Brainscape's Knowledge GenomeTM

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


See full index

Microbiology > Lecture > Flashcards

Lecture Flashcards

You may prefer our related Brainscape-certified flashcards:
Biology 101 flashcards
0
Q

Who is the father of microbiology?

A

Anton Von Leuwennock; first one to figure out how to magnify things

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

What were the parts on the first microscope?

A
  • single lens = simple microscope
  • stage was a needle
  • could magnify 100-200x
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What did Anton Von Leiwennock call microorganisms?

A

Animalicules

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

What is a compound microscope?

A

Has a dual lens system

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

How many times can microscopes magnify something today?

A

Up to 2000x

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

What two factors influence magnification?

A
  1. Contrast

2. Resolution

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

Define contrast

A

How much something stands out when compared to surrounding background

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

Define resolution

A

Ability to tell 2 points from each other

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

What ways can one enhance contrast?

A
  1. Stain the specimen

2. Modification of the light source

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

What are 3 different stains?

A

Simple stain
Gram stain
Fluorescent stain

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

What is a drawback of staining?

A

Can’t maintain viability of specimen

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

What is a positive of modification of the light source?

A

Allows for viability of specimen

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

How does a phase contrast microscope work?

A

Uses filters to align the light hitting the specimen

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

What are the two types of electron microscopy?

A

Transmission electron microscopy (TEM)

Scanning electron microscopy (SEM)

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

What is a drawback of electron microscopy?

A

Can’t maintain viability of specimen

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

Describe transmission electron microscopy (TEM)

A

Passes electrons through specimen to allow for visualization of sub-cellular structures

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

Describe scanning electron microscopy (SEM)

A

Reflects electrons off surface of specimen; detects deflected electrons and generates a 3D image of specimen allowing to see surface detail

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

Scanning electron microscope (SEM) max. Magnification

A

100,000x

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

Transmission electron microscope (TEM) max. Magnification

A

1,000,000x

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

How can you enhance resolution?

A

Better optics

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

What is the max. resolution of a light microscope?

A

0.2 μm

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

What is the max. resolution of SEM?

A

1 nm

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

What is the max. resolution of a TEM?

A

0.5 nm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is the current tree of life identification based on?

A

Genetic similarities/differences. Based on the 16s rRNA gene for prok. And archaea and the 18s rRNA gene for euk.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What are the 3 domains of life?

A
  1. Bacteria
  2. Archaea
  3. Eucarya
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Conserved regions in the 16s rRNA gene?

A
  • unspecific applications

- same among all prok.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Variable regions in the 16s rRNA gene?

A
  • group or species-specific applications

- species-specific, used to identify

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What do changes in sequences of conserved regions result in?

A

Loss of function of 16s rRNA gene (translation)

28
Q

What do changes in sequences of variable regions result in?

A
  • Not necessarily loss of function but may lead to misidentification of organism.
29
Q

Which categories are applied in naming in microbiology?

A

Class, Genus, Species

30
Q

What groups of microorganisms are included in the domains?

A
  1. viruses (not included in any of the domains)
  2. bacteria - prok.
  3. archaea - prok.
  4. fungi - euk.
  5. protozoans - euk.
  6. algae - euk.
31
Q

Differences between prok. and euk.: nucleus

A

euk. only

nucleoid in prok.- chromosomes but no membrane

32
Q

Differences between prok. and euk.: membrane-bound organelles

A

euk. only

33
Q

Differences between prok. and euk.: number of chromosomes

A
  • euk. have more than 2

- prok. have one

34
Q

Differences between prok. and euk.: cell membrane

A

both euk. and prok.

35
Q

Differences between prok. and euk.: cell walls

A
  • some euk. have

- all prok. have

36
Q

Differences between prok. and euk.: size

A
  • euk. larger
37
Q

Viruses

A
  • not living (?)
  • no metabolism
  • reproduction via host cell only
    not thought to communicate with their environment (adaptation and evolution?)
38
Q

Algae

A
  • euk.
  • oxygenic photosynthesis (O2 as waste product)
  • fix CO2 at significant rates - being looked at as solution for global warming
  • has cellulose cell walls
  • not pathogenic but dinoflagellates (red tide) do produce neurotoxins for humans (ng levels can kill)
39
Q

Protozoa

A
  • euk.
  • pathogenic/parasitic
  • have no cell walls
  • divided into groups based on motility
40
Q

Groups protozoans are divided into

A

Based on motility

  • amoeba
  • falgellates
  • ciliates
  • sporozoites
41
Q

amoeba

A
  • euk.
  • protozoa
  • amorphous (no shape)
  • motility via cytoplasmic streaming
  • eg. Entamoeba histolytica –> causes dysentary
42
Q

Flagellates

A
  • euk.
  • protozoan
  • motility via flagella
  • eg. Typanasoma spp. –> causes sleeping sickness; attacks CNS via tsetse fly; neurological disorder; eventual permanent sleep and organ failure
43
Q

ciliates

A
  • euk.
  • protozoan
  • motility via cilia
  • eg. Paramecium spp. –> feed on large complex carbs and other MOs; found in termite guts to allow for cellulose degredation
44
Q

Sporozoite

A
  • euk.
  • protozoan
  • spreads between hosts via cysts (spores)
  • obligate intracellular parasite
  • eg. Plasmodium spp. –> causes malaria; spread by mosquito (Anopheles spp.)
45
Q

Fungi

A
  • euk.
  • cell walls made of chitin (insects and cell fish have chitin cell walls too)
  • non-motile
  • grouped based on reproduction
  • primary ecological role is degradation of complex organics
  • a few are pathogenic
46
Q

Yeasts

A
  • euk.
  • fungi
  • fermentation is primary metabolism under anearobic conditions
  • produce majority of alcohols and organic acids used commercially
  • a few pathogens (vaginosis and thrush)
  • eg. Sacchoromyces cerevicea –> bakers/brewers yeast; non-pathogenic
  • do not produce spores
  • mode of reproduction is budding (uneven cell division); brewing industry monitors bud scars
47
Q

Molds

A
  • euk.
  • fungi
  • filamentous morphology; each filament called hyphae; mycilia contain many hyphae
  • mode of reproduction: produce spores (which gives mold color)
  • spores are at the tip of aerial hyphae
    eg. Penicillium spp. –> produces antibacterial penicillin; attacks cell wall on gram + cells; breaks NAM and NAG bonds; resistance forms by changing linkage of NAM and NAG bonds
48
Q

Mushrooms

A
  • euk.
  • fungi
  • filamentous
  • “mushroom” portion is reproductive structure, below is large colony of filaments
  • mode of reproduction: spores; occurs in “mushroom” gills
  • eg. Agaricus spp.
49
Q

Slime Molds

A
  • protoza or fungi?
  • degradation of complex organics
  • no cell walls
  • ameboid morphology
  • differentiate into filamentous morph. (terminal differentiation)
  • motile via cytoplasmic streaming
  • produce spores
  • show rudimentary behavior when responding to stress and in forming pore structures
  • when not stressed, individual amoeboid cells replicate
50
Q

What are the 3 basic morphologies within prokaryotes?

A
  1. coccus (s); cocci (pl)
  2. bacillus (s); bacilli (pl)
  3. spirillium (s); spirilli (pl)
51
Q

Bacteria represent _______, while archea represent _________.

A

“common” prokaryote (eg. Escherichia coli); extreme prokaryote, eg. extremes in temp., pH, salt conc., contaminated environments (eg. Thermus aquatreus)

52
Q

Bacteria and archea have similar ________ but can have different

A

structures; chemical compositions

53
Q

Cell wall of bacteria are comprised of __________, while cell wall of archea are comprised of __________.

A

peptidoglycan; pseudomurein

54
Q

Cell wall

A
  • common to all prokaryotes
  • can vary in thickness
  • located extracellular to cell membrane
  • rigid structure that is porus
  • rigidity confers morph. and maintains intracellular pressure
  • porous allows nutrients in and waste out
55
Q

Composition of bacterial cell wall

A
  • made up of peptidoglycan
  • peptidoglycan = NAM (N-acetylmuramic acid) + NAG (N-acetylglucosamine)
  • creates tortuous path for substrates to travel across
  • concentration gradient drives movement of substrates
  • non-selective but excludes based on size
56
Q

Outer membrane

A
  • phospholipid bilayer
  • fluid mosaic model
  • selective because of transport proteins
  • heavily populated by porins (open, non-selective channels) –> make OM less selective
57
Q

Cell membrane

A
  • phospholipid bilayer held together by hydrophobic forces
  • job is to prevent things from crossing
  • transport proteins make it selective
  • hydrophobicity of CM prevents movement of substrates across
  • fluid mosaic model
58
Q

Fluid mosaic model

A
  • susceptible to temp. changes
  • as temp. increases, too much fluidity and membrane falls apart
  • as temp. decreases, not enough fluidity to maintain needed nutrient transport
  • to survive temp. fluctuation some prok. can adjust ratios of saturated/unsaturated fatty acids
  • as temp. increases, increase in amount of fatty acids to prevent more membrane fluidity
  • as temp. decreases, increase in unsaturated fatty acids to maintain membrane fluidity
59
Q

Lipopolysaccharides (LPS)

A
  • on gram (-) cells only
  • hair-like extensions
  • negatively charged
  • associated with OM only
  • highly immunogenic
  • easily pop out of OM due to fluidity
  • Lipid A in OM
  • core polysaccharides made of 7 carbon sugars middle part
  • O side chain made of 6 carbon sugars, part that sticks up highest
60
Q

Teichoic acid

A
  • on gram (+) cells
  • negatively charged
  • stick out from CW, CW anchors them
  • typically don’t find in high conc. outside of cells
  • don’t know function
61
Q

Fimbriae

A
  • short hair-like extensions from cell surface that play a role in adhesion
  • eq. some bacteria in gut, in aquatic systems, in mouth
62
Q

Pili

A
  • pilus (s)
  • longer extensions out from surface of cell
  • not sure of function
63
Q

Sex pilus

A
  • conjugation

- hollow tube extends from donor to recipient and transfers DNA

64
Q

Gas vacoules or vesicles

A
  • seen in aquatic species
  • used in flotation or movement within a water column
  • protein-bound structures that expand or contract to control bouyancy
65
Q

Storage polymers

A
  • coping mechanism some cells use to deal with nutrient deprivation
  • eg. carbon - glycogen and PHB
  • eg. polyphosphate granules
  • eg. elemental sulfur
  • eg. magnetite: responds to magnetic fields
66
Q

Glycocalyx

A
  • capsule, slime layer, exopolymer and exopolysaccharide
  • outtermost layer to cell
  • sticky due to sugar composition
  • provide high degree of chemical resistance but porus for nutrients
  • protects against dessication
  • resists UV damage
  • resists phagocytosis
67
Q

Prokaryotic spores

A
  • spores or endospores
  • highly resistant to temp., dessication, chemicals, etc.
  • form of survival (not reproduction), occurs in response to stress
  • sporulating cell becomes the spore
  • 1 cell becomes 1 spore

Microbiology (22 decks)

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