apes unit 8

The table below shows the number of brine shrimp that hatched over 72 hours in three different concentrations of salt water. All tanks had 50 eggs at the start of the study. Based on the data in the table, which of the following concentrations of sodium chloride is most toxic to brine shrimp?

0mg/100mL.

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?

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 LD50 dose.

200rats × 20g/1rat × 1kg/1000g × 100mg/1kg

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 LD50 dose of 78ng 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 = 1,000,000,000ng)

78ng/bee × 1bee/0.1g × 1mg/1,000,000ng

The graph below shows the dose response curves for four different chemicals, labeled A — D, in a dose-response study on the effects of the chemicals on mortality in amphibians. All dose experiments began at 0 units of each chemical. Based on the data in the graph, which of the four chemicals is the most toxic to amphibians regardless of dose?

A

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?

A group of twenty mice that were not exposed to ozone

Which of the following is an example of a point source of pollution?

A leaking septic tank

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?

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

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

C: filter beds or activated sludge

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

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?

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

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

During step D

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?

Endocrine disruptors

Which of the following best describes the action of endocrine disruptors in organisms?

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

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?

Expanded mosquito ranges will increase human exposure to the virus.

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?

Fewer natural resources needed to be extracted.

Based on the data in the graph, which of the following solutions most likely led to the decrease in the amount of waste sent to landfills from 1990 to 2015 ?

Increased recycling of waste

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

Limiting coastal development and maintain a shoreline buffer zone

Based on the diagram, which of the following is the vector that transmits the Zika virus to humans?

Mosquitoes

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?

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

According to the World Health Organization, persistent organic pollutants (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?

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

Which of the following correctly identifies an example of an endocrine disruptor and the effect it might have on the human body?

Phthalates in cosmetics and shampoos reduce fertility.

Which of the following would best be described as a point source of pollution from a farm?

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

Based on the diagram, organic solids that have settled to the bottom of the treatment tanks in step B are transferred to which of the following for further processing?

Sludge treatment tanks

Which of the following statements best describes how the Clean Water Act legislation aims to protect wetlands from being lost?

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

Based on the diagram, which of the following processes most likely caused the bottom-dwelling plants in the lake to die?

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

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?

The different levels of ozone introduced into the environments

The table below shows the number of brine shrimp that hatched over 72 hours in three different concentrations of salt water. All tanks had 50 eggs at the start of the study. Which of the following claims about brine shrimp is best supported by the data in the table?

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

Based on the diagram, which of the following processes most likely caused the fish in the lake to die?

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

A small lake, located downstream of a power plant, recently experienced a die-off of multiple aquatic species. Environmentalists had been monitoring the temperature of the lake for several months prior to the die-off and noticed a significant spike in the temperature of the lake immediately preceding the die-off event. Which of the following best explains why the die-off event occurred in the lake following the increased water temperature?

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 best describes why persistent organic pollutants (POPs) are toxic to organisms?

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

Which of the following best describes how thermal pollution from power plants can affect aquatic ecosystems?

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

A scientist investigated the radiation sensitivity of different mammals to xx-rays to determine the LD50 within 30 days. Results from the study are included below. Based on the LD50 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?

800/325

Which of the following approaches would best decrease the impact of frequent flooding in a community that is subject to the hazard of flooding?

Construct wetland areas near the rivers and streams.

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

D: Urban runoff; City bus exhaust

Which of the following is the most likely impact of thermal pollution from power plants on a river ecosystem?

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?

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

Based on the diagram, which of the following is one way that the Zika virus can be spread within the human population?

From a mother to her unborn child

Based on the diagram, which of the following processes most likely caused the algal bloom in the lake?

Runoff carried excess fertilizer from the cornfield into the water.