Environmental Engineering Reference
In-Depth Information
69.
B
Carbon monoxide binds to hemoglobin in red blood cells, blocking oxygen from binding with the
hemoglobin and, ultimately, depriving the cells and the body of oxygen.
70.
C
Crude oil is separated through boiling and distillation. In fact, the term
distillation
refers to the sep-
aration of the components of a substance through boiling. In oil distillation, components that boil at
high temperatures collect toward the bottom of a distillation column, while parts that boil at lower tem-
peratures rise and collect near the top.
71.
B
Fission is the reaction used in the process of generating nuclear energy. In a nuclear power plant,
heavy, unstable atoms are bombarded with neutrons, causing the nuclei to split. This split releases heat
as well as radiation in the form of additional neutrons, which cause other atoms to split, continuing the
reaction.
72.
C
Bioaccumulation occurs within an organism when it consumes other organisms containing a toxic-
ant, eventually concentrating the toxin in its body. In the situation described in this question, mercury is
the toxicant.
73.
A
A thermal inversion occurs when a layer of cool air is trapped beneath a layer of warm air. Usually,
air is warmed near the Earth's surface and, being less dense than cool air, travels upward, bringing with
it surface pollutants. In a thermal inversion, there is no convection current, thus no vertical mixing, so
pollutants remain trapped in the cool air near the Earth's surface.
74.
D
Both sulfur dioxide and nitrogen dioxide contribute to acid precipitation. Nitrogen dioxide (NO
2
) is
created from combustion processes at high temperatures, such as vehicle emissions. Once in the atmo-
sphere, NO
2
reacts to form nitrous and nitric acid, which are components of acid precipitation. Sulfur
dioxide (SO
2
) emissions are mainly due to the emissions from electric utilities that burn coal for energy.
SO
2
can react with water vapor to form sulfuric acid (H
2
SO
4
) and sulfate salts, which can cause acid
precipitation.
75.
B
Endocrine disruptors disturb the endocrine system (hormone system) by imitating hormones. The en-
docrine disruptors bind to receptor sites on cells, both blocking hormones from binding to these sites
and making the cell function as if a hormone is attached. This hormone displacement can lead to health
and reproductive issues.
76.
C
Chlorofluorocarbons (CFCs), which later were found to deplete the ozone layer, were emitted in ex-
tremely high amounts in the 1970s. In the atmosphere, a CFC molecule breaks apart, releasing a chlor-
ine atom. This atom of chlorine breaks apart an ozone molecule (O
3
) by ripping away one oxygen atom
to form chlorine monoxide (ClO) and leaving an oxygen molecule (O
2
). In 1987, the Montreal Protocol
was signed by over 150 nations, successfully cutting CFC production in half and allowing regeneration
of the ozone layer.
77.
D
Salvage logging is the removal of dead trees and brush after a wildfire. This dead vegetation could
serve as fuel for an additional fire. However, the environmental impacts of salvage logging include the
removal of nutrients from an ecosystem, the loss of habitat for other organisms, the acceleration of soil
erosion, and the resulting decrease in biodiversity.
78.
D
In a growing modern society, noise pollution has become an increasing issue. Some sources of noise
pollution are vehicle traffic, construction, and nightclubs. It is also a result of poor urban planning,
where housing may be too close to noise-pollution sources. Sailboats emit a very minimal amount of
sound, so they are not considered a source of noise pollution.
