Practice Exam 2 - Environmental Science - page 273

80. D During the planet's current climate alteration, glaciers are retreating rather than advancing due to
warming temperatures. As the glaciers retreat, the species that depend on them for survival are
threatened and face potential endangerment or extinction.
81. B Recombinant DNA technology combines DNA from different organisms, usually with the goal of
producing desired traits in a new genetically modified organism (GMO).
82. C Upwellings in the oceans carry nutrients from the ocean bottom to the surface, creating areas of high
primary productivity.
83. C As a result of the process of mining, the environment can be harmed in many ways, and the destruc-
tion varies depending on the type of mining employed. In general, though, mining can lead to the re-
moval of vegetation, acid drainage, and the production of toxic waste and runoff.
84. A The IPAT model examines the human impact on the environment due to population, affluence, and
technological innovations. Higher population means more resources consumed. Increased affluence res-
ults in the population's ability to consume more resources and, therefore, create more waste. Technolo-
gical innovations can either help the environment with advancements or create new ways to pollute and
deplete resources.
85. A The civilization on Easter Island overused its resources, using trees unsustainably. This led to the
downfall of the island's civilization. If modern society is not careful, resources may be overused to the
point where they cannot be replenished.
86. B Soil degradation is a positive feedback loop because depleted soil leads to an increasing pace of de-
gradation.
87. C Family planning is an essential tool in reducing population growth and includes the availability of
contraceptives, the empowerment of females in decision-making, and improved reproductive healthcare
options for women. The key component in any family-planning initiative is education, providing in-
formation to women and families.
88. B China currently has approximately 1.3 billion people, while India has 1.1 billion, and the United
States has about 300 million.
89. D Compaction reduces space between soil particles, obstructing the flow of gases, nutrients, and water
through the soil. It also can increase the amount of water runoff and, thus, erosion. Soils can be com-
pacted as a result of many factors, including the weight of grazing animals and the weight of heavy
equipment.
90. A Usually upwellings from the Humboldt Current in the Pacific Ocean bring nutrient-rich cooler wa-
ters up from the ocean bottom. During El Niño periods, the surface waters are warmer and upwellings
are reduced, limiting the amount of nutrients at the ocean's surface. This affects the productivity of the
ocean's fisheries, which, in turn, reduces the catch for fishermen and, thus, negatively impacts their in-
come.
91. E Decomposition usually requires oxygen. When extensive decomposition occurs in aquatic environ-
ments, a great deal of oxygen is consumed. This can deplete the area of oxygen, making it hypoxic.
92. C Carbon monoxide, methane, and nitrous oxide are all produced as a result of fossil fuel combustion.
When fossil fuel use increased in the past few centuries, so did resulting emissions.
93. B An increase in the amount of greenhouse gases in the atmosphere increases the amount of heat in the
atmosphere, potentially altering the world's weather and climate patterns. In some situations, more
severe weather events can occur.