Overall

Question 1

K-T boundary event

Answer 1

defines end of Mesozoic Era
Catastrophic impact by asteroid
-instantaneous mass extinction
-bye bye dinos

Question 2

5 Attitudes towards Environment

Answer 2

Technological fix: human ingenuity & science will be able to solve problems we run into
Evaluate and Respond: move forward based on the best available evidence
Gloom and doom: give up
Rosy Optimism: don’t worry, it will all work out
Frontier: resources are here for us to use and we’ll find others when needed (nature will provide solutions)

Question 3

How Societies Can Become More Sustainable

Answer 3

Natural ecosystems are a model of sustainability. They use energy and matter in ways that ensure those resources continue to be available.

Question 4

Three Social Traps

Answer 4

Tragedy of the Commons: each person acts in a way to maximize his/her own benefit (everyone ends up losing out)
Social Trap - Time Delay: an action produces a benefit today while deferring costs and problems for later (modern fishing techniques)
Sliding Reinforcer: an action that is beneficial at first may change conditions such that benefit declines

Question 5

Susan Solomon Hypothesis

Answer 5

Hypothesis – Cloud particles in the polar stratospheric clouds were providing surfaces for the reactions that would free chlorine molecules from CFCs. In sunlight, the chlorine molecules would then break up into isolated chlorine atoms that destroyed ozone.

Question 6

Synthetic toxins

Answer 6

Many are persistent; don’t degrade over time.

Question 7

Natural toxins

Answer 7

Natural doesn’t always mean safe! Consider arsenic in groundwater.

Question 8

Precautionary Principle

Answer 8

better safe than sorry

Question 9

How persistent is the substance?

Answer 9

Low persistence - Breaks down quickly with sunlight and oxidation etcHigh persistence - Long time to break down and potential environmental impact long after initial release

Question 10

How soluble is the substance?

Answer 10

Water and other liquids: May be safer for humans—excrete in urine Still potential toxic at high doses or continual low dose High impact on aquatic organisms—easy uptake Fat-soluble: Cross cell membrane in humans and harder to eliminate Some break down by liver Storage and accumulation in fatty tissue.

Question 11

Bioaccumulation

Answer 11

Fat-soluble substances build up in tissues of an organism over time

Question 12

Biomagnification

Answer 12

Higher on the food chain and able to consume the entire lifetime of toxins in their prey.

Question 13

Toxicology

Answer 13

Determining properties of toxins and their effects on cells and tissues.
Testing on animals - “in vivo” (in body)
Testing cells in petri dishes = in vitro (in glass)

Question 14

Additive effects
Antagonistic Effects
Synergistic Effects

Answer 14

Additive effects – Other chemicals may increase the effect of the toxin.
Antagonistic effects – Other chemicals reduce or cancel the toxin’s effects.
Synergistic effects – Chemicals increase the effects of the toxin, even beyond expectations.

Question 15

Endocrine Disruptors

Answer 15

interfere with the endocrine system (in which glands secrete regulatory hormones) They mimic a hormone or prevent a hormone from having an effect. BPA is an estrogen mimic.
- They can have one set of effects at a low dose and no effect or different effects at higher doses.

Question 16

Instrumental value

Answer 16

Ecosystems and species can have instrumental value (value as a tool) to people by providing ecosystem services. These can be quantified.

Question 17

Intrinsic Value

Answer 17

Ecosystems and species can also have intrinsic value, that is, value independent of any benefit accruing to humans. These cannot be quantified.

Question 18

Natural capital vs. natural interest

Answer 18

Natural capital – Consumable resources like air, water, trees, fish, and the systems that produce them
Natural interest – What is produced by the capital over time—more trees, fish, and oxygen.

Question 19

Mainstream economics and the triple bottom line

Answer 19

Mainstream economics does not account for all potential costs—costs associated with environmental stress.
Triple Bottom Line: Places value/cost on the external. Profit, Social, Environmental (or profit, people, planet)

Question 20

Linear Production Models and Closed-Loop systems

Answer 20

Linear production models assume that natural and human resources are infinite. We can either always get more or substitute for something else.
Closed-loop systems consider the life of a product, including its disposal throughout the production process.

Question 21

IPAT Model

Answer 21

The IPAT model used to estimate an ecological footprint for a population. Impact is a function of population, level of affluence, and level of technology.

Question 22

Zero Population Growth

Answer 22

occurs when the number or people being born is equal to the number dying—replacement fertility rate.

Question 23

Noncommunicable diseases

Answer 23

Can have a more significant impact but cannot be transferred from one individual to another.

Question 24

Infectious diseases

Answer 24

those that can move from one victim to the next by a vector or another organism. Many rely on other organisms as intermediate hosts.

Question 25

Three Types of Hazards

Answer 25

Biological hazards: these types of hazards include infectious agents (pathogens). Pathogens can be transmitted through vectors like insects and ticks, through direct person-to-person contact, and from contaminated food and water.
Chemical Hazards: includes environmental pollution and exposure to environmental pollution in the home or workplace, or that naturally occur in the environment. Largest contributor is smoke from burning solid fuels indoors and smoking.
Physical hazards: natural disasters, extreme weather events, exposure to uv rays, and even traffic accidents.

Question 26

Biosphere

Answer 26

the sum total of all of Earth’s ecosystems

Question 27

Ecosystem

Answer 27

all of the organisms in a given area plus the physical environment in which they interact.

Question 28

Habitat

Answer 28

the physical environment in which individuals of a particular species can be found.

Question 29

Biomes

Answer 29

one of many distinctive types of ecosystems determined by climate and identified by the predominant vegetation and organisms that have adapted to live there.
Biomes fall into three broad categories: Marine, freshwater, and terrestrial

Question 30

Niche

Answer 30

the role a species plays in its community, including how it gets its energy and nutrients, what habitat requirements it has, and what other species and parts of the ecosystem it interacts with.

Question 31

Nutrient cycle

Answer 31

Nutrient cycles: movement of life’s essential chemicals or nutrients through an ecosystem (also known as biogeochemical cycles).

Question 32

Carbon Cycle

Answer 32

Carbon Cycle: Carbon (as CO2) is released during cellular respiration and is returned to the atmosphere. Carbon (as CO2), is removed from the atmosphere during photosynthesis and is incorporated into plants, which use or store it; it is passed on to consumers via the food chain.
Cellular Respiration, Photosynthesis, Consumption, Decomposition

Question 33

Nitrogen Cycle

Answer 33

Nitrogen is the most abundant element in the Earth’s atmosphere and is needed to make proteins and nucleic acids.
Plants cannot use nitrogen directly from the atmosphere but, rather, must “fix” it into usable forms through the nitrogen cycle.
During nitrogen fixation, one form of nitrogen is converted by bacteria to another form that can be taken up by the roots of plants.

Nitrogen Cycle: N-fixation - microbes convert atmospheric N2 to NH3 and lightning converts N2 to NO3; both are forms of nitrogen that plants can use. Decomposing microbes break down the organic matter and release NH4. Different microbes use this NH3 and release NO3, another form of nitrogen that plants can use. Still other microbes use NO3 and convert it to N2, completing the cycle.

Question 34

Phosphorus Cycle

Answer 34

Phosphorus Cycle: Phosphorus is needed by all organisms to make DNA. This is a very slow cycle. There is no atmospheric component—it is dependent only on the weathering of rock to release new supplies into the water and soil. Once dissolved in water, the phosphorus can be taken up by organisms.
Phosphorus passes from inorganic to organic form through interaction with water and organisms.

Question 35

3 kinds of population distribution

Answer 35

Different kinds of Population Distributions:
Clumped Distribution: individuals are found in groups within the habitat
Random Distribution: species that disperse randomly in an environment like wind-blown seeds that germinate where they land.
Uniform Distribution: individuals spaced evenly possibly due to territorial behavior or something required for growth.

Question 36

J-Curve

Answer 36

J-Curve: mathematical models describe population growth over time.
Without environmental limits, a population will reach its maximum per capita rate of increase (r) , or biotic potential.
Increase in population is exponential with species exhibiting high biotic potential.
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Question 37

characteristics of r adapted species

Answer 37

Characteristics of r-adapted species:
Short life
Rapid growth of individual
Early maturity
Many, small  offspring
Little parental care
Adapted to unstable environment
High rate of population increase and well  adapted to exploit unpredictable environments. Will increase quickly as resources become available. 
Rapid reproductive potential sometimes have sudden population growth, commonly overshoot and crash

Question 38

S-Shaped Curve

Answer 38

S-Shaped Curve: population size increasing while the growth rate decreases
Exponential growth can’t last forever (resources become scarce, starve/unable to find habitat, competition increase, pressure from predation, etc.)
Carrying capacity (K): population size that can be sustained indefinitely without long-term damage to environment

Question 39

K adapted species characteristics

Answer 39

Characteristics of K-adapted Species:
Long life
Slower growth of individual
Late maturity
Few, large offspring
High parental care
Adapted to stable environment
Low reproductive rates and adapted to stable environmental conditions.
Decrease or increase slowly as resource availability changes.
K-selected species tend to be stable in undisturbed areas.

Question 40

Limiting vs. Resistance Factors; Density Dependent vs. density Indepedent

Answer 40

Limiting factors are resources needed for survival but that may be in short supply. This scarcity will determine carrying capacity.
Resistance factors, such as predation, competition, and disease, will also contribute to controlling population size and growth.

These factors are density-dependent, but other factors such as natural disaster are density-independent since they would occur regardless of the population size.
Effects of Density-dependent factors increase as populations grow (disease, competition, and predation).
Effects of density-independent factors affect a population, regardless of its size, but can serve to decrease the population (storm, fire/flood, avalanche).

Question 41

Ecosystem services

Answer 41

like pollination, water purification, and trapping contaminants.

Question 42

Ecotones and edge effects

Answer 42

Ecotones occur when two distinctive ecosystems meet.

The physical differences between the two areas create edge effects, which either attract or repel some species.

Question 43

Ecological succession

Answer 43

Ecological Succession occurs when conditions are dramatically changed.
Now species move into an area where they hadn’t been before and become established.

Question 44

3 Forest Biomes

Answer 44

Boreal Forest (Taiga): largest terrestrial biome, high elevations, low latitudes, short growing season, major trees are evergreens.
Temperate Forest: Distinct seasons, fertile soil, rich and diverse plant life, trees are mixed evergreens and deciduous.
Tropical Forest: Distinct seasons, less fertile soil, rich and diverse plant life, trees are mixed evergreens and deciduous.

Question 45

Maximum Sustainable Yield

Answer 45

Harvest only as much as can be sustainably produced or replaced.

Question 46

Multiple-Use Sustained-Yield Act

Answer 46

Mandates that national forests be managed to balance multiple (sometime conflicting) uses (1960)

Question 47

Forest Ecosystem Management (FEM)

Answer 47

Manage the ecosystem as a whole rather than focusing on just timber yields (present).

Question 48

4 major tree harvesting methods

Answer 48

Selective cutting: high value trees are cut, leaving others to reseed the plot.
Immediately after harvest: profits are intermediate between clear-cut and strip harvest levels. Land can be harvested again in less than 50 years. Biodiversity declines after harvest, but not as much as in clear-cut lands.
Clear-cutting: all trees are cut; replanted with a fast-growing species.
Immediately after harvest: High profits at harvest, then no profits as forest regrows. Water is polluted by heavy erosion on steep slopes. Biodiversity is very low after the cut.
Strip cutting: all trees are cut in a strip; here we show it replanted with one species but it may also be allowed to reseed from nearby trees.
Initially after harvest: profits are initially lower than for clear-cuts, but are more frequent. Biodiversity declines, but some organisms find refuge in uncut forests.
Seed tree/shelterwood: the best trees are left behind to reseed the plot.
Profits are similar to those of select harvest initially, but better than select harvest on subsequent cuts, since high-quality trees remain. Biodiversity declines after each harvest, but may be higher than select harvest levels.

Question 49

Ecological cascade

Answer 49

Plants die, soil erodes, prairies fail, famines can set in.

Question 50

Grasslands

Answer 50

Grasslands are biomes that receive enough rainfall to support grass and herbaceous plants, but not enough to support forests.

Question 51

Ocean acidification

Answer 51

CO2 enters the ocean from atmosphere; fossil fuel burning provides extra CO2, increasing the amount that ultimately enters. If more H+ is present (acid conditions), it binds to the Co3 needed to make shells. H+ causes shells to dissolve.