Microbiology, Ch 29, Nester's 9th - all correct

The approximate BOD value for raw sewage is A. 2000-7000 milligrams per milliliter. B. 500-800 grams per milliliter. C. 0-50 kilograms per milliliter. D. 300-400 milligrams per liter

300-400 milligrams per liter p.787 - the BOD of raw sewage is approximately 300-400 mg/liter, whereas the dissolved oxygen content of natural waters is generally 5-10 mg/liter. So adding raw sewage to a lake could easily deplete the dissolved oxygen from the water.

The compost pile temperature at which pathogens, but not thermophiles, are killed is about A. 20-30ºC. B. 55-66ºC. C. 62-75ºC. D. 90-100ºC.

55-66ºC. - achieving high temperatures is important to kill pathogens that might be present in the solid waste. Thermophilic organisms (45-70ºC) thrive at the high temperature, so they continue decomposing the material.

Other microorganisms besides coliforms that have been used as indicators of fecal contamination may be A. Clostridia. B. Enterococci. C. bacteriophages. D. Bacteroides. E. Clostridia, Enterococci AND bacteriophages

Clostridia, Enterococci AND bacteriophages - but NOT bacteroides.

The oxygen consuming property of a wastewater sample is designated by the term biological nitrogen demand. lagooning. lagooning ANF stabilization. stabilization. biochemical oxygen demand.

BOD - biochemical oxygen demand

Other microorganisms besides coliforms that have been used as indicators of fecal contamination may be all of the following EXCEPT Bacteroides. Clostridia, Enterococci AND bacteriophages. Clostridia. bacteriophages. Enterococci.

Bacteroides. p.794

Above this is all correct (I know because they were mine.)

Below - did my best to make sure.

Advanced treatment of sewage A. is done to prevent nutrient enrichment. B. is done to prevent possible overproduction of algae and other organisms. C. involves the removal of phosphates and nitrogen compounds. D. All of the choices are correct.

D. All of the choices are correct. p.789 - advanced treatment is often designed to REMOVE AMMONIA, NITRATES AND PHOSPHATES - compounds that foster growth of algae and cyanobacteria in receiving waters (so remove so to PREVENT POSSIBLE OVERPRODUCTION OF ALGAE AND OTHER ORGANISMS). The concentration of these nutrients is normally low in receiving waters which limits the growth of photosynthetic organisms but add the nutrients and see them multiply, BOD increase and other forms of aquatic life threatened (so advanced treatment IS DONE TO PREVENT NUTRIENT ENRICHMENT of the receiving waters so that doesn't happen).

Which of the following statements about landfills is FALSE? Dangerous levels of methane gas can accumulate. The excavated site has a plastic liner to prevent wastes from leaching into groundwater. Degradation of wastes is rapid and inexpensive. Recycling greatly reduces the amount of wastes sent to landfills. All of the answer choices are true.

Degradation of wastes is rapid and inexpensive.

The compost pile temperature at which pathogens, but not thermophiles, are killed is about 20-30ºC. T/F

False 55 to 66 degrees Celsius

The conversion of organic to inorganic matter is called co-metabolism. T/F

False Co-metabolism occurs when an enzyme produced by a microbe to degrade an added substrate in an environment degrades a pollutant as well.

High BOD values reflect small amounts of degradable organic matter in a sample of wastewater or other material. T/F

False High BOD values reflect large amounts of degradable organic matter in a sample of wastewater or other material.

If a compost pile is turned frequently and other conditions are adequate for aerobic digestion, the composting can be completed in 6 weeks. T/F

True

The term "potable water" refers to water that is not necessarily pure, but is safe to drink. T/F

True

Trickling filters may be used in place of activated sludge in secondary sewage treatment. T/F

True

Zero coliforms per 100 ml of water is considered safe for treated potable water. T/F

True - I put false, wrong! So definitely true.

The activated sludge method can be stopped by the presence of toxic industrial wastes. T/F

True - the toxic wastes could kill the microbial population. p.787

An effective means used early in the 19th century to clear water of the majority of bacteria was the use of chlorine iodine sand filters alcohol

- sand filters sand filtration (since the 1920s) - Later, Koch showed that this kind of filtration yields clear water and removes most bacteria. p.786

Why does secondary treatment of wastewater require O2?

- to encourage microbial growth. p.787 - microbial growth is actively encouraged during secondary treatment, allowing aerobic organisms to oxidize the biologically degradable organic material to carbon dioxide and water. - Secondary processes rely on the aerobic activity of bacteria.

In treating an oil spill, why might biostimulation be preferred over bioaugmentation? In fact, biostimulation is not generally favored as an approach. Biostimulation often leads to the generation of antibiotic—resistant microbes, which become a problem for other organisms in the environment. Bioaugmentation is the favored approach because adding nutrients to the area simply enhances the activities of the bacteria already present. Adding new microbes (bioaugmentation) poses some risk—when new microbes are added to an environment, the consequences of those additions on resident populations are unknown. Adding nutrients (biostimulation) is safer because once those nutrients are used up, the microbial populations are likely to return to their original levels. Biostimulation and bioaugmentation are always used simultaneously. This is done because neither one of these approaches works well individually. Adding bacteria to an environment will never be successful unless nutrients are also added to that environment. Bioaugmentation involves adding novel microbes to boost the populations of resident microbes. These novel microbes are highly genetically engineered to enhance their abilities to metabolize pollutants such as oil, so are very effective. Biostimulation merely involves adding nutrients, so all microbes are favored, even those not performing a useful function. Biostimulation involves adding novel microbes to boost the populations of resident microbes. These novel microbes are generally genetically engineered to enhance their abilities to metabolize pollutants such as oil, so are very effective. Bioaugmentation merely involves adding nutrients, so all microbes are favored, even those not performing a useful function.

Adding new microbes (bioaugmentation) poses some risk—when new microbes are added to an environment, the consequences of those additions on resident populations are unknown. Adding nutrients (biostimulation) is safer because once those nutrients are used up, the microbial populations are likely to return to their original levels.

Sludge A. is a byproduct of sewage treatment. B. may be a source of pollution. C. takes up space in a land fill. D. All of the choices are correct

All of the choices are correct.

Wastewater treatment decreases the amount of phosphate. biodegradable carbon. pathogens. ammonia and nitrate. All of the choices are correct.

All of the choices are correct.

Which of the following play some role in sewage treatment? A. activated sludge B. trickling filter C. septic tank D. lagooning E. All of the choices are correct

All of the choices are correct.

Which of the following is used to cause flocculation? Methane Charcoal Chlorine Aluminum potassium phosphate (alum) Natrium potassium phosphate (nalum)

Aluminum potassium phosphate (alum)

Which statement does NOT apply to water treatment? Advanced treatment of wastewater is often designed to remove ammonia, nitrates, and phosphates. Secondary treatments are designed to convert suspended solids into inorganic compounds and microbial biomass. The primary treatment of wastewater is a physical process designed to remove materials that settle out. An important goal of wastewater treatment is the increase of the BOD that stimulates microbial growth. Biosolids that result from anaerobic digestion of sludge can be used to improve soils and promote plant growth.

An important goal of wastewater treatment is the increase of the BOD that stimulates microbial growth. Goal is to DECREASE the BOD

What is the difference between biostimulation and bioaugmentation? Biostimulation is a bioremediation process designed to remove pollutants from an environment. Bioaugmentation is a method used in laboratories to promote the growth of fastidious microbes. Biostimulation generally occurs in situ and is less disruptive while bioaugmentation is performed off site using a bioreactor, a large tank designed to accelerate microbial processes. Bioaugmentation enhances the growth of local microbes in a contaminated site by providing additional nutrients while biostimulation relies on activities of microorganisms added to the contaminated material, complementing the resident population. Biostimulation is a method of degrading environmental pollutants while bioaugmentation is a method of supplementing microbial populations in landfills and composters. Biostimulation enhances the growth of local microbes in a contaminated site by providing additional nutrients while bioaugmentation relies on activities of microorganisms added to the contaminated material, complementing the resident population.

Biostimulation enhances the growth of local microbes in a contaminated site by providing additional nutrients while bioaugmentation relies on activities of microorganisms added to the contaminated material, complementing the resident population.

What is the purpose of grinding yard waste before putting it into composting piles? Grinding yard waste is a method for introducing degradative microbes into the mix, needed for composting. Grinding the material breaks down some of the components that microbes cannot digest, such as cellulose. Grinding the material increases the surface area available for microbial action, so that the material can be degraded more efficiently. Grinding the matter introduces large amounts of oxygen into the material, which is essential for microbial degradation of matter. Bacteria are microscopic organisms and can only break down very small pieces of matter, which grinding produces.

Grinding the material increases the surface area available for microbial action, so that the material can be degraded more efficiently.

Select the pair that is INCORRECTLY matched. High BOD—low organic content Potable water—lacks pathogenic microbes and harmful chemicals Total coliforms—lactose-fermenting members of the family Enterobacteriaceae Primary treatment—removal of material that settles High BOD—high organic content

High BOD - low organic content This one is almost identical to a multiple choice question at the end of the chapter.

Why do water-testing procedures look for coliforms rather than pathogens? - It is always somewhat dangerous to culture pathogens in a laboratory setting - people in the lab are at risk of contracting serious disease. It is much safer to test for coliforms which simply indicate that humans have been swimming in the water. - Pathogens are seldom found in water. Testing for coliforms is a way of determining whether there is any human normal microbiota contamination in that water, which should then be treated with chlorine. - Pathogens and coliforms are the same thing. Testing for one is also testing for the other. - It is not possible to test for all of the potential pathogens in water, so indicator organisms such as coliforms are used. These microbes are found in feces, so finding them suggests fecal contamination, and indicates a greater likelihood that intestinal pathogens are also present. - Pathogens are extremely fastidious in their nutrient requirements and require special growth conditions. Coliforms are easier to culture in a laboratory setting, so it makes sense to test for these rather than for actual pathogens.

It is not possible to test for all of the potential pathogens in water, so indicator organisms such as coliforms are used. These microbes are found in feces, so finding them suggests fecal contamination, and indicates a greater likelihood that intestinal pathogens are also present.

Please select the statement that does NOT apply to strategies of bioremediation. Bioaugmentation involves adding microorganisms to contaminated material, complementing the resident population. Providing optimal bacterial growth conditions is likely to promote pollutant degradation. Biostimulation enhances pollutant degradation by enhancing growth of resident microbes in a contaminated site through providing additional nutrients. Low temperature, arid conditions and acidic pH will speed up the rate of pollutant degradation. Co-metabolism occurs when an enzyme produced by a microbe to degrade an added substrate in an environment degrades a pollutant as well.

Low temperature, arid conditions and acidic pH will speed up the rate of pollutant degradation. - it's an increase in temperature, near neutral pH and optimal moisture that will speed up the rate of pollutant degradation.

Which of the following cannot be used in composting? Nutrient-poor potting soil Grass clippings Vegetable peelings Meats and fats Leaves

Meats and fats

Which of the following is a disadvantage of landfills? Methane gas that is produced in landfills as the organic waste material anaerobically decomposes must be removed. Only a limited number of sites are available for making landfills near urban and suburban areas. Pollutants such as heavy metals and pesticides frequently leak from landfill sites, reaching underground aquifers and contaminating drinking water, AND only a limited number of sites are available for making landfills near urban and suburban areas. Pollutants such as heavy metals and pesticides frequently leak from landfill sites, reaching underground aquifers and contaminating drinking water. Methane gas that is produced in landfills as the organic waste material anaerobically decomposes must be removed AND only a limited number of sites are available for making landfills near urban and suburban areas.

Methane gas that is produced in landfills as the organic waste material anaerobically decomposes must be removed AND only a limited number of sites are available for making landfills near urban and suburban areas. p.795

What are indicator organisms? Microbes that alert a physician to the presence of a gastrointestinal illness. Microbes that are contaminants in laboratory media. Microbes whose presence in an environment suggests the presence of animal urine. Microbes whose presence in an environment suggests fecal contamination. All of the choices are correct.

Microbes whose presence in an environment suggests fecal contamination.

Which statement is FALSE? Trickling filter systems are used for secondary water treatment. Chlorine, ozone and UV light can be used to disinfect water. Artificial wetlands provide a habitat for wildlife. Methane is a by-product of anaerobic digestion. Removal of nitrates by microorganisms requires aerobic conditions.

Removal of nitrates by microorganisms requires aerobic conditions. p.789 - anaerobic respiration of nitrifying bacteria

Which would be more likely to cause illness: a water sample that tested positive for coliforms or one that tested positive for E. coli O157:H7? Both would be equally capable of causing illness because all coliforms cause illness. The E. coli O157:H7 sample would be more likely to cause illness. This strain of bacterium is highly pathogenic and capable of causing kidney damage. Neither; there is usually a small amount of coliforms (including E. coli O157:H7) in all water. The coliform-positive sample would be more likely to cause illness. Coliforms are inherently more pathogenic than the weak O157:H7 lab strain of E. coli. The coliform-positive sample would be more likely to cause illness. Coliforms indicate the presence of fecal contamination, which always leads to illness.

The E. coli O157:H7 sample would be more likely to cause illness. This strain of bacterium is highly pathogenic and capable of causing kidney damage.

Why is oil not degraded when in a natural habitat underground, yet susceptible to bioremediation in an oil spill? a) The bacteria can't be given the right amounts or types of nutrients to foster an increase in their number deep underground. Nearer the surface, human intervention can increase the factors that will raise the microbe quantity. b) It IS degraded underground-but it happens at a much slower rate because a portion of the cycle is photosynthetic in nature. This process is dramatically increased nearer to the water's surface. c) The high pressure the oil is subjected to underground prevents bacteria from growing and consuming it. d) The bacteria that degrade the oil require a higher than normal salt content, much like what is found in seawater. Underground, they lack this salt level.

The bacteria can't be given the right amounts or types of nutrients to foster an increase in their number deep underground. Nearer the surface, human intervention can increase the factors that will raise the microbe quantity. p.797 - petroleum-degrading bacteria are naturally present in seawater, but they degrade oil at a very slow rate because the low levels of certain nutrients, including nitrogen and phosphorus, limit their growth. To enhance bioremediation of oil spills, a fertilizer containing these nutrients - and which adheres to oil - was developed. When this fertilizer is applied to an oil spill, microbial growth is stimulated, leading to at least a threefold increase in the speed of degradation. - for oil spills - biostimulation is better than bioaugmentation.

As much as 95% of BOD can be removed during secondary treatment. T/F

True

What is the purpose of coagulation in drinking water treatment? Pollutants such as lead are combined into clumps using toxic chemicals, for easy removal. To bind together pollutants, bacteria, and other organisms for removal by chemicals. Suspended material is combined using toxic chemicals for easy removal from water. When suspended material clumps, it sinks and can be easily removed. Antibodies are used bind bacteria into large masses that can be removed by filtration.

When suspended material clumps, it sinks and can be easily removed.

A high BOD value means a small number of viruses are present AND a large amount of oxygen has been used. a small amount of oxygen has been used AND a large amount of degradable organic matter is present. a large amount of degradable organic matter is present AND a small number of viruses are present. a large amount of oxygen has been used AND a large amount of degradable organic matter is present. a large amount of oxygen has been used AND a small amount of degradable organic matter is present.

a large amount of oxygen has been used AND a large amount of degradable organic matter is present. p.787 - high BOD values indicate that large amounts of degradable materials are present, resulting in the consumption of correspondingly large amounts of oxygen during biological degradation of the environment.

Why would soil and water be added to a compost pile?

adds microbes and moisture to degrade organics

Bioaugmentation adds specific microorganisms to a contaminated site. aims at enhancing the growth of the resident population of microbes. is typically done offsite. usually utilizes genetically engineered bacteria. depends on competition between resident and added microbes.

adds specific microorganisms to a contaminated site.

Bioaugmentation: a) adds specific microorganisms to the polluted site. b) is typically done offsite. c) only enhances the growth, onsite, of the resident population of microbes. d) usually utilizes genetically engineered bacteria.

adds specific microorganisms to the polluted site. - 1 of 2 bioremediation strategies. - relies on the activities of microorganisms added to the contaminated material, complementing the resident population. - an example is the activated sludge process used during secondary treatment of wastewater - sludge from previous batch is added to the effluent (liquid) of the new cycle

In sewage treatment, the removal of phosphates and nitrogen compounds is achieved during advanced treatment. quaternary treatment. secondary treatment. primary treatment. All of the choices are correct.

advanced treatment

Synthetic compounds are most likely to be biodegradable if they are chemically similar to naturally occurring substances. are present in very large amounts. have three chlorine atoms per molecule. are chemically different form naturally occurring substances. None of these is true.

are chemically similar to naturally occurring substances. This question is from the multiple choice questions at the end of the chapter.

The accepted method of testing water supplies for the possible presence of pathogens is to determine the presence of A. Streptococci. B. coliforms. C. Staphylococci. D. Streptomyces.

coliforms

Considering that Cryptosporidium oocysts are resistant to chlorine, which step in water treatment protects us from this pathogen? Sedimentation Filtration Settling Coagulation Disinfection and storage

filtration

Vibrio cholerae is most often associated with touching animals. breathing air. eating food. drinking water. having unprotected sex.

drinking water.

Water treatment processes for drinking water A. are similar to wastewater treatment. B. are only necessary when using recycled water. C. includes disinfection but not litration. D. has no biological treatment phase

has no biological treatment phase - for wastewater, secondary treatment is a biological process that converts most of the suspended solids to inorganic compounds and cell mass that can be removed. Microbial growth is actively encouraged, allowing aerobic organisms to oxidize the biologically degradable organic material to carbon dioxide and water. p.787 - This doesn't happen for drinking water.

Advanced treatment of sewage involves the removal of phosphates and sulfur compounds. is done to promote nutrient enrichment. is done to promote growth of photosynthetic organisms. is done to prevent possible overproduction of algae and other organisms. All of the choices are correct.

is done to prevent possible overproduction of algae and other organisms.

The activated sludge process is used during secondary treatment of sewage. is meant to increase the BOD. is meant to convert inorganic to organic matter AND is meant to increase the BOD. is meant to convert inorganic to organic matter. removes large objects from the sewage.

is used during secondary treatment of sewage.

Coliforms are Gram-positive. spore-forming. lactose-fermenting. coccus-shaped. All of the choices are correct.

lactose-fermenting Enterobacteriaeae - Gram-negative rods, non-spore formers, anaerobic, lactose fermentors.

Effective treatment of wastewater/sewage is reflected in a(n) increase in sulfur. lower BOD. higher BOD. unchanging BOD. decrease in biomass.

lower BOD

The anaerobic organisms used in sewage treatment may produce the useful product(s) nitrogen AND carbon monoxide. methane. nitrogen. carbon monoxide. oxygen.

methane

What is the advantage of removing phosphates and nitrates from wastewater?

p.789 - advanced treatment is often designed to REMOVE AMMONIA, NITRATES AND PHOSPHATES - compounds that foster growth of algae and cyanobacteria in receiving waters (so remove so to PREVENT POSSIBLE OVERPRODUCTION OF ALGAE AND OTHER ORGANISMS). The concentration of these nutrients is normally low in receiving waters which limits the growth of photosynthetic organisms but add the nutrients and see them multiply, BOD increase and other forms of aquatic life threatened (so advanced treatment IS DONE TO PREVENT NUTRIENT ENRICHMENT of the receiving waters so that doesn't happen).

All of the following are methods used to detect total coliforms in a water sample EXCEPT ones that are: - ONPG/MUG test - Presence/Absence test - MPN method - Membrane Filtration

p.793 - methods used to detect total colifroms in a water sample: - ONPG/MUG test - lactose-fermenting bacteria hydrolyze ONPG - turns yellow (all coliforms do this) - E. coli produces an enzyme that hydrolyzes MUG, making a (blue) fluorescent compound - Presence/Absence test - add 100 ml water to lactose-containing broth that is selective for G- rods - inverted tube to trap gas. Yes gas, test tube to confirm coliforms are present. - Most probably number (MPN) method - successive dilutions, inverted tubes to trap gas, further testing to confirm coliforms. - Membrane Filtration - filter that retains bacteria. Place filter on a lactose containing selective and differential agar medium.

The problem(s) with using sludge as a fertilizer is/are the A. presence of heavy metals and similar pollutants. B. presence of pathogenic organisms and viruses. C. inhibitory effect it has on plant growth. D. stimulatory effect it has on methane production. E. presence of heavy metals and similar pollutants AND presence of pathogenic organisms and viruses.

presence of heavy metals and similar pollutants AND presence of pathogenic organisms and viruses.

Pollutant degradation may be enhanced by lowering the temperature. providing dry conditions. maintaining an acidic pH. providing adequate nutrients. All of the choices are correct.

providing adequate nutrients.

The term "potable water" refers to water that is only good for irrigation of crops. safe to drink. in carrying containers. safe to swim in but not to drink. contaminated with chemicals.

safe to drink

A site used for disposal of non-hazardous solid wastes in a manner that minimizes damage to human health and the environment is a(n) sanitary landfill. septic tank. activated sludger. water treatment facility. composter.

sanitary landfill

In which phase of sewage treatment are trickling filters sometimes used? A. primary treatment. B. secondary treatment. C. tertiary treatment. D. quaternary treatment.

secondary treatment

If a compost pile is turned frequently and other conditions are adequate for aerobic digestion, the composting can be completed in 1 month. 1 day. six months. six weeks. three years.

six weeks