Microbial World and Bacterial Structures (complete) Flashcards Preview

DMD 5245 > Microbial World and Bacterial Structures (complete) > Flashcards

Flashcards in Microbial World and Bacterial Structures (complete) Deck (109):
1

What are the 6 types of microbes

1. Fungi
2. Protozoa
3. Algae
4. Prokaryotes (bacteria and Archaea)
5. Small Animals (helminths)
6. viruses

2

list the 6 types of microbes from smallest to largest

1. viruses
2. prokaryotes
3. protozoa
4. algae, small animals, and fungi

3

what are the three things that revolutionized human health against infectious disease

1. chlorination of water
2. Immunization
3. antibiotics

4

What are Fungi?

Eukaryotic heterotrophs that can be multi-cellular or unicellular with cell walls composed of Chitin and beta-glucans,

5

What are unicellular fungi called

Yeasts

6

what are multicellular fungi called

molds

7

how do yeasts reproduce

asexually by budding

8

how do molds reproduce

by sexual and asexual spores

9

which type of miccrobe causes:
ringworm
yeast infections (candidiasis)
histoplasmosis
coccidioidomycosis
cryptococcosis
pneumocystis pneumonia

fungi

10

What are protozoa

single-celled eukaryotes

11

where do you find protozoa

typically living freely in water, but some live inside animal hosts

12

how do protozoa reproduce

most often asexually

13

how are protozoa classified and what are the three classes of protozoa

they are classified by means of locomotion
1. pseudopodia
2. cilia
3. flagella
4. Non-motile

14

what are pseudopodia

cytoplasmic extensions that flow in the direction of travel

15

what are cilia

many short hair-like protrusions that propel protozoa

16

what are flagella

few, long, and whip like extensions that spin and move protozoa

17

What are algae

photosynthetic microbes with simple reproductive structures that can be either unicellular or multi-cellular.

18

are algae pathogenic

No, with one exception, their role in red tides and shellfish poisoning

19

What are prokaryotes

small unicellular and non-eukaryotic microbes

20

where do you find prokaryotes

any where there is moisture, even extreme environments

21

how do prokaryotes reproduce

asexually

22

what are the two kinds of prokaryotes

bacteria and archaea

23

What is found in bacterial cell walls, that helps distinguish them from other cells

peptidoglycan

24

are any known diseases caused by archaea

no

25

what are helminths

parasitic worms

26

what are the three main types of helminths

Cestodes = tapeworms (taenia)
Trematodes = Flukes (Schistosoma)
Nematodes = Roundworms (Ascaris)

27

What types of microbe causes malaria and amebiasis

protozoa

28

what type of microbe causes shellfish poisoning

algaea

29

what type of microbe causes TB and diphtheria

Bacteria (prokaryotes)

30

what type of microbe causes AIDS, influenza, West Nile, and SARS

virus'

31

What is resolution/resolving power of an eye, or microscope

the closest you can get two objects to each other and still see them as separate

32

what two things influence resolution/resolving power

the wavelength of radiation, and the Numerical Aperature (this is basically how perfect the lense is)
Wavelength/NA = resolving power

33

is a microscope with a large or small resolving power value more able to see smaller things with better detail

smaller values mean they are more able to see small things better

34

What are the resolving power values for the Human eye, light microscopes, and electron microscopes

Eye = .2 milimeters
Light microscope = .2 micrometers
electron microscope = .2 nanometers

35

What is a bright-field microscope

a microscope with a series of lenses, with light rays that pass through the specimen into the objective lens

36

when should you and when shouldn't you use immersion oil?

you should use it when observing things with a light microscope with high magnification, and not when using low magnification

37

What is a Dark field microscope

a light microscope in which there is a filter that blocks direct light from reaching the specimen, all the light that hits it is from an obtuse angle. The image will have a dark background, and anything that refracted light will show up as a bright spot

38

when do you use a dark field microscope

when observing thin, or pale objects that are moving

39

what are phase microscopes

microscopes that read light rays that are out of phase different from those in phase. more dense objects show up bright, less dense ones show up dark

40

when are phase microscopes used

when examining living organisms that would be damaged by attaching them to slides or staining them

41

what are the two types of phase microscopes

phase-contrast
Nomarski DIC

42

what are fluorescent microscopes

microscopes that use direct UV light, things that are naturally fluorescent or have been stained to be so, show up as visible light

43

What is an electron microscope

microscopes that use electrons instead of light, and due to their vastly smaller wavelength they have much greater magnification potential

44

what are the two types of electron microscopes

TEM (transmission electron microscopes)
SEM (scanning electron microscopes)

45

why do you need to heat-fix a specimen to the slide

1. it fixes the organism to the slide
2. it kills the organism

46

why do we stain specimens for microscopy

to increase contrast and resolution

47

what type of dye would you use to stain alkaline structures

acidic dyes

48

what type of dye would you use to stain acidic structures

basic dyes

49

What are simple stains

one stain used to highlight a structure

50

what are differential stains, and what are some examples

when more than one stain is used to highlight multiple structures.
Gram Stain
Acid Fast Stain
Endospore stain

51

what is a gram stain

a stain which helps you differentiate between Gram + and Gram - bacteria.
Gram + is dark purple
Gram - is pink

52

what is an acid fast stain

a stain that highlights Acid-Fast Bacteria (mycobacteria). you know it's acid fast bacteria because the stained bacteria doesn't lose it's color even when washed with acid

53

what is an endospore stain

a stain that highlights endospores, heat is used to push staining into the endospore

54

what is a negative (capsule) stain

a stain in which everything is stained, with the exception of the capsule of the microbe.

55

What is a flagellar stain

a stain in which a mordant is used to coat the flagella, making it large enough to be seen, and then it is stained so you can see the flagella

56

What are glycocalyces

Gelatinous sticky substances surrounding the cell, made of polysaccharides.

57

What are the two types of glycocalyces

capsule
slime layer

58

What is the difference between the capsule and slime layer (the two types of glycocalyces)

the capsule is thicker and more firmly attached to the cell surface

59

What are the main functions of glycocalyces

Protects the cell from drying out
helps prevent the host from recognizing the cell
helps the prokaryote attach to surfaces

60

What is the function of flagella

movement of prokaryotes

61

what are the parts of flagella

a filament, the long hollow tail made of helical proteins around a hollow core
a hook, the curved part that connects the filament into the basal body
a basal body, connects the hook and filament into the cell wall

62

how many degrees is flagella capable of rotating

360 degrees

63

Are flagella soft and flexable, or rigid

rigid

64

What is the name for prokaryotes with only one flagella

monotrichous

65

what is the name for prokaryotes with many flagella on one end

lophotrichous

66

What is the name for prokaryotes with two flagella on opposing ends

amphitrichous

67

what is the name for prokaryotes with many flagella all over

peritrichous

68

Can rotation be both clockwise and counterclockwise

Yes

69

What are the two types of movements for prokaryotes with multiple flagella

run (movement in a single direction for some time)
and tumble (abrupt and random changes in direction)

70

when and how does a prokaryote with multiple flagella run

it runs in the direction of favorable stimuli, and it runs by grouping all of the flagella in one bundle and rotating them

71

When and how does a prokaryote with multiple flagella tumble

it tumbles in response to unfavorable stimuli, and it tumbles when all of the flagella rotate randomly, not in the same direction

72

how does a prokaryote with internal flagella move

the internal flagella cause the body of the prokaryote into a cork screw and the prokaryote cork screws and moves foreward

73

What are fimbriae

short, sticky, bristle like projections that are used by bacteria to adhere to things

74

what are pili

hollow tubes of pilin that are shorter than flagella, but longer than fimbriae. they are used to connect two bacteria together for conjugation

75

which type of extension is important in biofilms
flagella, fimbriae, or pili

fimbriae

76

what is conjugation for bacteria

when two bacteria are connected by pili, and one bacteria shares it DNA with the other

77

why is the cell wall of bacteria used as a target for antibiotics

because animal cells don't have cell walls, they are specific to bacterial cells

78

What is found in all cell walls, and no where else, and is a target of many antibiotics

peptidoglycan

79

What are the main functions of prokaryotic cell walls

provides structure
protects the cell from osmotic forces
keeps some antimicrobials out
assists in attachement

80

What is the structure of peptidoglycan

long sugar chains that are cross linked by peptides

81

What is unique about the peptides that form the cross links in peptidoglycan

some are D-amino acids, which are very rare in nature

82

What are the four different types of cell walls

1. Gram positive cell walls
2. Gram negative cell walls
3. Acid fast cell walls
4. Archaea cell walls

83

What are the key characteristics of Gram positive cell walls

1. they have a thick peptidoglycan layer
2. the peptidoglycan layer has techoic acids
3. those techoic acids link to lipids to become lipotechoic acid, which helps hold the peptidoglycan to the cell membrane

84

what are the key characteristics of Gram negative cell walls

1. They have a thin peptidoglycan layer
2. They have an inner and outer bilayer membrane (peptidoglycan in the middle)
3. They have lipopolysaccharide (LPS)

85

Why is LPS of gram negative cells signigicant? and what is another name for it?

it is toxic to animals, and it is called endotoxin

86

lipopolysaccharide is a union between which two things

a lipid and a sugar

87

what is the lipid portion of LPS called

Lipid A

88

What happens to Lipid A when a gram negative bacteria dies

Lipid A is released from the cell and can cause fever, vasodilation, inflammation, shock, and blood clotting

89

What are the key characteristics of an Acid Fast cell wall

1. contains layers of a wax like lipid
2. made up of mycolic acids
3. They are very protected from antimicrobials

90

What is the periplasmic space

the space between the outer membrane and plasma membrane of gram negative bacteria where the peptidoglycan layer resides

91

What is signigicant about archaeal cell walls

they don't contain peptidoglycan, but can still be Gram positive and Gram negative

92

What are archaeal hami

little grappling hooks archaea used to hook on to things

93

What are the two main things in fungal cell walls

Chitin and Beta glucans

94

What shape is a coccus prokaryotic cell

a sphere

95

what shape is a coccobacillus prokaryotic cell

a slightly elongated sphere

96

what shape is a bacillus prokaryotic cell

an elongated sphere (longer than a coccobacillus)

97

What is the most common method of reproduction among prokaryotes

binary fission

98

what is binary fission

when a prokaryote replicates its DNA and the cell just splits into two cells

99

What does STREP-tococci mean

it means a linear line of spherical shaped prokaryotes

100

what does STAPH-ylococci mean

a random mass of spherical shaped prokaryotes

101

What are the two families of Gram-Positive rods that make endospores

Bacillus and Clostridium

102

Is an endospore a reproduction mechanism

no, it is a defense mechanism

103

how many endospores can one vegetative (normal) prokaryotic cells produce

1

104

how many vegetative cells can be produced from one endospore

1

105

What makes endospores capable of surviving for such a long period of time?

1. Extremely dehydrated
2. Extremely resistant to drying, heat, radiation, and chemicals
3. almost completely ametabolic

106

Where in the prokaryote bacillus will you find their endospores being created?

Central, terminal, and subterminal

107

What is found in the cytoplasm of prokaryotes

cytosol
inclusions
ribosomes
cytoskeleton

108

Where in the prokarytoe clostridium do you fin their endospores being created

Terminal only

109

do the endospores of bacillus of clostridium cause the swelling of the body of the prokaryote

clostridium endospores cause their body to swell around the forming endospore. and because their endospores always form terminally they look a little like tennis rackets