Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Microbiology > Lecture > Flashcards

Lecture Flashcards

(68 cards)

Start Studying
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
What are the 3 domains of life?
1. Bacteria 2. Archaea 3. Eucarya
25
Conserved regions in the 16s rRNA gene?
- unspecific applications | - same among all prok.
26
Variable regions in the 16s rRNA gene?
- group or species-specific applications | - species-specific, used to identify
27
What do changes in sequences of conserved regions result in?
Loss of function of 16s rRNA gene (translation)
28
What do changes in sequences of variable regions result in?
- Not necessarily loss of function but may lead to misidentification of organism.
29
Which categories are applied in naming in microbiology?
Class, Genus, Species
30
What groups of microorganisms are included in the domains?
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
Differences between prok. and euk.: nucleus
euk. only | nucleoid in prok.- chromosomes but no membrane
32
Differences between prok. and euk.: membrane-bound organelles
euk. only
33
Differences between prok. and euk.: number of chromosomes
- euk. have more than 2 | - prok. have one
34
Differences between prok. and euk.: cell membrane
both euk. and prok.
35
Differences between prok. and euk.: cell walls
- some euk. have | - all prok. have
36
Differences between prok. and euk.: size
- euk. larger
37
Viruses
- not living (?) - no metabolism - reproduction via host cell only not thought to communicate with their environment (adaptation and evolution?)
38
Algae
- 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
Protozoa
- euk. - pathogenic/parasitic - have no cell walls - divided into groups based on motility
40
Groups protozoans are divided into
Based on motility - amoeba - falgellates - ciliates - sporozoites
41
amoeba
- euk. - protozoa - amorphous (no shape) - motility via cytoplasmic streaming - eg. Entamoeba histolytica --> causes dysentary
42
Flagellates
- 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
ciliates
- 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
Sporozoite
- euk. - protozoan - spreads between hosts via cysts (spores) - obligate intracellular parasite - eg. Plasmodium spp. --> causes malaria; spread by mosquito (Anopheles spp.)
45
Fungi
- 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
Yeasts
- 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
Molds
- 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
Mushrooms
- 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
Slime Molds
- 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
What are the 3 basic morphologies within prokaryotes?
1. coccus (s); cocci (pl) 2. bacillus (s); bacilli (pl) 3. spirillium (s); spirilli (pl)
51
Bacteria represent _______, while archea represent _________.
"common" prokaryote (eg. Escherichia coli); extreme prokaryote, eg. extremes in temp., pH, salt conc., contaminated environments (eg. Thermus aquatreus)
52
Bacteria and archea have similar ________ but can have different
structures; chemical compositions
53
Cell wall of bacteria are comprised of __________, while cell wall of archea are comprised of __________.
peptidoglycan; pseudomurein
54
Cell wall
- 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
Composition of bacterial cell wall
- 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
Outer membrane
- phospholipid bilayer - fluid mosaic model - selective because of transport proteins - heavily populated by porins (open, non-selective channels) --> make OM less selective
57
Cell membrane
- 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
Fluid mosaic model
- 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
Lipopolysaccharides (LPS)
- 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
Teichoic acid
- 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
Fimbriae
- short hair-like extensions from cell surface that play a role in adhesion - eq. some bacteria in gut, in aquatic systems, in mouth
62
Pili
- pilus (s) - longer extensions out from surface of cell - not sure of function
63
Sex pilus
- conjugation | - hollow tube extends from donor to recipient and transfers DNA
64
Gas vacoules or vesicles
- seen in aquatic species - used in flotation or movement within a water column - protein-bound structures that expand or contract to control bouyancy
65
Storage polymers
- 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
Glycocalyx
- 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
Prokaryotic spores
- 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.
© 2025 Bold Learning Solutions. Terms and Conditions