Brainscape's Knowledge GenomeTM

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


See full index

Bio 240 > Topic 6: > Flashcards

Topic 6: Flashcards

1
Q

PHLOGENETIC DIVERSITY?

A

Result of 4 billion years of evolution

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

Metabolic diversity

A

if there is a niche to exploit, micro-organisms have adapted to exploit it

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

Catabolism

A

Releases energy
breaking things down

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

anabolism

A

consumes energy
makes things, nutrients are needed

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

Macronutrients

A

Required by all cells to build macromolecules
C N P S O

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

Micronutrients

A

needed by some cells
Fe Cu Na Mg Mn
Pathogens really know Fe

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

Fundementals of nutrition NAMES

A

Energy source:
Photo/chemo
Electron source:
organo/litho
Carbon Source:
hetero/auto

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

What are humans? E.coli, Pathogens, anything in bio240L

A

Chemoorganoheterotrophs

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

What are cyanobacteria named?

A

Photolithoautotrophs

get e- from water
eat co2 but electrons arent from there

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

What is only found in prokaryotes?

A

Chemolithotrophs

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

Phototrophs are oxygenic or anoxygenic?

A

Yes!

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

Carbon is a major requirement for all organisms. Why?

A

-energy storage and manipulation
-structural purposes

Autotrophs fix co2 into C

Heterotrophs
use organic molecules made by autotrophs

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

What is growth rate dependent on?

A

Nutrient concentration. The higher the concentration, the faster the growth rate

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

Nitrogen is aquirred how?

A

Ammonia into glutamine or glutamate
-critical for amino acids and nucleic acid construction

Nitrogen is needed in a useable form and this is the useable form

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

Why do we need to limit growth?

A

Uncontrolled growth means that technically , under ideal circumstances, something like n ecoli can “grow to the size of the earth”

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

Obligate Aerobe

A

require oxygen

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

microaerophiles

A

grow best in low oxygen levels

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

obligate anaerobes

A

cannot grow when o2 is present

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

aerotolerant aerobes

A

are not harmed by o2 but dont use it

20
Q

faculatative anaerobes

A

can grow without oxygen but grow better when it is present

21
Q

Toxic oxygen species

A

impact of o2 respiration on a cell depends on a cells available defenses

O2-, OH-, H2O2, are all oxidizers that oxidate anything that it can find
cell needs to have ways to prevent this so that it doesnt have its lipids, proteins or dna oxidize. Those that are able to do this can live in oxygen environments
pg 23 on notes

22
Q

Catalase Test

A

Determine whether species can handle o2 or not

Catalase takes peroxide and converts it to oxygen
-means aerobe cause can handle respiring oxygen
h2o2 + h2o2 -> 2H20 + O2

23
Q

pH names of microbes

A

Acidophile: 5.6 and lower
Neutrophile: 6-8
Alkalophiles: 8-14

24
Q

What can decrease water activity? Aw

A

interaction with solutes decrease Aw

pure h20=1.0
seawater:0.98

25
Q

Xerophiles

A

Love low water activity

26
Q

Temperature names of microbes

A

Temp affects membrane fluiditiy, enzyme function and macromolecule structure

Psychrophiles: -20-10
Mesophiles: 10-60
Thermophiles: 60-80
Hyperthermophiles: 80-120

Optimum temp is the temo that enzymatic reactions occur at max
Higher than this leads to protein denaturing
lower: membrane gelling so transport process so slow that growth cant occur

27
Q

Psychophiles

A

Min : <0
optimum: 15
Max: 20

-Unsaturated fatting acids allow for colder temp stability cuz they stay fluid even at low temps so more of this than in mesophiles

  • found in oceans, etc
28
Q

Psychotolerance

A

0-4 degrees
optimum: 20-40
capable of low temp growth

ex: ecoli
found in soil, house, etc

29
Q

Hyperthermophiles

A

Supervolcano, boiling springs that are heated above boiling point

all temps above 50-60
soil in midsummer
compose
hotspring
deep sea hydrothermal vent
hot water heaters

30
Q

Molecular adaptations for high temps

A

-increased A A bonds produce heat-resistant folds
-ionic bonds between acidic and basic residues
-certain solutions help stabilize: di-inostol phosphate and diglycerol phosphate

-saturated fatty in bacteria
-phospholipid monolauyer in archaea more thermotolerant than bilahyer (two head)

31
Q

Media Types

A

Complex Media
-unknown composition
(IF SAYS YEAST EXTRACT, PEPTONE, TRYPTONONE)
Defined media
-known composition
(GLUCOSE, NACL, ETC)

32
Q

Specialized media names / types

A

Selective media
-allows for isolation of a specific microbe/s due to specific properties

Differential media:
-allows different microbes to be identified based on visual reactions with medium
ie, colour

Enriched media
-used to increase a population of microbes with a certain property

33
Q

How to obtain pure culture?

A

On Solid medium easier since cells are held in place and can be isolated

1) Streak plate method
2)spread plate method (glass hockey stick)
3) pour plate method (liquid), not all organisms want to be at this temp

34
Q

How to quantify microbes

A

1) Direct Count (Petroff hauser chamber, known amount put on to slide with grid and coverslip, cells counted with viable microscope (CANT DIFFERENTIATE BETWEEN DEAD AND ALIE CELLS)
2) Viable cell Counts (Serial dilutions and CFU’s, cultures diulted in series of tubes, and plates (1 in 10, 1 in 100), colonies counted after incubation
3) Turbidity measurements: spectrometer sends light through culture, light absorbance dictates density of cells, less transmittance, more growth

35
Q

Colony forming units

A

Colony forming units per mL of culture, calculated by multiplying the nuber of colonies by INVERSE of dilution factor (1/1x10^-5)

36
Q

Microbial Growth Curve

A

Lag Phase: preparing for steady growth
Exponential phase: Replicating and growing at a steady and constant exponential rate
Stationary phase: death rate equal to growth rate or replication Halted
Death Phase: nutrients depleted, waste lebels high, so cells are dying at exponential rate

37
Q

Generation time

A

Time it takes to double the population in exponential phase
rise/run

38
Q

Growth rate

A

numner of generations per unit time (run/rise)

39
Q

Growth yield

A

max population density and or amount of cellular material produced by culture

40
Q

What is continous culture used for?

A

-used to keep micro in exponential growth phase, to harvest one of their producets (kept in limited biut continous flow of nutrients)

Chemostat flows in fresh medium and takes out old

41
Q

Four ways to control growth (kill microbes, sterilize something)

A

1) Filteration: Use different pore size to allow different things in or keep certain things out
0.2 common for sterilization
3 filter types:depth folters (removes big particles first cuz ti doesnt clog)
Conventional membrane filter: used for routine sterilization
Nucleopore filters: has consistent pore size cuz radiation made the pores, used for microcospy

2) Temperature
heat denautres it, 100 degrees kills most
Sterilization method; Autoclave used: adds pressure, which keeps fluid from evaporating at high temps, brings temp to 121 without boiling it. Effective on endospores and hyperthermophiles can get it to high heat

TO be sterilized, SAMPLE temp must be at 121 for 15 mins ( not autoclave time, but temp of organism)

Pasteurization
NOT FOR STERILIZATION
-reduces microbial long (90-99%)
HTST: 72 degrees 15 seconds
UHL: 1 second 135 degrees
ESL: filter, then pasteur, for increasing shelf

Freezing better for long term preservation cuz stops biochem reactions

3) Electrochemical radiation
SANITIZATION NOT STERILIZSTION cuz controls microbial grouth on non-living surfaces
UV radiation of 260-280nm
can damage dna by forming THYMINE DIMERES (cuases frameshift mutations in proteins)
Ionization radiation is used: protein damage, dna damage, hydroxides formed,free e-, limited to industries cuz cosstly and hazardous

4) Chemicals
Antimicrobial agents: target bacteria, fungi, algi, uiricide
-can be non-selective (kills everything, affrct sulfhydryl group which all things have
-can be selective (antibiotics affecting euk ribosomes, or penecillin)
useful for disease

42
Q

Bacteriostatic, cidal and lytic

A

Bacteriostatic: growth inhibitory (tetracylin, ampicilin
Bacteriocidal: kills cells
Bacteriolytic: lysis cells ( penicillin)

43
Q

Commonly used disinfectants

A

Ethanol: Membranes
Triclosan: Membrane (phenolic)
Benzalkonium chloride: Membrane
Sodium hypochlorite: oxidizing agent
Glutaraldehyde: crosslinks proteins

44
Q

Antibiotics

A

antimicrobial agents produced by microbes
-work by binding to proteins or other cellular organelles to disrupt function

Broad spectrum: Tetracycline (both gram neg and gram pos, inhibit protein synthesis)
Narrow spectrum: Pennicillin (inhibit cell wall synthesis of gram pos bacteria)
Polymyxin B ( Disruption of outer membrane (gram neg)

45
Q

Decimal reduction time

A

Time required to kill 90% of the target organism under specific conditions

DT is at 300 grays, If we start with 1,000,000 org in culture , how many do we expect to see after exposed to 900 grays?

1000 (take off zeros based on how many times 300 goes into 900)

46
Q

Lactam ring

A

bacterilytic

Bio 240 (7 decks)

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