UNIT 8

Based on the data in the graph, which of the following should be used to calculate the difference in LD50LD50 for the two different species of mice? Responses (200mg−100mg)2 490mg50−575mg50 575mg−490mg (600mg×50)30 days

575mg−490mg

Water from which of the following locations on the map would best serve as a control group for the study? Responses A B C D

A

Based on the data in the graph, which of the four chemicals is the most toxic to amphibians regardless of dose? A A B B C C D

A A

Which of the following is an example of a point source of pollution? A A leaking septic tank B Agricultural pollution from a group of cattle farms C Runoff following road construction D Acid mine drainage

A A leaking septic tank

Which of the following approaches would best decrease the impact of frequent flooding in a community that is subject to the hazard of flooding? A Construct wetland areas near the rivers and streams. B Remove forested areas around all streams and rivers and change land use to agriculture. C Increase the height of natural levees downstream from the community. D Encourage developers to build housing developments on the floodplain.

A Construct wetland areas near the rivers and streams.

Which of the following is the most likely impact of thermal pollution from power plants on a river ecosystem? A Decreased oxygen levels because warm water holds less dissolved gas than cold water does B Increased sedimentation because minerals precipitate out of the water column in warm water C Reduced growth rates of primary producers such as aquatic plants and algae D Decreased metabolic rates of aquatic animals exposed to the heated water

A Decreased oxygen levels because warm water holds less dissolved gas than cold water does

Scientists are interested in studying the bioaccumulation of mercury in different species of dolphins exposed to the same concentration of mercury. The dolphins in the study will be of similar age and living in the same habitat. Which of the following best identifies a testable hypothesis for the study? A Different species of dolphins will have different levels of mercury in their fatty tissues depending on the species' ability to absorb and excrete mercury. B Dolphins will have the highest levels of mercury in their fatty tissues when they are exposed to the highest concentration of mercury. C Dolphin species that are not exposed to mercury in the water will still have trace levels of mercury in their muscle tissues from exposure through air. D The concentration of mercury in the tissues of different species of dolphins is dependent on the life span of the species and on the number of offspring produced.

A Different species of dolphins will have different levels of mercury in their fatty tissues depending on the species' ability to absorb and excrete mercury.

Which of the following pollutants would most likely be responsible for gender imbalance in a population of frogs in which all observed frogs are female? A Endocrine disruptors B Carcinogens C Animal waste from farms D Fertilizers

A Endocrine disruptors

Based on the data in the graph, which of the following likely occurred from 1960 to 2015 because of changes in solid waste disposal methods? A Fewer natural resources needed to be extracted. B Groundwater contamination declined. C Less carbon dioxide was released into the atmosphere. D Less land was used for landfills.

A Fewer natural resources needed to be extracted.

Which of the following strategies will best help to protect mangrove habitats? A Limiting coastal development and maintain a shoreline buffer zone B Increasing aquaculture operations to reduce overfishing C Increasing subsidies for hydroelectric dam construction D Encouraging land use changes in areas surrounding mangroves to shift to agriculture

A Limiting coastal development and maintain a shoreline buffer zone

An individual is exposed to the water in the stream from which the sample show in the graph was taken. If the individual was exposed to the highest dose of the bacteria, which of the following bacteria would have the lowest probability of causing illness if ingested? Responses A. C. jejuni B. E. coli C. Salmonella spp . D. Newly discovered bacterium

A. C. jejuni

Which of the following best describes why DDT is classified as a persistent organic pollutant? A. DD T is very stable, and as much as 50% of the original concentration can remain in the soil 15 years after the initial application. B. DDT can be used to control diseases, such as malaria and typhus, that are spread by insects. C. DDD T is detected in food worldwide and the general human population is most commonly exposed to the toxin through food. D. DDT has both short-term acute and long-term chronic health effects in both humans and wildlife.

A. DD T is very stable, and as much as 50% of the original concentration can remain in the soil 15 years after the initial application.

Researchers suspect that sewage leaked into the Moose River. Rates for which of the following diseases should be used to determine whether the human population using the river as a source of drinking water was exposed to sewage? Responses A. Dysentery B. Mesothelioma C. Asthma D. Malaria

A. Dysentery

Based on the diagram, which of the following is associated with the primary treatment of sewage? Responses A. Grit chamber B. Aeration tank C. Effluent D. Activated sludge

A. Grit chamber

Which of the following is the best example of a point source pollutant? Responses A. Oil tanker spill B. Farm field C. Golf course D. Parking lot

A. Oil tanker spill

Which of the following best explains why top predators can have up to 60 times as much of persistent organic pollutant (POPPOP) as their prey and up to 600 times as much of the pollutant as producers? Responses A. POPs accumulate in the body fat of living organisms. POPs increase in concentration as they move up the food chain. B. POPs can travel over long distances by wind or water. Predators have greater access to different locations than do producers and therefore have higher concentrations of POPs. C. POPs are not carbon-based compounds, so animal digestive systems lack enzymes capable of breaking them down. POPs biomagnify in the fatty tissues of animals but not in plants. D. POPs are solids, which only animals can ingest. Therefore, POPs have a greater effect on secondary and tertiary levels of food chains.

A. POPs accumulate in the body fat of living organisms. POPs increase in concentration as they move up the food chain.

Based on the diagram, which of the following processes most likely caused the fish in the lake to die? A The remains of the bottom-dwelling plants and algae decomposed, depleting the amount of oxygen in the water. B The algal bloom at the surface released carbon dioxide into the water, suffocating the fish. C The herbicides used on the corn crop were washed into the lake, accidentally poisoning the fish. D Carbohydrates were released into the water when the bottom-dwelling plants died, increasing the amount of competition for food.

A. The remains of the bottom-dwelling plants and algae decomposed, depleting the amount of oxygen in the water.

Significant increases in water temperature can drastically change dissolved oxygen (DO) levels in a lake. Why does the combined effect of these two environmental changes result in algal blooms? Responses A.Low dissolved oxygen leads to death for aerobic organisms, like fish, whose decomposition provides an overabundance of nutrients for the algae, resulting in the large blooms. B. Increased temperature causes an increase in metabolic rates of fish and insects. Increased metabolism results in increased waste from aquatic organisms, which provides energy for the algae to grow rapidly. C. Increased temperature and low dissolved oxygen drive aquatic animals out of the area. The lack of competition gives the algae more nutrients for reproduction. D. Increased temperature leads to an increase in dissolved oxygen. The higher oxygen content increases the rates of cellular respiration and reproduction, resulting in an increased population of algae.

A.Low dissolved oxygen leads to death for aerobic organisms, like fish, whose decomposition provides an overabundance of nutrients for the algae, resulting in the large blooms.

One benefit of solid waste disposal in landfills is that the methane produced from decomposition can be harnessed for energy. Based on the data in the graph, methane production from waste management most likely peaked during which of the following years? A 1980 B 1990 C 2000 D 2010

B 1990

Which of the following approaches should be used to calculate the amount of lead, in milligrams, that would be present in a population of 200 rats with each rat weighing on average 20 grams, dosed with the LD50LD50 dose. A 200rats×20g1rat×1kg1000g×150mg1kg B 200rats×20g1rat×1kg1000g×100mg1kg C 200rats×20g1rat×1kg100mg×1000mg1kg D 200rats×1rat20g×1kg1000g×150mg1kg

B 200rats×20g1rat×1kg1000g×100mg1kg

Which of the following best describes the source of persistent organic pollutants (POPs) that could accumulate in the tissues of a top predator? A Methane (CH4) and carbon dioxide (CO2) released from livestock operations B DDT and other pesticides that are sprayed to control for mosquitoes C CFCs that are manufactured to be used as pesticides D Sulfur dioxide (SO2) released from coal-burning power plants

B DDT and other pesticides that are sprayed to control for mosquitoes

A scientist wants to study the effect of DDT in a fish-eating bird species. She measures a variety of variables in a population of birds over a period of ten years to determine how levels of DDT affect bird survival and reproduction. Which of the following identifies a scientific question she could ask to best evaluate the effect of DDT on the bird species? A Is the bird species able to metabolize DDT faster than the fish the birds consume? B Does the persistence of DDT lead to eggshell thinning or developmental deformities in the bird species? C Has the decrease in DDT usage led to a decrease in DDT concentration in the tissues of fish-eating birds? D How long does it take for DDT to break down once it is absorbed in the fatty tissues of the fish-eating birds?

B Does the persistence of DDT lead to eggshell thinning or developmental deformities in the bird species?

Based on the pathways shown in the diagram, which of the following best describes how climate change will most likely increase the transmission rates of the Zika virus? A A decrease in the number of baboons will lead to an increase in human exposure to the virus. B Expanded mosquito ranges will increase human exposure to the virus. C A shift in the human population to urban areas will decrease transmission between people. D Desertification will cause an increase in the number of monkeys and chimpanzees, which will decrease the overall number of cases of Zika.

B Expanded mosquito ranges will increase human exposure to the virus.

Based on the diagram, which of the following is the vector that transmits the Zika virus to humans? A Chimpanzees B Mosquitoes C Tree pollen D Urban areas

B Mosquitoes

According to the World Health Organization, persistent organic pollutants (POPs)(POPs) are found in nearly all tested organism tissues and environmental samples. Which characteristic of POPs accounts for their presence in living tissues and in environmental samples? A POPs are lipophilic, which means that they can be stored in fatty tissues for long periods of time. B POPs are released in to the air, water, and land, which allows them to be transported and incorporated in multiple ways. C POPs are synthetic chemicals, so only humans and urban environments are exposed to the pollutants. D POPs are organic compounds, so they can biodegrade easily and move through various environments.

B POPs are released in to the air, water, and land, which allows them to be transported and incorporated in multiple ways.

Based on the diagram, which of the following processes most likely caused the algal bloom in the lake? A The water table rose and caused widespread flooding in the area. B Runoff carried excess fertilizer from the cornfield into the water. C Excess oxygen was released into the water when the fish died. D Decomposition of the dead algae used up all the dissolved carbon dioxide.

B Runoff carried excess fertilizer from the cornfield into the water.

Which of the following would best be described as a point source of pollution from a farm? A Nitrogenous fertilizers added to drip irrigation used for growing crops B Runoff from the waste lagoons of Concentrated Animal Feeding Operations, which enters local waterways after a flooding event C Tractors and harvesters burning fossil fuels and releasing carbon dioxide and nitrous oxides into the atmosphere D Particulate matter from bare soil on plowed fields entering the atmosphere from wind

B Runoff from the waste lagoons of Concentrated Animal Feeding Operations, which enters local waterways after a flooding event

Which of the following statements best describes how the Clean Water Act legislation aims to protect wetlands from being lost? A The Clean Water Act bans the draining of wetlands over five acres in size. B The Clean Water Act requires wetlands to be constructed to mitigate the effect of newly drained wetlands. C The Clean Water Act establishes standards for the quality of surface waters that must be continually monitored and reported. D The Clean Water Act prohibits the use of wetlands for development and construction.

B The Clean Water Act requires wetlands to be constructed to mitigate the effect of newly drained wetlands.

Which of the following best describes why persistent organic pollutants (POPsPOPs) are toxic to organisms? A They emit gamma radiation, increasing the likelihood of mutations and cancer. B They do not break down easily and can accumulate in the fat tissue of an organism. C They are easily dispersed by wind and water, greatly increasing the affected areas. D They are naturally occurring in the soil and water; therefore, they easily contaminate the food web.

B They do not break down easily and can accumulate in the fat tissue of an organism.

The LD50 for arsenic in humans is 13mg/kg. Which of the following approaches should be used to calculate the number of grams of arsenic it would take to reach the LD50 in a 140-pound person? [Note: 1kg=2.2pounds] Responses A. 140lb×2.2lb1kg×1kg13mg×1g1,000mg B. 140lb×1kg2.2lb×13mg1kg×1g1,000mg C. 13mg1kg×50×140lb×1kg2.2lb D.13mg1kg×1kg2.2lb×140lb1

B. 140lb×1kg2.2lb×13mg1kg×1g1,000mg

A biologist is studying a small food web in which phytoplankton are eaten by krill, krill are eaten by fish, and fish are eaten by seals. During their study of the ecosystem, the biologist discovers that PCBs are present in measurable levels in the water and wants to examine how PCBs could vary in different trophic levels. Which of the following best identifies a testable hypothesis for the study? A Biomagnification will cause the phytoplankton outside the study area to have the highest amount of PCBs in their tissues. B Biomagnification will cause the seals to have the highest amount of PCBs in their tissues. C Bioaccumulation will cause the seals outside the study area to have the highest amount of PCBs in their tissues. D Bioaccumulation will cause the fish to have the highest amount of PCBs in their tissues.

B. Biomagnification will cause the seals to have the highest amount of PCBs in their tissues.

Which of the following water quality tests would best indicate if sewage from the wastewater treatment plant has contaminated the Moose River? Responses A. Dissolved oxygen measured at site A B. Fecal coliform measured at site B C. Nitrates measured at site C D. Temperature measured at site D

B. Fecal coliform measured at site B

Which of the following is a way to potentially eliminate one of the greatest threats to the world's mangrove wetlands? Responses A. Increase desalination to reduce the effects of prolonged drought in mangroves. B. Integrate ecologically sound shrimp aquacultural practices with mangrove management. C. Construct dams in mangroves to increase sediment load and decrease pollution. D. Employ irrigation methods to address potential desertification of mangrove habitats.

B. Integrate ecologically sound shrimp aquacultural practices with mangrove management.

A scientist is studying PCBsPCBs in tertiary consumers. She wants to determine if PCBsPCBs can be found in tertiary consumers even though these compounds were banned in the United States in the 1970s. Which of the following best identifies a testable hypothesis for the study? Responses A. PCBs are highly soluble in water, so it is unlikely that the compounds will be found in the liver or kidneys of tertiary consumers because the compounds have been banned. B. PCBs are persistent organic compounds that are fat-soluble, so they should be found in the fatty tissues of tertiary consumers even though the compounds have been banned for decades. C. PCBs have synergistic effects with other toxins in the environment and are broken down in water and soil, so most tertiary consumers are not directly exposed to them. D. PCBs are acutely toxic to most forms of life and quickly kill most organisms upon exposure; therefore, tertiary consumers today would be expected to have high levels of the compound in their tissues.

B. PCBs are persistent organic compounds that are fat-soluble, so they should be found in the fatty tissues of tertiary consumers even though the compounds have been banned for decades.

Which of the following practices would best help to protect against inland and coastal flooding in urban areas? Responses A. Regulating the use of pesticides and fertilizers in agriculture B. Preserving wetland and coastal mangrove habitats C. Increasing the capacity of the sewer lines so they can handle a larger volume of water D. Straightening stream channels to increase stream flow

B. Preserving wetland and coastal mangrove habitats

Scientists are interested in determining if selenium, from a nearby mine, magnifies in the tissues of fish living in a lake. Which of the following best describes a testable hypothesis for the study? Responses A. Tissue from fish in the lake will have a higher level of selenium than tissue from fish in a nearby lake. B. Selenium will be at a higher concentration in fish tissue than in the tissue of fish prey. C. Fish will have a higher concentration of selenium than mercury in their tissues. D. Selenium will be at a higher concentration in acid mine drainage than in fish tissues.

B. Selenium will be at a higher concentration in fish tissue than in the tissue of fish prey.

When water used to cool power plants during normal plant operations is released into adjacent waterways, which of the following is most likely to occur as a result? Responses A. Biodiversity of aquatic life in the adjacent waterways would decrease because the used coolant water is radioactive. B. The dissolved oxygen in the adjacent waterways would decrease because used coolant water is warm and leads to thermal pollution. C. Salinity in the adjacent waterways would increase because of dissolved solids in the used coolant water. D. Nutrient levels in the adjacent waterways would increase because of phosphorous in the used coolant water.

B. The dissolved oxygen in the adjacent waterways would decrease because used coolant water is warm and leads to thermal pollution.

A massive bluegill fish kill was observed in a lake near a power plant during the winter months. It was determined that the plant was releasing large amounts of hot water into the lake. Which of the following explains what likely caused the death of so many bluegills in the lake? Responses A.The increased water temperature caused dissolved oxygen levels to increase, leading to greater metabolic activity of catfish, which outcompeted the bluegill fish for resources. B. The influx of warmer water caused an unexpected increase in the metabolic rate of the bluegills, which led to increased physiological stress from limited resource availability. C. Rates of organic matter decomposition increased, which lead to an increase in dissolved oxygen and increased bacteria levels. D. Photosynthetic output of aquatic plants decreased because of the higher temperature, which lowered the amount of carbon dioxide available for bluegills to carry out cellular respiration.

B. The influx of warmer water caused an unexpected increase in the metabolic rate of the bluegills, which led to increased physiological stress from limited resource availability.

At what step in the diagram would the last solid waste be removed from the wastewater in the treatment plant? A A B B C C D D

C C

Which of the following best describes the action of endocrine disruptors in organisms? A Endocrine disruptors scar the lung tissue of animals, inducing respiratory difficulties. B Endocrine disruptors block the central nervous system of animals, leading to behavioral abnormalities. C Endocrine disruptors mimic naturally occurring hormones in animals, leading to developmental disorders. D Endocrine disruptors reduce primary productivity in plants, inducing a trophic cascade.

C Endocrine disruptors mimic naturally occurring hormones in animals, leading to developmental disorders.

A scientist is studying the correlation between air pollution and cardiovascular disease in humans. Which of the following measures would best show a link between air pollution and cardiovascular disease? A Mortality rates from cardiovascular disease in populations in different countries B Total number of emergency room visits by individuals with cardiovascular disease in urban areas compared to rural areas C Occurrences of emergency room visits by individuals with cardiovascular disease on days with a high air quality index value D Change in number of individuals with cardiovascular diseases over the past 50 years compared to levels of atmospheric carbon dioxide

C Occurrences of emergency room visits by individuals with cardiovascular disease on days with a high air quality index value

Which of the following correctly identifies an example of an endocrine disruptor and the effect it might have on the human body? A High levels of lead in drinking water could lead to neurological damage. B Exposure to radon in indoor air is linked to increased rates of lung cancer. C Phthalates in cosmetics and shampoos reduce fertility. D The bacterium E. coli found in vegetables causes abdominal cramping and vomiting.

C Phthalates in cosmetics and shampoos reduce fertility.

Based on the diagram, organic solids that have settled to the bottom of the treatment tanks in step BB are transferred to which of the following for further processing? A Screens B Filter beds C Sludge treatment tanks D Effluent discharge

C Sludge treatment tanks

Based on the diagram, which of the following processes most likely caused the bottom-dwelling plants in the lake to die? A The remnants of the corn crop were burned after the corn was harvested, decreasing the amount of dissolved oxygen in the water. B Toxins such as lead and mercury were released into the water when the fish died. C The algal bloom prevented sunlight from reaching the bottom-dwelling plants, which reduced the rates of photosynthesis. D Oxygen was released into the water when the algae died.

C The algal bloom prevented sunlight from reaching the bottom-dwelling plants, which reduced the rates of photosynthesis.

Which of the following describes the independent variable in the experiment? A The simulated field environment that housed the group of twenty mice B The respiratory output of each mouse C The different levels of ozone introduced into the environments D The use of female mice

C The different levels of ozone introduced into the environments

Which of the following best describes how thermal pollution from power plants can affect aquatic ecosystems? A Water injected into the ground during the hydraulic fracking process can seep into wells, causing methane contamination. B Warm water runoff that reaches lakes and ponds slows down the metabolic rate of aquatic animals, which decreases primary productivity. C Warm water discharged into rivers and streams decreases the oxygen content of the water, which reduces the number of fish species. D Wastewater from nuclear power plants contains radioisotopes and carbonic acid, which increase the rate of cancer in aquatic species.

C Warm water discharged into rivers and streams decreases the oxygen content of the water, which reduces the number of fish species.

A pesticide was applied to a population of roaches, and it was determined that the LD50 was 55mgkg. If the average mass of a roach was 0.02kg, which of the following approaches will determine the dose in mg per roach? Responses A. 55mg1kg×10.02kg B. 55mg1kg×50%×0.02kg C. 55mg1kg×0.02kg D. 0.02kg1×55mg1kg50%

C. 55mg1kg×0.02kg

Based on the diagram, which of the following is an expected consequence of runoff and sewage in an aquatic environment? A. Decreased oxygen levels in surface water as a result of a decrease in photosynthetic rates by algae B. Increased oxygen levels in bottom water from increased rates of cellular respiration in decomposers C. Decreased oxygen production by seaweed on the seafloor from an increase in turbidity D. Increased oxygen production by decomposition of dead fish and other aquatic organisms

C. Decreased oxygen production by seaweed on the seafloor from an increase in turbidity

Based on the diagram, which of the following best describes how a malfunctioning air compressor would affect the process of sewage treatment? Responses A. The oxygen concentration in the aeration tank would increase. B. The settling of large debris, such as wood, from the water would be prevented. C. Fewer bacteria would be available to absorb dissolved organics in the tank. D. The sludge pump would return activated sludge to the aeration tank at a slower pace.

C. Fewer bacteria would be available to absorb dissolved organics in the tank.

Mercury concentrations were measured in freshwater shrimp populations in two different ponds, one polluted with mercury and one unpolluted, with a similar food web in each pond. Which of the following best identifies the scientific question that would guide this investigation? Responses A. How do different species of shrimp excrete mercury from their bodies? B. How does the food web in a pond affect biomagnification of toxins? C. How much mercury accumulates in the tissues of freshwater shrimp living in a polluted pond? D. How much mercury is found in the tissues of shrimp predators in an unpolluted pond?

C. How much mercury accumulates in the tissues of freshwater shrimp living in a polluted pond?

Which of the following is a point source pollutant that would likely affect the ecosystem health of a coral reef? Responses A. Small pieces of plastic washed in by local currents B. Runoff of oil from nearby urban highway systems C. Oil released from the broken hull of a shipwrecked tanker D. Excess nutrients introduced by fertilization of farmland

C. Oil released from the broken hull of a shipwrecked tanker

Which of the following best describes a way that persistent organic pollutants (POPs) cause harm in the environment? Responses A. Persistent organic pollutants release carbon dioxide and methane into the atmosphere when buried for disposal. B. Persistent organic pollutants release radioactivity during decay. C. Persistent organic pollutants are soluble in fat, so they accumulate in an organisms' fatty tissues. D. Persistent organic pollutants have magnetic signatures that confuse birds during migration.

C. Persistent organic pollutants are soluble in fat, so they accumulate in an organisms' fatty tissues.

If all four of the bacteria species shown in the graph are equally likely to contaminate agricultural products at a dose of 102 CFU102⁢ CFU, regulating which of the following species would have the greatest effect in reducing the likelihood of illness in humans? Responses A. C. jejuni B. E. coli C. Salmonella sp . D. Newly discovered bacterium

C. Salmonella sp .

Based on the image, which of the following conclusions can best be drawn to describe the conditions in the Long Island Sound? Responses A. The sound has high levels of dissolved oxygen as a result of storm water runoff from urban areas. B. The sound has high levels of phosphorus and nitrogen from an increase in the number of producers. C. The sound has large numbers of phytoplankton blooms that are decomposing and consumed by respiring bacteria. D. The sound has high numbers of respiring fish populations and very low turbidity.

C. The sound has large numbers of phytoplankton blooms that are decomposing and consumed by respiring bacteria.

Which of the following claims about brine shrimp is best supported by the data in the table? A Brine shrimp generally hatch in 36 to 48 hours in warm temperatures. B The growth and survival of brine shrimp are optimal 72 hours after hatching. C There is more food available for brine shrimp when the water has a salt concentration of 20mg/100mL. D The optimal salinity for brine shrimp hatching is 30mg/100mL.

D The optimal salinity for brine shrimp hatching is 30mg/100mL.

Based on the data in the table, which of the following concentrations of sodium chloride is most toxic to brine shrimp? A 0mg100mL B 10mg100mL C 20mg100mL D 30mg100mL

D 30mg100mL

Based on the LD50LD50 data in the table, which of the following equations should be used to calculate how many times greater the resistance of a rabbit to xx-rays is than that of a dog? A 800−325 B 800+325 C 800×325 D 800/325

D 800/325

Which of the following should be added to the study to best serve as the control group? A A replicated experiment using male mice B A replicated experiment conducted in the field and not in the laboratory C A group of twenty mice provided with additional food resources D A group of twenty mice that were not exposed to ozone

D A group of twenty mice that were not exposed to ozone

At what step in the diagram would wastewater most likely be treated with chlorine or UV light to remove bacteria? A Before step A B Between steps A and B C Between steps C and D D During step D

D During step D

Based on the diagram, which of the following is one way that the Zika virus can be spread within the human population? A Airborne transmission B Through drinking water C Through contaminated food D From a mother to her unborn child

D From a mother to her unborn child

Based on the data in the graph, which of the following solutions most significantly contributed to the decrease in the amount of waste sent to landfills from 1990 to 2015 ? A Increased composting of domestic waste B Increased composting of e-waste C Increased combustion of waste D Increased recycling of waste

D Increased recycling of waste

Which of the following best explains why the die-off event occurred in the lake following the increased water temperature? A The warm water increased the amount of dissolved oxygen in the water, which led to an increase in the photosynthetic rate of the aquatic organisms. B The warm water increased the amount of dissolved oxygen in the water, which led to an increase in the amount of competition by consumers for food. C The warm water decreased the amount of dissolved oxygen in the water, which led to an increase in the rate of decomposition in the lake. D The warm water decreased the amount of dissolved oxygen in the water, which led to an increase in the respiration rate of the aquatic organisms.

D The warm water decreased the amount of dissolved oxygen in the water, which led to an increase in the respiration rate of the aquatic organisms.

Which of the following correctly identifies both a nonpoint source and a point source of pollution? D!!! Urban runoff and city bus exhaust

D!!! Urban runoff and city bus exhaust

Which of the following components, which are not shown on the diagram, are part of the tertiary treatment of wastewater? Responses A. Wet scrubbers B. Filters C. Coagulants D. Disinfectants

D. Disinfectants

Which of the following examples includes both a point and a nonpoint source of pollution? Responses A. A factory smokestack and a sewage overflow B. Runoff from city streets and pesticides from agricultural fields C. Waste from animal feedlots and sediment from construction sites D. Fertilizer from suburban lawns and wastewater from a water treatment plant

D. Fertilizer from suburban lawns and wastewater from a water treatment plant

Which of the following factors would most likely contribute to the conditions observed in the Long Island Sound? Responses A. Overfishing B. Plastic pollution C. Sewage treatment D. Restricted circulation

D. Restricted circulation

Some drinking water standards allow bacteria in water at dosages up to the 10% probability of illness. Which of the following statements is best supported by the data in the graph? Responses A. If there are fewer than 10^2 colonies for all species in a drinking water sample, the water will be considered safe to drink. B. If C. jejuni is the only species of bacteria present in the drinking water sample, the water will be considered safe to drink at all doses. C. E. coli and Salmonella s p p . would have the highest allowable dosage to meet the drinking water standards. D.The newly discovered bacterium would have the lowest allowable dosage to meet the drinking water standards.

D.The newly discovered bacterium would have the lowest allowable dosage to meet the drinking water standards.

Which of the following solutions would best address the issues of greatest concern in the community? Responses Construction of a seawall Planting mangrove forests Construction of an offshore breakwater Adding large sand dunes

Planting mangrove forests

Based on the diagram, which of the following is the most likely reason that a community with good sanitation could still have individuals who contract cholera? Responses Disease transmission for cholera is through direct contact with infected individuals and is independent of sanitation conditions. V. cholerae grow rapidly in clear, moving water that has limited nutrients or wastes. Waste water treatment facilities that use high levels of chlorine to treat the outgoing municipal water supply have an increased risk of cholera outbreaks. Runoff from a nearby agricultural field pollutes a reservoir used for drinking water.

Runoff from a nearby agricultural field pollutes a reservoir used for drinking water.

Based on the diagram above, which of the following best describes why a population in an area that has poor sanitation can be particularly at risk for a cholera outbreak? Responses V. cholerae is a parasitic bacterium often found in moving water, such as rivers and streams. Symptoms of the disease can appear anywhere from 2 hours to 5 days after initial ingestion of contaminated food or water. The bacterium that causes cholera is spread through ingestion of contaminated water or food. V. cholerae can survive in feces and aquatic environments for up to 2 months.

The bacterium that causes cholera is spread through ingestion of contaminated water or food.

Based on the diagram above, which of the following is the most likely reason that V. cholerae can spread rapidly through a population? Responses V. cholerae is a microscopic bacterium that can survive in various aquatic environments for prolonged periods of time and can cause a delayed onset of visible symptoms. V. cholerae is a macroscopic bacterium that is easily detected in aquatic environments and causes rapid onset of symptoms. V. cholerae eventually becomes airborne and is spread through the inhalation of spores, causing a delayed onset of visible symptoms. V. cholerae is transmitted via an insect vector and often goes undiagnosed in isolated communities.

V. cholerae is a microscopic bacterium that can survive in various aquatic environments for prolonged periods of time and can cause a delayed onset of visible symptoms.

The use of pesticides on crops has had significant negative effects on honeybee populations. The pesticide imidacloprid, which is used to control parasites like aphids, is highly toxic to bees in small concentrations. Imidacloprid has an LD50LD50 dose of 78ng78ng per bee, which weigh, on average, 0.1 grams. Which of the following approaches would you use to calculate the amount of pesticide, in milligrams per gram of bees? (Note: 1,000mg=1,000,000,000ng1,000mg=1,000,000,000ng) over 1,000,000

over 1,000,000