organic matter - most pathogenic bacteria

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

What is a commensal relationship?

A

doesn’t cause disease

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

What is a opportunist relationship?

A

normally harmless in their usual environment but cause disease when they gain access to other sites or tissues

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

What is an obligate pathogen?

A

a parasite that cannot complete its lifestyle without exploiting a suitable host

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

What are Koch’s postulates?

A
  1. the organism must be regularly isolated from cases of the disease
  2. it must be grown in vitro in pure culture
  3. a pure culture should produce the typical disease when inoculated into a susceptible animal
  4. the same organism must be isolated from the experimentally induced disease
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What are the three components of colonization of mucosal surfaces?

A

association, adhesion, and invasion

24
Q

What is association?

A

localization of bacteria on or near the cell surface - they may associate with mucus or exudates, establish small numbers of noncovalent bonds with the surface or respond to chemotactic factors

25
Q

What is bacterial adhesion?

A

stable, irreversible attachment of a bacterium to a mucosal surface

26
Q

What is bacterial adhesion usually between?

A

specific surface proteins of the bacterium and carbohydrate-containing molecules on the eukaryottic cell surface or glycocalyx

27
Q

What are hemagglutinins?

A

molecules which mediate agglutination of erythrocytes that may also function as adhesions

28
Q

What is adhesion greatly affected by?

A

the electrostatic charge and hydrophobicity of the cell surfaces that interact

29
Q

What is the Derjaguin-Landau and Verwey-Overbeek (DLVO) theory?

A

two rigid bodies of like charge approach each other they are affected by attractive and repulsive forces, which vary independently with the distance between the bodies

30
Q

Over what distance is there a net force of attraction?

A

> 10nm

31
Q

Over what distance is there net repulsive force?

A

1 - 10 nm

32
Q

Over what distance is there a strong attractive force?

A

distance of less than 1 nm

33
Q

What happens to the presence of repulsive force as the radii of curvature decreases?

A

the repulsive force is less and may be able to bridge the intermediate zone of repulsive forces and establish a stable receptor-ligand bond

34
Q

What cations help bridge the intermediate zone?

A

Fe3+ and Ca2+

35
Q

What can proteinaceous adhesions be divided into categorically?

A

those with fimbrial morphology and those lacking definite shape and size

36
Q

Describe fimbrial adhesions.

A

filamentous structures that vary from 2-7 nm in diameter and which extend up to 4 micrometers from the bacterial surface

37
Q

Describe type 1 fimbriae.

A

closely related to F6 fimbriae
relatively rigid structure, a uniform cross-sectional diameter, and an axial hole
subunits are arranged as a helical structure
tends to aggregate into highly ordered, parallel bundles

38
Q

Describe nonfimbrial proteinaceous adhesions.

A

adhesions that lack a definite structure and often take the form of secreted proteins or proteins associated with the outer membrane

39
Q

What is an example of a species that has a nonfimbrial proteinaceous adhesion?

A

staphylococcus aureus

40
Q

How does lipoteichoic acid bind to eukaryotic cells?

A

by interacting with a fibronectin receptor

41
Q

What is expression of bacterial adhesions affected by?

A

the conditions under which the organisms grow both in vitro and in vivo

42
Q

When do type 1 fimbriae grow?

A

in cultures of organisms grown in static broth culture beyond late log phase but they are not produced in cultures grown on agar media

43
Q

What do mucosal cells of host tissues have on their surfaces and what do they do?

A

glycoproteins and glycolipids which act as receptors for hormones, nutrients, and a variety of other molecules as well as carbohydrate receptors that provide binding sites for bacterial adhesions and toxins

44
Q

What is an extracellular parasite?

A

organisms that reside out of eukaryotic cells

45
Q

What is a facultative intracellular parasite?

A

an organism that has the capacity to grow and survive both inside and outside of eukaryotic cells

46
Q

Do extracellular parasites or facultative intracellular parasites live longer?

A

facultative intracellular parasites

47
Q

What is an obligate intracellular parasite?

A

parasites that can only grow within cells

48
Q

Provide an example of a parasite that can gain entry by trauma or puncture.

A

Clostridium tetani

49
Q

Provide an example of a parasite that can gain entry by endocytosis.

A

Salmonella typhimurium

50
Q

Provide an example of a parasite that can gain entry via receptor mediated endocytosis.

A

Chlamydia psittaci

51
Q

Provide an example of a parasite that can gain entry via uptake by antigen sampling sites.

A

Salmonella sp

52
Q

Provide an example of a parasite that can gain entry via disruption by cytotoxins.

A

Salmonella sp

53
Q

Provide an example of a parasite that can gain entry via direct penetration.

A

Leptospira

54
Q

Which of the types of invasion is not a true invasion?

A

trauma or puncture

55
Q

Explain the process of endocytosis.

A

eukaryotic cells invaginate and engulf the bacteria in a membrane-bbound vacuole that is similar to the phagocytic vacuole of neutrophils and macrophages

56
Q

What specific structure is required for endocytosis?

A

contractile proteins

Microbiology (50 decks)

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