Final Exam Flashcards
toxicant
a toxic substance or poison that can be man-made or natural
toxicity
the degree of harm a chemical substance can inflict
toxins
toxic chemicals manufactured in the tissue of living organisms/naturally made in plants and animals
ex: snake venom
environmental toxicology
deals specifically with toxic substances that come from or are discharged in our environment
what are the four types of environmental hazards?
physical, chemical, biological, and cultural
physical hazards
arises from processes that occur naturally in our environment and pose risks to human life or health
ex: UV rays from the sun that cause skin cancer
chemical hazards
include many of the synthetic chemicals that humanity manufactures
ex: pharmaceuticals
biological hazards
result from ecological interactions among organisms
ex: mosquitoes causing diseases
cultural hazards
hazards that result from your place of residence, the circumstances of your socioeconomic status, you occupation, or your behavioral choices
ex: choosing to smoke cigarettes
what are hormones?
chemical messengers in the body that are produced in small quantities
how do hormones work?
receptors and hormones connect together which then tells the body to do a certain action
how can an endocrine disruptor disrupt the normal behavior of hormones?
endocrine disruptors mimic hormones when they connect to receptors and they then block and mimic those hormones
carcinogens
substances or types of radiation that cause cancer
mutagens
substances that cause genetic mutations in the DNA of organisms
- cause irreversible change in your DNA
teratogens
chemicals that cause harm to the unborn
- cause birth defects in the embryo
neurotoxins
chemical toxicants that assault the nervous system
ex: snake venoms, mercury, lead
allergens
over-activate the immune system, causing an immune response when one is not needed
endocrine disruptors
toxicants that interfere with the endocrine system
- affects and controls growth, development, sexual maturity, regulate brain function
examples of endocrine disruptors and their effects?
BPA- mimics estrogen and can interfere with basic bodily functions
Phthalates- cause males to become more feminine, females to become more manly, alters the development of genitals, and affects sperm count and quality
how do scientists understand the hazardous effects of toxicants?
- field observations
- natural tests
- manipulative experiments
LD 50
lethal dose- the amount of toxicant required to kill 50%of the subjects
ED 50
effective dose- the amount of toxicant required to effect 50% of the subjects
threshold dose
the smallest dose of radiation that will produce an effect
dose-response curve
it correlates the dose exposure with the changes in the human body/health that is then plotted on a graph
troposphere
bottommost atmospheric layer that blankets the Earth’s surface and provides us the air we breathe
- air pollutants hang out here
stratosphere
extends above the troposphere 11-50km above sea level and is more dry and more dense
- where the ozone layer is
air pollution
substance in the air that is poisonous or harmful
air pollutants
a material in the air that can have adverse effects on humans and the ecosystem
primary pollutants
pollutants released directly from a source, directly harmful, and can interact with other pollutants
ex: ash from a volcano, sulfur dioxide, carbon monoxide
secondary pollutants
the pollutants that form when primary pollutants react with one another and form these (secondary) pollutants
ex: ozone formed from pollutants from urban smog, sulfuric acid and nitric acid that form acid rain
what is residence time?
how long a pollutant stays in the atmosphere
stratospheric ozone depletion
the thinning of the ozone layer caused by the release of chemical compounds because of human activities and industries
what is the ozone hole?
when more than half of the ozone gas in a particular area is depleted causing harmful UV rays to pass through and reach Earth’s surface
causes and effects of ozone depletion
causes are CFCs
effects are suns UV rays come down and affect people on earth and cause skin cancer
when is the ozone hole the largest and over what regions?
springtime over the Arctic and Antarctica
what is the montreal protocol?
when 196 nations agreed to cut CFC production in half by 1998
when will the ozone hole recover and why will it take so long?
by 2070 because of the residence time of about 100 years for CFCs
how is acid rain caused?
the burning of fossil fuels which releases sulfur dioxide and nitric oxide. these then mix with water vapor in the atmosphere and turns it into sulfuric acid and nitric acid
effects of acid rain
plant mortality, leaches nutrients, runoff from acid rain hurts fish and plants
how did permit trading and cap and trade contribute to the reduction of acid rain?
the cap was the government did not allow companies to emit more sulfur into the air and the trade was that companies could buy and sell allowances that let them emit only a certain amount that one company did not already emit
why are some areas hit with acid rain worse than others?
because the wind blows the air pollution to certain areas causing more acid rain with greater damage
climate vs weather
weather is meteorological changes on a very localized scale and climate is global patterns over decades
what are the 3 factors that influence climate?
sun atmosphere oceans
what is global climate change
describes an array of changes in aspects of Earth’s climate like temperature and precipitation and frequency of storms
5 components of global climate change
sea levels, snow and ice cover, intensity and frequency of storms, precipitation, earth’s surface temperature
how is the greenhouse effect caused
caused by greenhouse gases which cause Earth’s surface temperature to rise. it traps the heat from the sun in the atmosphere
greenhouse gases and their sources
CO2- incinerators, burning fossil fuels, deforestation
methane-cows, landfills, burning fossil fuels
nitrous oxide- fertilizers, burning of fossil fuels
CFCs- aerosols, refrigeration
water vapor- natural component of atmosphere
what makes some greenhouse gases more potent than others
one may last longer in the atmosphere but others have a larger warming potential
which of the five gases occurs in the highest concentration
water vapor
what is radiative forcing
it measures the impact of each greenhouse gas on earth’s surface temperature
what factors contribute to positive radiative forcing
warms the surface
what factors contribute to negative radiative forcing
cools the surface
how do researchers study climate change
ice cores, tree rings, and sediment cores from lakes
scientific evidence for global climate change
past: ice cores, sediment cores from lakes, tree rings
present: plants are blooming earlier in the season, amount of CO2 we see now is so high it has never been recorded to be this high ever
what are proxy indicators
indirect evidence that substitutes for direct evidence
proxy indicators that are used to look at the climate in the past
ice cores
sediment cores from lakes
tree rings
coral reefs
whats the IPCC
intergovernmental panel on climate change that has scientists and government workers on a panel that observes current trends, gives predictions of future impacts, and lists strategies to pursue
current and future impacts of global climate change
plants are blooming earlier in the season
bird populations are going down because of lack of food during mating season
food availability may decrease
affect human health because of air quality
what are the impacts of global climate change on biodiversity including those on corals?
the water catches the CO2 which causes the water to become acidic and it then bleaches and kills the coral–>which destroys the homes and food for many fisheries and marine life
what are the other explanations for climate change?
Milankovitch cycles state that changes in earth’s rotation may trigger climate variation
variation in solar output states that energy from the sun decreased slightly
mitigation to global climate change
reduce the effects of climate change by lowering emissions, switching to renewable energy, reducing deforestation, and more
adapting to global climate change
sea walls, restricting coastal development, modifying agricultural practices to cope with less water, and migrations (environmental refugees)
sources that can make the biggest contributions to lowering greenhouse gas emissions
energy
transportation
agriculture
direct use value
the economic or social value of the goods derived from the services provided by an ecosystem that are used directly
includes consumptive values (harvesting goods) and non-consumptive values (enjoying scenic beauty)
indirect use value
derived from goods and or services that are not directly consumed or sold, yet beneficial. ecosystem services are indirect use value, like carbon sequestration by forests
option value
value in the future
bequest value
the legacy you want to leave
existence value
the value people are willing to pay to prevent a species such as the polar bear from going extinct
ecological footprint
impact of a person or community on the environment that is expressed as the amount of land required to sustain their use of natural resources
what is sustainability
a guiding principle of environmental science entailing conserving resources for the future
sustainable development
when we satisfy our current needs without compromising the availability of future resources
what is tragedy of the commons
a situation where the individual (acting out of self-interest) behaves contrary to the common good by depleting the shared resource through their collective action
tragedy of the commons and an in class example
fisheries on the east coast are now protected because they were overharvested
what is meant by market failure in an environmental context
it is the failure of markets to take into account the environment’s positive effects on the economy
what are external costs
a cost borne by someone not involved in an economic transaction. example: harm to people because of air pollution an industry discharges that is in their backyard
anthropocentrism
everything is based around humans, intrinsic value but utilitarian view
biocentrism
humans and other species have the right to exist and be protected
ecocentrism
importance is given to the ecosystem as a whole
what are some best management practices from our rescue mission lab
keeping the native plants–> form of pest control
hydroponics–> reduces runoff and fertilizer use
chicken coop–> use waste for composting
steps of the scientific process
observations questions hypothesis predictions test results
hypothesis
a proposed explanation made on the basis of limited evidence as a starting point for further investigation
prediction
a specific statement derived from a hypothesis (if, then)
theory
a broad explanation based on a large body of evidence that has withstood repeated testing
(THE MOST CERTAIN)
variable
in an experiment, a condition that can change
independent variable
(x axis) the variable the experimenter changes
dependent variable
(y axis) the variable we measure (response to the independent variable)
quantitative data
measured by the quantity of something rather than the quality
standardized variable
always the same
control group
the group that is not being tested on
experimental group
the group that is being manipulated
manipulative experiments
have a control and a manipulated group
natural experiments
occur in nature and are observatory experiments
what does the STANDARD ERROR OF THE MEAN give
tells you how far your sample mean deviates from the actual population mean
(the larger the sample size the smaller the SEM)
what doe STANDARD DEVIATION give
a statistic that measures the dispersion of a dataset relative to its mean
what does the P VALUE give
the probability of obtaining the observed results of a test assuming that the null hypothesis is correct
it determines significance
(THE LOWER THE P VALUE THE MORE LIKELY THE HYPOTHESIS IS TRUE)
what is not a source of methane
synthetic fertilizers
what is not a component of global climate change
depletion of the ozone hole
toxicants such as atrazine and BPA:
show unconventional dose-response curves
affect reproduction, development, and growth
alter levels of estrogen and testosterone in animals
what is the green new deal?
a deal that has the environmental goals of: clean and renewable energy, zero carbon emissions, and updated infrastructure (transportation, power grids)
what happens to plastic bags when they are recycled by target and Walmart?
ultra-low sulfur diesel
