unit 8

Which of the following correctly identifies both a nonpoint source and a point source of pollution?

D -Urban runoff / City bus exhaust

A point-source of organic waste is discharged into a stream. Which of the following graphs best depicts the expected pattern for dissolved oxygen in this stream as a function of distance from the discharge point?

E

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?

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.

Put the events leading to cultural eutrophication in the correct order. W - leaching of nutrients from fertilized agricultural lands X - fish die-off Y - algal bloom

W->Y->X

Which of the following describes a component of a modern sanitary landfill?

a. A bottom liner of plastic or clay to prevent groundwater contamination

Which of the following is most likely to result from destruction of wetlands surrounding a river?

a. An increased frequency of flooding of the river valley

What gas is generated in a landfill and often recovered to provide a source of energy?

a. CH4

Mandates the restoration and maintenance of the chemical, physical, and biological integrity of the nation's waters

a. Clean Water Act

Which of the following is the most likely route for mercury to enter the food web?

a. Coal-burning emissions → deposition → ocean → plankton → fishes

Of the following, which is the most serious immediate problem associated with sanitary landfills?

a. Leachate contamination of groundwater

Which of the following strategies will best help to protect mangrove habitats?

a. Limiting coastal development and maintain a shoreline buffer zone

The processes described above are steps in the purification and treatment of municipal wastewater. The steps are listed in random order. Which of the following lists the steps in the correct sequence?

a. P -> S -> R -> Q

Based on the data table below for a stream in Illinois, which site most likely has a construction site immediately upstream from it?

a. Site C

A scientist wanted to investigate the effect of tropospheric ozone on the respiratory function of mice. Twenty female mice were placed in one of five different field environments that mimicked the natural habitats of the mice. Each environment had a tube connected to it that would pump in a set level of ozone measured in ppm. In each field environment, the scientist measured the average respiratory output for the twenty mice over a three-month time frame. Which of the following describes the independent variable in the experiment?

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

Critics of incineration of municipal solid waste suggests that it may not be the best solution for the future, for which of the following reasons?

a. incineration contributes to air pollution

Which of the following is a common characteristic of lakes undergoing cultural eutrophication?

a. increased levels of plant nutrients

of the following, which is the primary method of waste disposal in the United States?

a. landfilling

Which of the following is the greatest component (by weight) of municipal solid waste in the United States?

a. paper

The LD 50 of five chemicals are Isited below. Which is the most toxic?

b. 5 mg/kg body weight

At what step in the diagram would wastewater most likely be treated with chlorine or UV light to remove bacteria?

b. During step D

Which of the following examples includes both a point and a nonpoint source of pollution?

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

Which of the following best explains why top predators can have up to 60 times as much of persistent organic pollutant (POP) as their prey and up to 600 times as much of the pollutant as producers?

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

The release of a large amount of sewage and other organic wastes into a river would likely result in a sharp

b. increase in the biological oxygen demand

Dead zones, such as the one in the Gulf of Mexico that exists off the eonst of Loulsiana, are charneterized by all of the following EXCEPT

b. low nitrogen concentrations

Lakes that are characterized by high water clarity and low concentrations of dissolved nutrients are classified as

b. oligotrophic

Which of the following is an effective alternative to chlorine for disinfecting wastewater in a municipal treatment plant?

b. ozone

A scientist wanted to investigate the effect of tropospheric ozone on the respiratory function of mice. Twenty female mice were placed in one of five different field environments that mimicked the natural habitats of the mice. Each environment had a tube connected to it that would pump in a set level of ozone measured in ppm. In each field environment, the scientist measured the average respiratory output for the twenty mice over a three-month time frame. Which of the following should be added to the study to best serve as the control group?

c. A group of twenty mice that were not exposed to ozone

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

c. C

Which of the following federal laws specifically deals with the cleanup of abandoned hazardous waste sites?

c. Comprehensive Environmental Responsibility Compensation and Liability Act

Which of the following best describes the source of persistent organic pollutants (POPs) that could accumulate in the tissues of a top predator?

c. DDT and other pesticides that are sprayed to control for mosquitoes

The diagram below depicts a surface water source that has undergone cultural eutrophication. Based on the diagram, which of the following processes most likely caused the fish in the lake to die?

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

Which method introduces microorganisms to break down hazardous organic compounds?

c. biological treatment

Most plastics pose a special problem in the waste stream because they

c. decompose slowly, if at all, and persist as solid waste

Based on the graph above, what is the LD-50 of CuSO4?

d. 100 mg/kg

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?

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

The use of nitrogen-based fertilizers in the Midwestern United States is a major contributing factor to which of the following?

d. Hypoxia in the Gulf of Mexico

Which of the following are characteristics of methylmercury? I. Fat soluble II. It biomagnifies in food chain III. Low persistence in aquatic system

d. I and III only

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?

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

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?

d. endocrine disruptors

The toxin that poses a health risk to humans who eat large quantities of marine fish such as swordfish and tuna is

d. mercury

Which of the following laws gave the EPA the authority to control hazardous waste from "cradle-tograve". including the generation, transportation, treatment, storage, and disposal of hazardous waste?

e. Resource Conservation and Recovery Act (RCRA)