Environmental Science Exam Key Terms Flashcards
What is the environment?
The sum of the surrounding conditions that influence life, health and growth
What is Environmental Science?
The study of interactions between human systems and natural systems.
What is a system?
A set of interacting components that influence one another by changing energy/matter.
Human Systems - Trains, highways
Natural Systems - Ecosystems
What is an Environmental indicator?
Tools of measurement to determine the health and quality of natural systems
*Measure human population, biodiversity, global temperature, CO2 levels
What is Biodiversity?
The variety of life in an ecosystem.
What are the 3 Levels of Biodiversity?
- Species diversity - # of species in an area or type of habitat
- Genetic diversity - Measure of genetic variation (higher the better)
- Ecosystem diversity - Diversity of ecosystems or habitats in an area
What is a Species?
Organisms distinct from other organisms in morphology, behavior, etc.
What is Food Production?
The ability to grow food for humans
*Healthy soils support food production
*Technology (irrigation, fertilization, genetic modification)
*Weather
(more grain used for livestock than humans!)
What is CO2’s Impact on Global Temperatures?
Greenhouse gasses like CO2 act as blanket to trap heat near Earth’s surface causing climate change.
Climate change is Anthropogenic (human based) from fossil fuels and net loss of forests.
*Last 200 years CO2 has increased in atmosphere and rising
What are some Dangers of CO2 Emissions?
Extreme heat, difficulty breathing, rising water levels, stresses circulator systems
Resource Depletion Examples
Land degradation from mining, waste and landfill pollution, air pollution, non-renewables.
What is the 1st Law of Thermodynamics?
Energy is neither created nor destroyed
What is the 2nd Law of Thermodynamics?
When energy is transformed, the quantity of energy remains the same, but its ability to do work diminishes. Energy forms are transformed into heat (Thermal Energy).
How Does Thermodynamics Govern the Life of Living Organisms?
Thermodynamics allows for energy to transfer between ecosystems and trophic levels. It is what makes up for an ecological balance that keeps our ecosystems running.
Where do Ecosystems Get Their Energy?
Most all of it is from the sun (photosynthesis), other organisms may produce energy in chemosynthesis on hot springs an sea floors
What are 3 Types of Consumers in a Trophic System?
- Primary Consumers - Herbivores that eat producers (plants)
- Secondary Consumers - Carnivores that eat primary consumers
- Tertiary Consumers - Rare, eat secondary consumers
What are Trophic Levels?
Organism’s levels of feeding and acquiring energy within a food web.
What are Some other Trophic Positions than the 3 Big Ones?
Omnivores - Eat plants and animals.
Scavengers - “Carnivores” that eat dead organisms.
Detrivores - Animals that consume dead plant material
Decomposers - Complete breakdown process and recycle nutrients
What is the Ten Percent Law?
10 percent law of energy flow states that when the energy is passed on from one trophic level to another, only 10 percent of the energy is passed on to the next trophic level.
What is Ecological Efficiency?
Percentage of energy transferred from one trophic level to another in a food chain or web, usually around just 10% each level
What are the 4 Chemical Reservoirs of Earth?
- Atmosphere
- Lithosphere
- Biosphere
- Hydrosphere
What is Carbon?
4th most abundant element in universe, found in all organic matters. Photosynthesis removes C from atmosphere, is returned in the form of CO2 or Methane (CH4). Can enter atmosphere through respiration, forrest fires, diffusion, and decomposition.
What is Carbon - Methane?
Potent greenhouse gas 21 times more powerful than CO2. Mostly occurs naturally through respiration, but can also be a product of fermentation and human activities.
What are the Causes of Unequal Earth Heating?
- Solar energy’s angle - Less atmosphere to travel to at equator vs. poles
- Surface area impacted - More concentrated at equator
- Albedo % - % incoming light reflected by surface (snow, water, etc)
How Does Earth Air Circulate?
Warm air is less dense than cold air, causing warm air to rise. Warm air has higher water vapor capacity, causing warm days to be more humid.
What is Climate Change?
Increase in average temperature due to greenhouse gasses keeping heat close to the Earth’s surface.
What are some Examples of the Effects Climate Change?
Has caused sea levels to rise 3 inches, glaciers shrinking, trees flowering sooner, coral reef destruction, and overall increase of 2 degrees F.
What is Evolution?
Change in the genetic composition of a population over time.
What are the 3 Processes that Drive Evolution?
- Artificial Selection - Human’s breeding of useful traits from the natural variation among different organisms
- Natural Selection - A natural process resulting in the evolution of organisms best adapted to the environment.
- Random Processes
- Mutation
- Genetic Drift
- Bottleneck Effect: When pops reduced, genetic variation reduced
- Founder Effect: Few colonizers give rise to new population
What is Population Ecology?
Study of dynamics within a population (grow/shrink?)
What are the Levels of Complexity (Population Ecology)?
- Individual
- Population (All individuals of same species in given area)
- Community (All populations within a given area)
- Ecosystem (All biotic and abiotic components of area)
- Biosphere (Biomes)
What are the 5 Population Characteristics?
- Population size
- Population density (# in given area)
- Population distribution (clumped/even?)
- Population sex ratio
- Population age structure (determines speed of growth)
What is a Niche?
Each species’ unique way of obtaining a limiting resource
What is Lieberg’s Law of the Minimum?
What ever resource is in lowest supply relative to its demand will limit the expanse of a population
What is Resource Partitioning and Its Types?
- Temporal - Being active at different periods of time
ex: Wolves and Coyotes
- Spacial - Using different areas of a system
ex: Fish and Wolves
- Morphological - Differences in body or shape to consume different types of resources
ex: Darwin’s Finches
What are Some Types of defenses against predation?
- Behavioral - playing dead when seen
- Morphological - camouflage or prickles
- Chemical - toxic or distasteful
- Mimicry - mimicking different organism
What are the Types of Symbiotic Relationships?
- Mutualism - benefits both species
ex: humans and dogs
- Commensalism - benefits one species while the other is neither harmed nor helped
ex: fish hiding behind coral
- Parasitism - benefits one species at the detriment of the other
ex: tape worms
What is Ecological Succession and its Types?
Ecological Succession - Process by which species and habitat changes over time
- Primary Succession - Occurs on surface devoid of soil (lava, glaciers)
- Secondary Succession - Disturbed areas that have not lost soil (forrest fire, post hurricane)
What Did Thomas Malthus Conclude?
Human population was growing exponentially while food growth was linear. (Alternate view is that innovation could alter Earth’s carrying capacity)
What are Convection Cycles?
Outer core’s high temp causes magma to move in convection cells under crust. Also occurs with radioactive decay of elements (potassium, uranium)
What is the Theory of Plate Tectonics?
Earth’s lithosphere is divided into plates, most of which are in constant motion as a result of magma movement in the outer core
*What Causes Earth’s Plates to Move?
All plate movement is driven by convection cells beneath the surface (move 1.4 inches yearly)
What is a Rock Cycle?
Constant formation and destruction of rocks. All rocks come from deposited material and eventually become sub-ducted turning into magma
What is an Igneous Rock? How are they Formed?
Formed directly from magma
- Intrusive Igneous: when magma rises and cools in place underground
- Extrusive Igneous: when magma cools above Earth’s surface by volcano or seafloor spreading
Basaltic Rock - dark, high in iron, dominant in ocean plates
Granitic Rock - light color, high in mica and quartz, dominant rock of continental plates
What is a Sedimentary Rock? How are they Formed?
Formed when mud, sand, or gravel fused together over long time
- Sandstone: made from compressed sand
- Conglomerate: mixed cobbles, gravel, and sand
*What is a Metamorphic Rock? How are they Formed?
When sedimentary, igneous, or other rocks are subjected to high temperature and pressure
ex: slate or marble
What is a Soil Cycle?
Mix of geologic and organic components that connect overlaying biology with underlaying geology
What is Groundwater’s Function? Water Table? Groundwater Recharge? Artisan Wells?
Allows plants to get water through roots and provides water to springs
Water Table - uppermost level at which water is fully saturated in rock or soil
Groundwater Recharge - when rain water or surface water pores through soil into an aquifer at a “recharge area”
Artisan Wells - pressure of overlaying rock pushes water to surface
What are the Consequences of High Water Withdrawl?
- Spring fed streams may dry up
- Shallow wells no longer reach water table
- *Cone of depression: water table near well is deeper than others
- *Saltwater intrusion: adjacent saltwater fills fresh groundwater
What is a Floodplain? How can it be Formed?
Lakes surrounding rivers
*Formed 2 ways
- Tectonic: formed by land
- Glaciers: large depression of land
What are Wetland’s Functions
- Absorb water to help prevent floods
- Clean and purify water
- Food (rice feeds half of worlds pop.)
- Shoreline and storm protection
- Cultural (hunting, fishing, and sightseeing)
- Habitat (contain 40% of planets species and 12% of animal species
- Nursery for important finfish and shellfish
- Migratory birds stay as well
What is Non-Renewable Energy?
Used once and cannot be replaced
*Includes:
- Fossil fuels (coal, petroleum), nuclear energy, and natural gas
What is Energy Efficiency?
Some energy forms better suited for certain jobs
*EROEI - energy return on energy invested
What is Electricity?
*Secondary source of energy
Produced from coal, oil, and natural gas
What is Coal Energy? What are the Pros/Cons/Byproducts?
*Most common electricity source
Made from remains of trees, ferns, and plants from 280 to 360 million years ago
Generation:
Steam energy turns blade of turbine
- Combined cycle: uses natural gas along with coal (gas combustion turns 2 turbines which turn generators)
*35% efficient
Pros: reliable, large global reserves, inexpensive
Cons: CO2 pollution, dangerous for miners, destroys natural habitats, not very efficient
Byproduct: ash, pollution
What is Petroleum Energy? How is it Produced? What are some Pros/Cons/Byproducts?
*Used for mobile combustion engines
Formed from remains of phytoplankton 50 to 100 million years ago. Common in areas where wedged between porous and nonporous rock
Pros: Relatively dense and cleaner than coal (85% emissions), good for combustion engines
Cons: CO2 pollution, can cause spills
Byproduct: pollution, oil spills
What is Natural Gas? How is it Produced? What are some Pros/Cons/Byproducts?
Fossil energy source found beneath Earth’s surface.
Generated by hydraulic fracking
- 80 to 95% methane
- Used for electricity and industry
Pros: Has fewer impurities than coal
Cons: 25x as potent as greenhouse gas, can cause explosions
Byproduct: heavy pollution, explosions
What is Nuclear Energy? How is it Produced? What are its Pros/Cons/Byproducts?
Energy captured from nuclear reactions
Uses heat from nuclear fission (neutrons strike each other) to turn steam turbines. Control rods absorb extra neutrons in the form of plutonium preventing meltdown
Pros: no CO2 Released, highly efficient, good for countries independent from oil, cost effective
Cons: can cause meltdowns, creates radioactive waste, uranium mining is dangerous
Byproduct: nuclear waste, some pollution during mining process
What Biomass (energy)? Provide The Examples
Derived from nature (wood, charcoal, manure, plant remains)
Wood - Used by 3 billion people for heating and cooling. Can use more timber than what naturally grows back
Charcoal - Made from “half burned” wood. Lighter and contains 2x as much energy as wood and produces less smoke
Dried Animal Manure - Used where wood is low, releases pollutants
Ethanol (Liquid Biomass) - Starches and sugars converted to alcohol and CO2. US 90% comes from corn. Can be mixed with gasoline to make “gasohol.” Some areas have E-85 Ethanol. Less energy than gasoline
Biodiesel: Usually B-20 (20% biomass). Comes from mostly soy beans
What is Geothermal Energy and how is it Produced?
*Uses heat from radioactive decay of underground elements
*Circulates cool liquid underground to be heated
Can be used for electricity, heating water to steam
Ground source Heat Pump - Uses ground’s retainment of sun’s energy
What is Hydroelectricity? How is it Captured? (examples too) What are its Pros/Cons?
(2nd most common renewable in US)
*Generated by energy of moving water
Examples:
Run of River - Common, retained by small dam and usually low electricity produced
Water Impoundment - Storing large amounts of water in reservoir behind dam
Tidal Energy - Attempts to obtain energy from tide shift. Not very efficient
Pros:
- Does not create air pollution
- Cheaper than natural gas/nuclear
- Controls floods
Cons:
- River must be help back
- People possibly forced to relocate
- Loss of organisms
- More disease abundant in impound waters
- Reservoir slowly fills with sediment
What is Solar Energy? How is it Captured? (examples too) What are its Pros/Cons?
*Capturing energy from sun
Examples:
Passive Solar Energy - Natural heating, cooking eggs on floor
Active Solar Energy - Capturing sun’s energy and using it different ways
Photovoltaic Systems - Low voltage electricity generated by capturing 12-20% of heat
Concentrating Solar Power Plants - Best in deserts, use lens to concentrate sunlight to produce steam-powered turbine
Pros:
- No pollution or CO2
- May be cheap
Cons:
- May be expensive
- Hard to install
- May require batteries
What is Wind Energy? How is it Captured? (examples too) What are its Pros/Cons?
*Result of energy produced by unequal Earth heating
*High EROEI
(US is largest producer)
Examples: Modern (350 ft tall, can supply 400 homes), Offshore (even larger)
Pros:
- No pollution
- Can share land
Cons:
- Needs batteries
- Produces noise
- 40,000 birds killed each year
What are Hydrogen Fuel Cells? Process? Pros? Cons?
*Electricity generated by reacting hydrogen and water
Protons forced through a membraned while electrons move in different direction generating electric current
*Car can be hydrogen fueled
Pros:
- 80% efficient
- Byproduct is water
Cons:
- Requires energy to produce
- Hydrogen can explode
How does Health Care Impact Disease?
*90% of diseases occur in developing nations where 10% of health care is spent
*2% of people with AIDS have access to modern medicine
How Can Chemical Resistance Impact Disease?
*Natural Selection allows organisms to evolve quickly
Malaria was nearly wiped out, but protozoans became resistant to antibiotics
Mosquitos are now resistant to insecticides
Feedlots can use a lot of antibiotics and hormones
What is Toxicology?
*The study of toxins (poisons) and their effect on living systems
What are the 5 Classifications of Toxicology?
(PUT ON NOTECARD)
- Neurotoxins - Attack nerves
- Heavy metals (lead, mercury) can kill nerve cells permanently
- Anesthetics (chloroform) disrupt functions
- Mutagens - Chemicals/radiation that damages DNA
- Can cause birth defects, tumors, changes in reproduction
- Teratogens - Chemicals that disrupt embryonic development
- ex: fetal alcohol syndrome can cause facial abnormalities, developmental decays, behavioral and mental deficits
- Carcinogens - Substances that cause cancer (out of control cell-division)
- 2nd leading killer in US
- 50% of men and 30% of women get cancer in their lifetimes
- Endocrine Hormone Disruptors (EDCs)
- Chemicals that disrupt hormone/gland function
- DDT and PCB interfere with growth
- Environmental estrogen/androgen can cause heath problems
What are the Ways to Measure Toxicology?
- Animal Testing (mice, rats, primates)
- Computer Simulations
- Cell Cultures
- LD50 - Lethal dose for 50% of tested group
