Three

Description

MICR222 Flashcards on Three, created by ruby.white94 on 13/10/2013.
ruby.white94
Flashcards by ruby.white94, updated more than 1 year ago
ruby.white94
Created by ruby.white94 almost 11 years ago
37
0

Resource summary

Question Answer
Oligotrophic Few nutrients
Allochthonous From environments other than where it has ended up
autochthonous Native to this habitat
What are aquifers? Water trapped under soil and above solid rock
What are some features of aquifers? Very oligotrophic usually very pure 1/3 NZ ground water high in nitrate
Why does river nutrients vary? Can be oligotrophic but varies Influx of tress,roots, leaves washed into river
Why are rivers so well oxygenated? Moving water
What is a microbial feature that helps them survive in rivers? Stalk production
what percentage of rivers are unsafe for swimming? 52%
When are lakes stratified? Summer and spring
What is the thermocline The point in a lake where the temp drops dramatically Also point where to epilimnion and hypolimnion meet
What occurs in the mud sediment of a lake? Methanogenesis, sulphate fermentation, anaerobic fermentation
What is produced in the mud sediment? H2S, CH4
What are the oxygen, H2S and temp like in the epilimnion, thermocline and hypolimnion? O2 in E is high (10mg/l) in H is low below 8mg/l in thermocline between the two H2S is up to 12 in H but not in E or thermocline Temp 20ish in E, 10-4 in thermocline after that 4 or below
What is the community in the epilimnion? Photosynthetic aerobes, phoic zone 6CO2 + 6H2O = C6H12O6 +6O2
What is the second from surface community in a lake Aaerobe and faculatative aerobes, oxic zone C6H12O6 + 6O2 =6CO2 + 6H2O
What are the four guilds of community three? Guild 1 = denitrifying bacteria and ferric iron-reducing bacteria Guild 2 = sulfate reducing bacteria and sulfur reducing bacteria Guild 3 = fermentative bacteria Guild 4 = methanogenesis and acetogens
Denitrifying bacteria and ferric iron reducing bacteria NO3- -> N2 Fe3+ --> Fe2+
Sulfate and sulphur reducing bacteria SO42- -> H2S S --> H2S
Methanogenesis and acetogens? CO2 --> CH4 CO2 --> acetate
What are the gradients in a lake? Light is high at top low at bottom energy yeild gets lower as you go deeper H2S gets lower as you go higher
Liebigs law of minimum States that the total biomass of an organism is dictated by the nutrient present in the lowest conc relative to the organisms requirements
Shelfords law of tolerance States that there are limits to environmental factors that below or above which a microbe can not grow regardless of the nutrients
Eutrophification Increase in nutrients usually C,N and P. Sewage leakage etc
What doe eutrophification lead to? An increase in oxygen decomposers and then a decrease in oxygen as it all gets used up Environment becomes anoxic Accumulation of toxic products by anaerobes
List the 6 adaptations microbes have to aquatic environments 1. small cells 2. Sheathed bacteria 3. pigament production 4. Motility 5. Magnetotatic bacteria 6. Utilisation of nutrients in low conc
Two types of motility handy in an aquatic environment Flagella Gas vacuoles
The advantage of magnetotactic bacteria Have magnetosomes, membranous vesicles with FeO4 and iron sulphate gregiate helps overcome thermal forces and orientate the cell
High affintiy enzymes Help uptake in oligotrophic environment
Halotolerant Can tolerate changes in salt content
Halophilic NaCl must be 2.5-4% Need high Na content to maintain high K content need for enzymes to work
How many atms of pressure increases every 10m of depth? 1
Barotolerant Can handle change in pressure up to 4000m deep
Barophilic Only live deeper than 4000m Enzymes only function at this pressure
Extremepiezophile like about 800atm pressure
Warm vent 6-23 degrees
Black smokers 350 degrees
what is the trophosome sponge tissue high in? Sulphur granules prokaryotic cells 10^9 per g/tissue
What goes in the bronchial plume and why is the plume red? CO2 and O2 from seawater H2S from hydrothermal vents Red because of haemoglobin
How does H2S normally harm the tube worm? It blocks O2 sites on the haemoglobin posions cytochrome c
How has the tube worm gotton around being posioned by H2S? Modified haemoglobin with capacity for O2 and H2S binding haemoglobin Modified cytochrome c
What are the benefits for both the tube worm and the bacteria? Bacteria are chemolithotrophic and get H2S Supplies host cells with organic molecules
Photobacterium are.. Chemolithotrophic
What is the advantage to fish of having bioluminescent bacteria? Attracts prey to fish
What do flashlight fish have to accomadate luminescent bacteria? An organ wit a membrane that can open and close revealing or concealing light
What enzyme and what substrates are needed for light emitting reaction? Enzyme luciferase long chain aldehyde compound (RCHO), oxygen and flavun mononucleotide (FMNH2)
What is the overall reaction for light emitting reaction? RCHO + FMNH2 + O2 ----> FMN + RCOOH + H2O and light! Luciferase ATP --> ADP
What are shipworms Mollusks, Teredo navalis
What do shipworms do? Get into and destroy wood, they have mutualistic bacteria to destroy cellulose
Teredinibacter Obligate marine bacteria that degrade celluose, found in shipworms Also fix nitrogen need nitrogenase and cellulase
What are algal blooms Increase in nutrients that leads to algal bloom, which can make harmful toxins
What did the saxitoxin of the NZ alexandrium minutum do? Blocks sodium channels enabling nerve impulses and killing animals Economic loss
Within 200m of water depth what is the temp like in the sea? Greatly variable depending on where you are
What is the temperature range for most deep water? 5 to -1.5 degrees
What is the freezing point of seawater? -2 due to salt
What is the pH of the sea 7.5
Why did romans cover there aqueducts? To stop algal growth (no UV) To keep it cool to stop leaves etc getting in
What lead to the start of water purification? John Snow linking cholera to water supply
What are sources of potable water? Ground water, aquifers, springs Surface water lakes, rivers and reservoirs Desalination of the sea
Catchment area Area of land around a water source
Why is it so important for catchment area to be clean? Determines the quality of water even after treament
What are some examples of natural pollution? Minerals and salts, animal and plant waste, dissolved gases, run off from bogs and slit, natural radioactivity and heavy metals
Human pollution examples Thermal, pathogenic microbes, organic matter, toxic compounds, eutrophification, detergents and radioactivity
What are the requirements for a clean catchment area? Don't want agriculture on this land low amount of N and P, no landfills, industry and limited human access
Sediementation and screening All solids settle and water is taken from the middle of the middle
Aeration Removes dissolved gases
chemical flocculation Aluminium potassium sulfate causes larger aggregates and air pressure causes flotation
Filtration Rapid or slow sand filter should remove protozoan cysts Or membrane filter 2-5um big should also remove cysts
Chlorination CL2 +H2O ---> Cl- H+ and HOCl HOCL is a strong oxidiser kills bacteria
residual concentration Concentration that must be present at the furthest point from the treatment plant Cl - 0.2mg/l F - 0.85mg/l
UV treatment 245nm Disrupts DNA and RNA thin stream flows past bulbs
Max values of E.coli and oocysts in water E.coli <1/100ml oocysts <1/100L
BOD Biological oxygen demand Measures the demand for oxygen by bacteria during degradation of organic matter and indicate conc of organic compounds in water
What is the con of testing for BOD Tends to underestimate
COD Chemical oxygen demand Potassium dichromate oxidises organic compouns to CO2 and H2O
Advantages and disadvantages of COD Advantage is - rapid 3hrs Disadvantage can't distinguish between biodegradable portion and nonbiodegradable Overestimates but regular testing shows trends
Why does BOD tend to underestimate? It doesn't measure all biodegradble portion
How is measuring BOD carried out? Sample put in dark at 20 degrees and measured after 5 days
Why do we use a bacterial indicator instead of just testing for pathogens? Wide variety of species and genra, have to do many cultures etc, takes too long, could be present in very few numbers but enough to cause disease
What is an ideal organism? Bacterial inhibitor of the large intestine Non pathogen easy to identify present in large numbers survives long in water but doesn't reproduce
What is the best indicator organism? A coliform, we use E.coli because it isn' found in soil
features of E.coli Gram -ve rod Lactose fermentor with gas within 48hrs at 35 degrees
ONPG test Coliform produces p galactosidase beta which acts on ONPG and turns it yellow
MUG test E.coli produces beta-glucuronidase which acts on MUG and turns it fluroscent blue
What is the colihert test? A commerical test add reagent to sample and incubate for 24hrs read it.
Membrane filtration test Trap microbes of filter and put in on a slective and differential agar
Disadvantages of using a indicator bacteria Bacteriophage, doesn't detect algae, E.coli might rapidly die off in some waters, viable but non culturable E.coli gives false negatives, clusting could give false negatives and positives
Rhizophere The zone of root influence, extends 5mm from root
Rhizoplane Root surface
Root colinization bacteria grow as microcolonies over 5% of the root
Populations around the root are... Usually 20-100 times more than in the surrounding soil
Show full summary Hide full summary

Similar

REDUCE, REUSE, RECYCLE
Oksana Bogdan
Anthropology Final-- Part 3-4
Heather McCord
Research Methods III
Ben Armstrong
Checks and Balances
Megan Jordan
Test
c.duncan
ES-61 - Generate Shock Stimulus
William Farrer
Latin Stems
Courtney Borland
vocab list 3
natmar525
gfdgdfg
Mats Fjellner
multiple choice
qamra alotibi
3 Little pigs outdoor
clairelunt1