ecology, biogeochemistry, industrial micro

Question 1

doubling time of microbes

Answer 1

30 min

-> fast evolution, diversification.

Question 2

physical environment

Answer 2

influences interactions of microorganisms with each other

Question 3

microenvironment

Answer 3

specific physical location of microorganism = can be interface btw 2 environments
- impacted by fluxes of nutrients + diffusion rates of waste products

Question 4

Niche

Answer 4

function of organism in complex system
- adaptation to particular location

Question 5

ppopulations

Answer 5

consist of cells of same species

Question 6

guilds

Answer 6

one or more metabolically related population

= same function

Question 7

abiotic constraints

Answer 7

moisture
temp
pH
redox potential
salinity
light
pressure

Question 8

tolerance limits

Answer 8

optimal range
zone of physiological stress (low habitation)
zone of intolerance ( species absent)

Question 9

bacterial species?

Answer 9

hard to define because species based on interbreeding + fertile offspring. but prokaryotes reproduce clonally, not sexually.

Question 10

using polyphasic taxonomy

Answer 10

to classify species

- use combinations of genotypic AND phenotypic markers

Question 11

what is exclusionary principle?

Answer 11

each niche is occupied by only one species

Question 12

microbial ecology

Answer 12

environmental samples continue to reveal novel bacteria from phylum to species levels

Question 13

diversity in bacteria

Answer 13

less in physiology than in genomes.

metabolism restricted to periodic table

Question 14

species richness
species evenness:
species composition:
species dominance:

Answer 14

R: total number of species
E: relative abundance of species
C: which species are present
D: the most abundant species

Question 15

potential niche

Answer 15

the niche that the organism could theoretically occupy

Question 16

realized niche:

Answer 16

niche that the organism actually occupies

Question 17

why are potential + realized niche not the same

Answer 17

competitive exclusion = only one species occupies a niche, but resource partitioning = niche can be divided to form narrower niche

functional redundancy = same potential niche, diff realized niche - organisms lost when outcompeted unique

Question 18

negative and positive interactions btw growth rate + popln density

Answer 18

growth rate increases as population density increases = tapers at a point = positive

negative: popln increases, growth rate decreases due to competition

Question 19

overall population density considering both +/- interactions

Answer 19

low popln density, low growth rate, dont have enough individuals for +interaction.

high density = low growth rate. more interactions of negative interactions. intermediate = highest growth rate.

Question 20

resistance vs resilience

Answer 20

resistance: disturbance has little to no effect. survival.
resilience: after disturbance, recovery is high.

Question 21

what are biofilms

Answer 21

organized microbial systems attached to surfaces

• enclosed by adhesive extracellular matrix
• creates multiple microenvironments

Question 22

benefits of biofilms

Answer 22

intercell communication, easy access to resources as water + nutrients float by.

Question 23

how actiera attach?

Answer 23

1 pilliattach = body turns off most genes

2. make polysaccharides + other things to attach to other bacteria + surface.

Question 24

microbial mats

Answer 24

thick biofilms have macroscopic dimensions

• layered, each layer is a guild
• aquatic environments: when extreme, separate into layers.

Question 25

soil habitat

Answer 25

most microbes in microcolonies - attach to soil particles - most grow near plant roots due to high level of nutrients - water limitation is greatest stress (either too much or too little)

Question 26

chemical distribution and biosignatures.

Answer 26

- through layers of water, different amounts of elements = diff organisms at each level, once one chemical is used move to next one.

Question 27

two characteristics of chemical dstn and biosignatures?

Answer 27

1. amount of energy available from chemical reactions | 2. chemical constraints

Question 28

lake michigan chemical dstn/biosignature

Answer 28

- high O2 at top of sediment btw water/sediment interface = aerobic respiration + organic matter. O2 depletes, No3- used. fixed so used quickly. as NO3- fixed, NO2- increases sulfate increase once NO2- decreases. metals: better e- acceptors. needs to dissolve to be used - tricky to do methane + CO2 in system = aerobic, fermenters, methanogens. ammonia in deeper waters = degrade organic matter.

Question 29

black sea chemical dstn/biosignature

Answer 29

``` aerobic @O2 Nitrogen-fixers @ high NO3- Mn/Fe reducing bacteria where high MN++ and FE++ NH4+ = ammonia oxidizers sulfate = sulfate oxidizers. ```

Question 30

biogeochemical cyclins

Answer 30

biological + chemical processes -ox-redox reactions that change chemical and physical characteristic of nutrients = all nutrient cycles are linked

Question 31

carbon cycle

Answer 31

lin O2 and C. - photosynthesis produces O2 and removes CO2 - respiration removes O2 (aerobic) and produces CO2 (re-mineralizes) - anaerobic resp + fermentation = diff form of C methanotrophy from fermentation = oxidized to CO2.

Question 32

aerobic carbon use

Answer 32

organic C + O2 => CO2 of other forms of oxidized products ( H2O, NO3-) organic C = reduce to oxidize C H2, NH4, H2S, CO2 = chemoheterotrophs chemo autotrophs use reduced compounds to oxidize them

Question 33

anaerobic carbon use

Answer 33

organic matter - use other oxidant, to oxidize organic matter to CO2. methanogens use CO2 anaerobically to produce methane

Question 34

what is syntrophy

Answer 34

"eating together" | - all dependent on each other. one produces food for the next.

Question 35

3 strains of methanobacterium omelianskii

Answer 35

S = unfavourable reaction energetically MoH - favourable + spontaneous reaction -co-culture of the 2: net reaction is favourable. so S can grow. S is obligate syntrobe bc interspecies H transfer.

Question 36

link between N cycle + C cycle = photosynthesis

Answer 36

high Organic C = more N2 fixation. less OC = less N2 fixation - negative feedback from N2. high nitrate.ammonia = drive photosynthesis for more fixed carbon

Question 37

microbial N cycle

Answer 37

Nitrogen fixation: N2 -> NH3 -> NH2OH: nitrification-> NO2 -> NO : denitrification -> N2) -> N2 oxidation: NH2OH -> NO Anammox NO2 -> NH3 assimilation: No2 -> N2 or NH3 -> N2

Question 38

Reactive Nitrogen

Answer 38

``` NO: vasodilator, free radical + destroy ozone layer N2O: greenhouse gas NO2: potent carcinogen NO3-: major water pollutant NO2: smog ```

Question 39

N fixation

Answer 39

reduce N2 -> ammonia prokaryotes only - mass expenditure of energy, e-, and anaerobic enviro. - aerobes + anaerobes

Question 40

nitrification process

Answer 40

aerobic ammonia oxidizers (reverse electron flow) nitrite oxidizers =N2O

Question 41

anammox process

Answer 41

anaerobic ammonia oxidation - produce N2 from ammonia + nitrite - in membrane-bound organelle, intermediate it super reactive.

Question 42

denitrification

Answer 42

anaerobic heterotrophic (Ocarb + N-oxide (oxidant) - lots of bacteria do this release N2O to atmosphere

Question 43

iron and manganese processes

Answer 43

two oxidation states each - reduction of them in anoxic enviro = mobilize metal into soluble, oxidized form. - lowpH, common in coal-mining, results in acid mine drainage

Question 44

meta cycle

Answer 44

oxidized form can percipitate out + sink to bottom. -can utilize metal a lot before precipitates out. not re-oxidized easily. ocean marine system uses sulfate to interact with metal + percipitatte itout

Question 45

what is acid mine drainage

Answer 45

dig mine site, pyrite precipitates + turns to sediment. when aerosolized, converted to Fe3+ = sulfide oxidized to sulfate (Hso4- = acidic)