MICRB 265 > Week 2 > Flashcards

Week 2 Flashcards

(64 cards)

Study These Flashcards
1
Q

Till the 1800s, people thought that the cause of disease was _____

A

bad air

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

Germ theory of disease developed by _____ states that ______

A

-Louis Pasteur and many others
-many diseases are caused by specific bacteria

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

Germ theory was proposed in ____ but not accepted until ______

A

-mid 16th century
-19th century

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

Spontaneous Generation was the idea that ______

A

organisms were spontaneously created from inorganic materials

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

Spontaneous Generation was disproven in ___ + method

A

-1864
1.liquid in flask with curved neck heated = sterile
2. liquid remain sterile
3. sterile liquid tipped to enter neck = liquid spoils

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

Spontaneous Generation led to the invention of ______ which is _____

A

-pasteurization
-heating liquids for a short period of time to kill pathogens

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

Koch’s postulates (__) established a _____

A

-1890
-causal link between the organism and disease (ie. this organism caused this disease)

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

Koch’s original postulates

A
  1. The pathogen must be present in all cases of the disease and absent from healthy animals
  2. Pathogen must be grown in pure culture
  3. Cells from pure culture of suspected pathogen must cause disease in healthy animal
  4. Pathogen must be reisolated from animal infected
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Issues with Koch’s postulates

A
  1. things that viruses that cause disease but don’t fulfill postulates
  2. asymptomatic carriers
  3. can’t grow organisms because of strict nutritional/environmental needs
  4. need specific healthy organisms (ex. humans- ethics)
  5. people with strong immune systems may fight off infection
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Koch’s postulates was used to identify ____

A

tuberculosis

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

Modified Koch’s postulates by Fredricks and Relman are better because ______

A
  1. it accounts for viruses (only need nucleic acid of pathogen to be present in most cases)
  2. acknowledge asymptomatic carriers have NA of pathogen
  3. disease resolution is when NA is less/no longer present
  4. severity of disease - number of NA
  5. acknowledge that pathogen may localize in one area only
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Life -> ______ —> ______

A

-domain
-kingdom

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

Kingdom –> ______ etc.

A

-phylum (please)
-class (come)
-order (over)
-family (for)
-genus (good)
-species (sushi)

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

How do we get phylogenies? why?

A

-DNA sequence of 16S rRNA
-ribosomal nucleic acid is stable over time and is vertically transmitted (from parents)

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

firmicutes is a phylum of bacteria + facts

A

mostly gram positive, many produce endospores and it includes clostridia and bacilli

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

anctinomyceotota is a phylum of bacteria + facts

A

-gram positive, contribute to decomposition of organic matter and includes streptomycetes and myobacteria

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

bacteroidetes is a phylum of bacteria + facts

A

gram negative, major vertebrate colonzier, digusts complex carbohydrates, modulate immune host responses, includes bacteroides

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

proteobacteria is a phylum of bacteria + facts

A

gram negative, very diverse, numerous pathogens, includes escherichia and yersinia

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

Who is Robert Hooke?

A

-wrote the first book dedicated to microscopic observations in 1665 (mostly fruiting structures of molds)

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

Who is Antoni van Leeuwenhoek?

A

-discovered bacteria in 1676

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

most common microscopes

A

light microscope

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

magnification (def.)

A

degree to which image is enlarged

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

resolution (def.)

A

ability to distinguish adjacent objects and distinct and separate

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

resolution is affected by wavelength; longer wavelength = ____

A

lower resolution

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
resolution limit for light microscopy is ___
0.2 um (bigger than 0.2 um can distinguish)
26
contrast (def.)
ability to see an object as distinct from its surroundings
27
Light microscopes are used for _____ (microscopy types)
* Bright field microscopy * Phase contrast microscopy * Differential interference contrast * Fluorescence/Confocal microscopy
28
Electron microscopes are used for _____ (microscopy types)
* Scanning electron microscopy * Transmission electron microscopy
29
problems with bright field microscopy
* can be hard to see * move in and out of fields of view with fluid dynamics * not a lot of useful information
30
contrast with bright field microscopy can be improved with _____
stains
31
Gram stain procedure
1. crystal violet (purple) 2. iodine (causes crystal violet to form crystals) 3. alcohol (decolourize by solubilizing crystals) gram +: crystals can't get out of thick peptidoglycan gram - : crystals can get out of thin peptidoglycan 4. safranin colours everything pink gram + : purple gram - : pink
32
phase contrast microscopy has _____
condenser than changes the relative wavelength from sample giving good contrast between cells (darker than background)
33
phase contrast microscopy is used to image ______
cell that are alive and motility
34
How fluorescence microscopy works?
* Certain molecules can absorb photons: * This causes electrons to become excited and move into a higher energy state * When the electrons relax, they emit a photon * This photon is called fluorescence
35
Confocal fluorescence microscopy is better because _______
you only see one plane of focus and then take multiple images to form a 3D image
36
Electron microcopy uses ______
electrons instead of light, which have a shorter wavelength (higher resolution) than photons but larger than photons
37
electrons being larger than photons means that ______
they cannot penetrate large objects so it's good for imaging proteins (very small) but not cells
38
SEM sees ____
outside of cell, 3D imaging
39
TEM sees _____
inside the cell by taking images of very thin samples of cells cut with diamond blade
40
nucleoid body =
genome + proteins
41
genome organization with proteins allows genome to ____
fit into small cells
42
what are plasmids?
* Small, circular DNA (1000-100,000 bp) * Contain origin of replication (replicate independently of genome) * Can have multiple copies per cell * Serve many different functions: antibiotic resistance, transfer of DNA between cells (conjugation), virulence genes
43
Ribosomes in prokaryotes parts
50S (23S & 5S rRNA) + 30S (from 16S rRNA)= 70S
44
FtsZ is a _____ of bacterial cytoskeleton that does what? found in?
-tubulin homolog -cell division -most bacteria and archaea
45
TubZ is a _____ of bacterial cytoskeleton that does what? found in?
-tubulin homolog -plasmid segregation -found in Bacillus species
46
MamK is a _____ of bacterial cytoskeleton that does what? found in?
-actin homolog -positions magnetosomes -magnetotatic bacteria
47
magnetosomes allow bacteria to _____
undergo magnetotaxis (the process of migrating along earth's magnetic field)
48
MreB is a _____ of bacterial cytoskeleton that does what? found in?
-actin homolog -cell shape (spiral pattern organization in the cell) -found in most rod-shaped bacteria
49
CreS is a _____ of bacterial cytoskeleton that does what? found in?
-IF homolog -makes rods curved -found in caulobacter crescentus
50
MinD is _____ of bacterial cytoskeleton that does what? found in?
-unique to bacteria -prevents FtsZ from polymerizing at poles (moves it to the middle) -most species
51
What are inclusions?
* Intracellular bodies (no membrane)containing granules of organic or inorganic materials * Frequently contain enzymes * Involved in the storage of nutrients, metabolites, etc. * Glucose as glycogen * Carbon as poly-β-hydroxybutyrate * Polyphosphate as Volutin * Amino acids as Cyanophycin granules - sulfur and phosphate
52
what is carboxysome?
-Microcompartment - Protein shell -Sequesters carbon fixing enzymes Carbonic anhydrase and RuBisCo
53
Carbonic anhydrase does what?
coverts carbonic acid into carbon dioxide and water
54
RuBisCo does what?
CO2 + ribulose-1,5-bisphosphate → 3-phosphoglycerate
55
what are gas vesicles?
* Also a microcompartment * Long, narrow gas-filled structures * Buoyancy of aquatic organisms like cyanobacteria
56
what are magnetosomes?
* Magnetic iron oxides * Allows bacteria to move along Earth’s magnetic field lines * Membrane-enclosed
57
what are endospores?
-like seeds (part of lifecycle but not reproductive) * Produced when conditions are stressful within cell : Nutrient limiting, extreme heat, chemical exposure, radiation, desiccation (drying) * Dormant (highly dehydrated) * Non-reproductive * Very stable and resistant to desiccation, chemicals, antibiotics
58
endospores is only produced by ______
clostridia and bacilli (part of firmicutes)
59
types of endospores
-terminal endospores -subterminal endospores -central endospores
60
endospore --> _____
vegetative cell
61
sporulation (def.)
the process of cellular differentiation that creates endospore
62
maturation of endospores involves _____
dehydration of spore, Ca2+ uptake, SASPS, dipliocolonic acid then mother cell lysis
63
Escherichia coli is type of bacteria?
-Gram negative facultative anaerobe from γProteobacteria with peritrious flagella
64
E.coli is model organism because ____
* easy to grow * easy to manipulate * amenable to analytical techniques * fully sequenced genome
MICRB 265
flashcards
Decks in class (12)
# Cards
Brainscape helps you reach your goals faster, through stronger study habits.
© 2026 Bold Learning Solutions. Terms and Conditions