Exam Results: 09/25/2013 Please do NOT start changing your water yet!

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Exam Results: 09/25/2013 Please do NOT start changing your water yet!

Transcript of Exam Results: 09/25/2013 Please do NOT start changing your water yet!

Page 1: Exam Results: 09/25/2013 Please do NOT start changing your water yet!

Exam Results: 09/25/2013

Please do NOT start changing your water yet!

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Exam Results: 09/25/2013

3rd Period: 87.08 % Average 5th Period: 89.42% Average

4 Grades Over 100% 7 Grades Over 100%Highest Grade: 105 Highest Grade: 1051 Failure 1 Failure

6th Period: 83.10% Average

5 Grades over 100%Highest Grade: 1094 Failures

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Most-Missed questions

While you are fishing in the Atlantic Ocean you catch a fish with

HUGE eyes in comparison to the rest of its body. You accidentally

drop it on the deck of your boat and it intentionally flops into the

shadows before flopping back into the water. This fish most likely

came from the:

a) Epipelagic

b) Mesopelagic

c) Bathypelagic

d) Abyssopelagic

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Most-Missed questions

pH is the measure of

a) Hydronium

b) Hydroxide

c) Water

d) Total Ammonia and Nitrogen

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Most-Missed questions

Which of the following locations is at the lowest latitude:

a) The Arctic

b) New England

c) The Equator

d) The Antarctic

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Most-Missed questions

Most aquatic organisms live in the ____________.

a) Epipelagic

b) Benthic

c) Benthopelagic

d) Abyssopelagic

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All hands on deck water change & tank cleaning:1. Check all your tank chemistry

2. Change your filters:

1. Unplug your filter

2. If you have a canister filter, turn the valves at the end of the hoses 90 degrees into the “off” position

3. Remove your entire filter and take it to a sink

4. Dump the contents of your filter into the sink

5. Rinse out the inside of the filter with lots of water (Do not use soap)

6. Put your old filters pads in a bucket outside

7. Add new filter pads of the appropriate size, place the filter back onto your tank and fill with water.

8. Plug the filter back in and make sure water is flowing

3. Change 25% of your water or more if the filter belches out nastiness into your water

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Bellwork: 10/01/20131. What percent of water on the planet is freshwater?

2. What are the categories and percentages of the different forms of freshwater? Where would you find each?

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Bellwork: 09/30/2013

1) 6-Weeks Tank data is due to [email protected] by Friday.

2) Expectations for this data:

a) Excel Spreadsheet

b) Data for each day should be present, including a general evaluation of

the health of your tank.

c) Proportional Graphs need to be made for each chemical test.

d) Each Chart needs to be labeled & contain units (ppm)

e) Your tank number & all members of your group must be at the top of the

excel file.

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Bellwork: 09/28/2012

1) What is a buffer? Why are buffers important for the function of aquatic

systems?

2) If an aquatic system has a high concentration of bicarbonate, what will the pH

of that system be? Is this within the ideal range for aquatic organisms?

3) What role does limestone/other similar minerals play in the carbonate cycle?

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Bellwork: 10/02/2013

In the first 30 minutes of class you must complete the following:Change 10% to 25% of your tank’s water depending on how turbid your water appears. Scrub algae from the glass & the filter intakesMake sure to refill your tank to the top binding of the tankTurn in a copy of the following to Mr. Young & keep a copy for yourself:

Freshwater tanks: DO, nitrate, nitrite, ammonia, pH, temperature, Saltwater tanks: DO, nitrate, nitrite, ammonia, pH, temperature, water hardness

(kH), calcium, phosphateClean out the test tubes once you are finished!Leave the lids with the color indicator charts on the front desk!Once you are finished, or if you are not helping your group with your tank, continue to work on your microscope investigation.

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Instructions: Classroom Samples & Prepared Slides

**In groups of THREE OR LESS!

1.You will sketch each of the following as well as record the magnification that you think is ideal for observing this organism.2.Each sketch must be signed off by Mr. Young and this must be done while you have the specimen in focus!3.Using complete sentences (-10), write where each organism is most likely to be found.

1. Mixed Green Algae 9. Ascaris (Cross-Section)

2. Cyclops 10. Diatoms

3. Volvox 11. Amoeba

4. Euglena 12. Scale Types – 4 sketches

5. Spirogyra 13. Zooplex Wet Slide

6. Planaria 14. Phytoplex Wet Slide

7. Planaria Combo 15 – 20: A – F Depth Slides

8. Hydra (Depth does not need to be initialed)

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Instructions: Classroom Samples

**In groups of THREE OR LESS!

1. Get a microscope, plastic slide, plastic pipette. Don’t use your water sample yet.2.Collect a sample from any tank within the classroom. You will need to collect two from freshwater tanks & two from salt water tanks.3.Make sure to note the tank number from which you got your sample as well as where in the tank it was found (sand, rocks, algae colony, etc.). 4.Place one or two drops from your water sample onto the slide & use the lower two objectives of the microscope to find any large & mobile organisms in the sample. Draw a detailed picture of the organism you find & describe its movement. Mr. Young must sign off on each sample!

5.From what you observed, which of the previously mentioned organisms does your sample most resemble? Describe why you think this.

6.Rinse off the slide and repeat the above steps with different organisms.

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Instructions: Classroom Samples – Analysis Questions

1. Diatoms are the most commonly found specimen in this classroom. What does this tell you about the adaptability, evolution, and niche of these organisms?

2. Concerning the organisms that were taken from the sand/gravel/surface of rocks, etc: Which of these organisms are benthic, nektonic, or planktonic? How do you know this?

3. Look up the approximate pH for the following: bleach, liquid plumber, battery acid, ammonia, DEET, motor oil.

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Bellwork: 10/01/2012

1) How is a salt formed?

2) Define Alkalinity:

3) Review Expectations for cumulative data

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Bellwork: Drinking Water Quality

Source Treatment Distribution What do consumers care about?

How can that be protect and provided?

What are the most important chemical parameters?

HOMEWORK: Bring a sample of outdoor water. Examples: water in a horse trough, creek, ditch, puddle in a yard. Your sample needs to be at least 4 fluid ounces.

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Bellwork: 10/02/2012

1) What is the difference in species abundance & species richness? Give an example of each.

2) When considering microbial biology, what is a guild?

3) What is the percentage of global fresh water that is in glacial form?

4) Important dates: Friday – Extra credit is due, Aquarium data is due.

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Bellwork: 10/0/2012

1) DO NOT change your water yet!

2) Arrange the carbonate compounds from the carbonate buffering system from most basic to most acidic. What defines an acid? Base?

3) Which of the toxins used yesterday & today are hydrophobic? How can you tell?

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Bellwork: 10/05/2012

1. Describe the effects of the following situations on microbes within the environment, how that can effect higher-level organism, and how the situation could be remediated & prevented in the future:a) A factory that produces DEET uses water from a local bay to

cool its machinery. A small amount DEET leaks into the bay once a week when the machines are cleaned.

b) An explosion on an oil platform in the Gulf of Mexico causes oil to spew into Gulf for two straight weeks.

c) An individual who refuses to properly dispose of his trash chooses instead to dump his trash in the Brazos River. There is a very high concentration of half-filled drain cleaner in his trash that quickly moves into the water.

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Extra Credit Opportunity (1/2 Exam Grade)

Create 10 LAMINATED note cards with the following information:

Front of Notecard:

Large, clear, color picture of an organism in the classroom

Common name & Scientific name

Back of the Notecard:

What are some unique and/or defining characteristics of the species?

What are the differences between males & females if there are any?

Where do they live?

What do they eat?

Due Friday: 10/05/2012

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Instructions:

1. Get a microscope, plastic slide, and plastic pipette.2. Place one or two drops from your water sample onto the slide &

use the lower two objectives of the microscope to find any large & mobile organisms in the sample. Draw a detailed picture of the organism you find & describe its movement. Get your sketch initialed by Mr. Young.

3. Add one of the eight available toxins to your sample while your lab partner is looking through the microscope. After several minutes, draw & describe the resulting effect on the organism you were observing. Get your sketch initialed by Mr. Young.

4. Thoroughly rinse off the slide and repeat the above steps with similar organisms until you have used all eight toxins.

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Questions:

1. What were the responses the organisms had to the toxins?2. Which toxin seemed to have the greatest effect on the

microscopic organisms? The least? Why do you think this is?3. What are the expected effects to an ecosystem if the lower-level

organisms died off?4. Many of the water samples contain very high levels of nitrates

(TAN) and very low DO. Why can the microbes you found survive at these chemical levels?

5. Name some ideas of how to keep these toxins out of our water supplies. How can these toxins be removed from a water system once they are introduced?

6. List the toxic from most dangerous to least dangerous according to what you thought about these toxins before doing this lab.

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Questions: Review

1. What were the responses the organisms had to the toxins?- Motor oil

- Transmission Fluid

- DEET

- Bleach

- Drain Cleaner

- Oxalic Acid (Stove Cleaner )

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Questions: Review

1. What were the responses the organisms had to the toxins?- Motor oil relatively unreactive, less dense than water

- Transmission Fluid relatively unreactive, less dense than water

- DEET Causes cells to express caspase is apoptosis cascade

- Bleach Causes the proteins in cells to unravel

- Drain Cleaner Cell membranes lose integrity & lyse

- Oxalic Acid (Stove Cleaner) triggers apoptosis & overwhelms biochemical reactions

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Questions:

2. Which toxin seemed to have the greatest effect on the microscopic organisms? The least? Why do you think this is?

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Questions:

3. What are the expected effects to an ecosystem if the lower-level organisms died off?

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Questions:

4. Many of the water samples contain very high levels of nitrates (TAN) and very low DO. Why can the microbes you found survive at these chemical levels?

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Questions:

5. Name some ideas of how to keep these toxins out of our water supplies. How can these toxins be removed from a water system once they are introduced?

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Questions:

6. List the toxic from most dangerous to least dangerous according to what you thought about these toxins before doing this lab.

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Water Chemistry

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Drinking Water Quality

Source Treatment Distribution

What do consumers care about?

How can that be protect and provided?

What are the most important chemical parameters?

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Chemical Compounds in Water

Inorganic

Salts dissolve in water and become ions

NaCl Na+ + Cl- H2SO4 2H+ + SO4-2

Acids and bases dissociate depending on pH

Organic (contain C, H, O and other elements)

Hydrophilic compounds associate with water

Ex. Organic acids and phenols dissociate depending on pH

CH3CO2H H+ + CH3CO2-

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Alkalinity

Alkalinity is a measure of water’s ability to buffer

against addition of an acid, i.e., ability to resist change

of pH upon addition of an acid

Must understand carbonate system in water to

understand alkalinity

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CO2(g)

CO2(aq)

H2O

H2CO3

H+

HCO3–

H+

CO32-

CaCO3(s)limestone

Ca2+

Carbonate SystemCarbonic Acid

Bicarbonate

Carbonate

pH

8 1064

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Bellwork: 09/29/2014

1. As carbonic acid reacts to for bicarbonate and finally carbonate, which ion is liberated out into the surrounding water?

2. What percent of the planet’s water is considered fresh water? Of that percent, what percent is groundwater?

3. Your aquarium data in the form of an excel spread sheet with graphs is due to [email protected] by midnight Friday night.

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Carbonate Chemistry

-0.5

0.0

0.5

1.0

4 6 8 10 12Fra

ctio

n o

f CT

OT

pH

[HCO3–]

[HCO3–]

[HCO3–][H2CO3]

[H2CO3]

[CO32-]

[CO32-]

CTOT = [H2CO3] + [HCO3-] + [CO[CO33

2-2-]]

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Alkalinity

Alkalinity = sum of equivalents of all species that can

neutralize an acid

Alk (eq/L) = (HCO3–)+(CO3

2-)+(OH–)-(H+)

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Microbial Examples

Diatoms:

“Brown Algae” – most common type of phytoplankton

Fresh and Salt Water phytoplankton

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Microbial Examples

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Microbial Examples

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Microbial Examples

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Microbial Examples

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Microbial Examples

Euglena:

Single-Celled Protist

Has both plant and animal features (chloroplasts &

consumes other organisms)

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Microbial Examples

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Microbial Examples

Volvox:

Type of green algae

Heavily flagellated

Rolling/swimming algae cities

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Microbial Examples

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Microbial Examples

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Microbial Examples

Paramecium:

Single-Celled Protist

Covered in cilia

Freshwater organisms that generally feed on bacteria

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Microbial Examples

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Microbial Examples

Hydra:

Simple fresh water animal

Has a unique regenerative ability

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Microbial Examples

Daphnia:

“Water fleas”

Used as an indicator species

Consumes yeast, algae, and detritus

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Microbial Examples

Amoeba:

Single-Celled Protist

Uses “arms” to move

Consumes other organisms via phagocytosis

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Bellwork: 10/03/2013

Don’t start working with the microscopes yet!

1.You 6-weeks aquarium data is due to [email protected] by midnight tomorrow. Remember, this is a major grade.

2.Define alkalinity:

3.What is the formula for bicarbonate & the approximate pH of a water source that is high in bicarbonate?

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Bellwork: 10/07/2013

1. From carbon dioxide gas to limestone (calcium carbonate), draw out the reactions for the carbonate buffering system:

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CO2(g)

CO2(aq)

H2O

H2CO3

H+

HCO3–

H+

CO32-

CaCO3(s)limestone

Ca2+

Carbonate SystemCarbonic Acid

Bicarbonate

Carbonate

pH

8 1064

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The End of the 6-weeks is Friday: Current Failures

3rd Period: 87.52 % Average 5th Period: 90.05% Average

100040640 (64)

100022659 (64)(F1)*

4th Period: 85.96% Average 100023533 (68)**** 6th Period: 82.68% Average

100042538 (13)(M1,MP,F2)100041128 (36)(M2)**M = Missing

F = Failed1, 2 = Exam NumberP = Project* = an additional class

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Ecological Concepts

Microbes account for ~ 50% of all biomass on Earth

They are ubiquitous on the surface and deep within

the earth

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Ecological Concepts

The diversity of microbial species in an ecosystem can

be expressed in two ways

Species richness: the total number of different species

present

Species abundance: the proportion of each species in an

ecosystem

Microbial species richness and abundance is a function

of the kinds and amounts of nutrients available in a

given habitat

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Microbial Species Diversity

Figure 23.1

High Species Richness and Low to Moderate Abundance

Low Species Richness and High Abundance

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Microbial Ecosystems

Guilds

Metabolically related microbial populations

Sets of guilds form microbial communities that

interact with other larger organisms and abiotic

factors in the ecosystem

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Populations, Guilds, and Communities

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Environments and Microenvironments

The growth of microbes depends on resources and growth

conditions

Difference in the type and quantity of resources and the

physiochemical conditions of a habitat define the niche for each

microbe

For each organism there exists at least one niche in which that

organism is most successful (prime niche)

Microenvironment

The immediate environmental surroundings of a microbial

cell or group of cells

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Bellwork: 10/04/2012

1. Give an example of a guild.

2. How is organic different than inorganic? Give two examples of

each.

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Biofilms: Microbial Growth on Surfaces

Surfaces are important microbial habitats because

Nutrients adsorb to surfaces

Microbial cells can attach to surfaces

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Biofilms: Microbial Growth on Surfaces

Biofilms

Assemblages of bacterial cells adhered to a surface

and enclosed in an adhesive matrix excreted by the

cells

The matrix is typically a mixture of polysaccharides

Biofilms trap nutrients for microbial growth and help

prevent detachment of cells in flowing systems

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Examples of Microbial Biofilms

Cross-Sectional View of Experimental Biofilm

Natural Biofilm on a Leaf Surface

Biofilm of Iron-Oxidizing Prokaryotes Attached to Rocks

Biofilm on medical catheter

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Biofilm Formation

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Biofilms: Advantages and Control

Bacteria form biofilms for several reasons

Self-defense

Biofilms resist physical forces that sweep away

unattached cells, phagocytosis by immune system cells,

and penetration of toxins (e.g., antibiotics)

Allows cells to remain in a favorable niche

Allows bacterial cells to live in close association with

one another

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Freshwater Environments

Biochemical Oxygen Demand (BOD)

The microbial oxygen-consuming capacity of a body of

water

Fish Kills from pollution resulting in increased BOD.

Result: Asphyxiation

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Open Oceans

Most of the primary productivity in the open oceans

is due to photosynthesis by prochlorophytes

Prochlorococcus accounts for

> 40% of the biomass of marine phototrophs

~50% of the net primary production

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Bellwork: 10/08/2013

1. How is a psychrophilic organism different than a barotolerant organism?

2. Prochlorococcus cells are responsible for about how much primary production within the oceans?

3. What is the formula for: bicarbonate, carbonate, and carbonic acid?

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Bellwork: 10/15/2013

1. What are prochlorococcus & why are they important?

2. What is BOD, and how can it be affected by an algal bloom?

3. When considering bacteria, what are three advantages in forming biofilms?

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Percentage of Total Prokaryotes in the North Pacific Ocean

Figure 23.19

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The Deep Sea and Barophilism

Deep sea microbes are

Psychrophilic (cold-loving) or psychrotolerant

Barophilic (pressure-loving) or barotolerant

Black SmokerHydrothermal vent

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Growth of Barotolerant and Barophilic Bacteria

Figure 23.20

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Hydrothermal Vent Microbial Ecosystems

Deep-sea hot springs

(hydrothermal vents)

support thriving animal

communities that are

fueled by

chemolithotrophic

microbes

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Hydrothermal Vent Microbial Ecosystems

Diverse invertebrate communities

develop near hydrothermal vents,

including large tube worms, clams,

mussels

Chemolithotrophic prokaryotes that

utilize reduced inorganic materials

emitting from the vents form

endosymbiotic relationships with

vent invertebrates such as vent

tube worms

Tube Worms

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Hydrothermal Vent Microbial Ecosystems

Black Smokers

Thermal vents that

emit mineral-rich hot

water (up to 350°C)

forming a dark cloud

of precipitated

material on mixing

with cold seawater

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Microbial Ecology: Biogeochemical Cycles

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The Carbon Cycle

Carbon is cycled through all of Earth’s major carbon reservoirs

(atmosphere, land, oceans, sediments, rocks, and biomass)

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The Carbon Cycle

CO2 in the atmosphere is the most rapidly transferred

carbon reservoir

CO2 is fixed primarily by photosynthetic land plants and

marine microbes (autotrophs fix carbon dioxide)

CO2 is returned to the atmosphere by respiration of animals

and chemoorganotrophic microbes as well as by the

activities of humans.

Microbial decomposition is the largest source of CO2

released to the atmosphere

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Nitrogen Cycle

Nitrogen is essential for amino acids, nucleic acids, etc.

80% of atmosphere is molecular nitrogen N2

For plants to use nitrogen it must be fixed (combined with other

elements). Only a few species of bacteria can fix nitrogen!!

Nitrogen fixation: nitrogen gas is converted to ammonia (requires

enzyme nitrogenase)

Free-living nitrogen-fixing bacteria

Symbiotic nitrogen-fixing bacteria

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Nitrogen Cycle

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Degradation of Chemical by Microbes

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Bioremediation

Bioremediation

Refers to the cleanup of oil, toxic chemicals, or

other pollutants from the environment by

microorganisms

Often a cost-effective and practical method for

pollutant cleanup

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Petroleum Biodegradation

Prokaryotes have been used in bioremediation of

several major crude oil spills

Oil Spilled into the Mediterranean Sea

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Environmental Consequences of Large Oil Spills

Contaminated Beach in Alaska containing oil from the Exxon Valdez spill of 1989

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Environmental Consequences of Large Oil Spills

Center rectangular plot (arrow) was treated with inorganic nutrients to stimulate bioremediation

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Petroleum Biodegradation

Diverse bacteria, fungi, and some

cyanobacteria and green algae can oxidize

petroleum products aerobically

Oil-oxidizing activity is best if temperature and

inorganic nutrient concentrations are optimal

Hydrocarbon-degrading bacteria attach to oil

droplets and decompose the oil and dispense

the slick

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Petroleum Biodegradation

Some microbes can produce petroleum

Particularly certain green algae

Plastics of various types are xenobiotics that are not readily

degraded by microbes

The recalcitrance of plastics has fueled research efforts into a

biodegradable alternative (biopolymers)

The green alga Botryococcus braunii shown here is excreting oil droplets