Environmental Science Exam General Terms Flashcards
What are Abiotic Factors?
Non-living Things: Air, light, temperature, etc.
What are Biotic Factors?
Living Things: Trees, plants, bacteria, animals, etc.
What is Science?
A process that produces knowledge involving the Scientific Method.
What are the Scientific Method Steps?
- Observation - Brings about questions
- Hypothesis - Testable statement
- Collect Data (through experiments)
- Interpret Results and reject/support hypothesis (reject or fail hypothesis)
What is a Theory?
A hypothesis that has been tested with a significant amount of data
What is a Scientific Law?
A scientific law takes a broad view of numerous observations, but never exactly explaining ‘why’.
What is Matter?
Anything that has mass and takes up space (Measured in grams).
Weight - force from gravity (N)
Mass - Quantity of matter regardless of gravity (g)
What is an Atom?
The smallest particle of an element
What is a Molecule?
A group of atoms bonded together. Electrons (negative) on outside, with protons (positive) and neutrons (neutral) in nucleus.
What is a Compound?
A combination of more than one element
What is an Atomic Number?
Number of protons in an atom
What is an Atomic Mass?
Number of protons plus neutrons in an atom
What is an Isotope?
Same element, but with different number of nuetrons
What is Radioactive Decay?
Radioactive isotopes release heat spontaneously from nucleus
How is an Element Radioactive?
An isotope with an unstable nuclei
What is an Element’s Half Life?
Time it takes for 1/2 the original atoms to decay
What are the 3 Types of Radioactive Emissions?
- Alfa Particles - Helium Nuclei, tend to be weak.
- Beta Particles - High speed electrons and antineutrinos, or positrons and neutrinos. (Can be stopped with sheet of aluminum foil).
- Gamma Radiation - High energy protons. (Can be stopped with block of led).
What is Carbon Dating?
Carbon in atmosphere is always found in same ratio - 12C is 99%, 13C is 1%, and 14C is 1 part per trillion. Half life of Carbon 14 is 5,730 years. Using this information, we can measure the amount of 14C in an object compared to the atmosphere to date it.
What is a Covalent Bond?
Elements sharing electrons
What is an Ionic Bond?
Opposite charged atoms form ions through bonds. (Cation - negatively charged, Anion - positively charged).
What is a Hydrogen Bond?
Very weak bonds between two hydrogen molecules
What is an Acid?
A substance that adds hydrogen to a solution by adding H+
What is a Base?
A substance that decreases the hydrogen ion concentration in a solution by adding OH-
What is pH?
Concentration of Hydrogen in a solution: ranges from 0-7 (acidic) to 7-14 (basic), with 7 being neutral. pH is the negative log of H+ concentration
What is Energy?
The ability to do work (power x time)
What is Power?
The rate at which work is done (energy/time)
What is Potential Energy?
Energy that has been stored, but not yet released
What is Kinetic Energy?
Energy of motion
What is Chemical Energy?
Energy in chemical bonds
What is Photosynthesis?
Conversion of light energy from the sun into chemical energy, common in plants.
(6H20 + 6C02 –> C6H12O6 + 6O2)
What is Chemosynthesis?
Process by which some organisms, such as certain bacteria, use chemical energy to produce carbohydrates
What is Cellular Respiration?
Chemical energy in glucose released through respiration, then used to grow, move, and metabolize. Used by all organisms, but is animals main source of energy.
What is Biomass?
A measure of the total mass of organisms within a particular region, standing crop is measure of total dry mass
What is Nitrogen?
Important for life (Amino Acids, Protein, and DNA). In 80 % of atmosphere as gas and can only be captured by bacteria. Animals can receive N by eating other organisms with N.
What is Eutrophication?
A process by which nutrients, particularly phosphorus and nitrogen, become highly concentrated in a body of water, leading to increased growth of organisms such as algae or cyanobacteria. Nitrogen - Saltwater, Phosphorous - Freshwater
What is Phosphorous?
A vital element in DNA, RNA, and ATP. Comes from sediments in biosphere through weathering and captured by plants. Animals obtain P by eating other organisms with P.
What is Ammonitication?
Break down of organic molecules to release Nitrogen. (Nitrification converts ammonia to Nitrogen)
What are the 4 Layers of Atmosphere?
(PUT ON NOTECARD)
- Troposphere (0 to 10 miles, mostly Nitrogen and Oxygen. Gets colder as you go up)
- Stratosphere (10-30 miles, gets hotter as you go up due to UV radiation, Ozone layer here)
- Mesosphere (31 - 65 miles, temp decreases as you go up)
- Thermosphere (65 - 370 miles, temp increases as you move up, and blocking most X rays)
What are Species?
A group of organisms different from another in size, shape, behavior, or biomechanics.
What is Species Richness?
The number of species in a given area
What is Species Evenness?
Relative proportion of different species in a given area
Microevolution vs. Macroevolution?
Microevolution - small scale (within a single population)
Macroevolution - scale that transcends the boundaries of a single species, creating a new one.
What is Genetic Diversity?
The range of genetic material present in a gene pool or population of a species.
What is Mutation?
A change in a gene or chromosome
What are the Key Features of Natural Selection?
- Individuals produce an excess of offspring
- Not all offspring survive
- Individuals differ in their traits
- Trait differences can be passed onto offspring
- Trait differences affect the ability to survive and reproduce
How Can Environmental Change Cause Extinction?
No favorable environment to move to, new environment may be already occupied, environmental change occurs too fast with no time to adapt
How Has Extinction Changed Since Arrival of Humans?
Half of vertebrate are extinct, habitat destruction, over harvesting, many invasive species, climate change, and emerging diseases.
What are Density Dependent Factors?
Influence survival and reproduction
ex: Limiting resource, carrying capacity
What are Density Independent Factors?
Unpredictable events
ex: Natural disasters
Types of Population Growth
Intrinsic Growth Rate - Natural growth
Logistic Growth - Limited by carrying capacity
Exponential Growth - Unlimited and rapidly increasing
What are K Selected Species?
Species that produce a few, often fairly large offspring but invest a great deal of time and energy to ensure that most of those offspring reach reproductive age. Seldom overshoot carrying capacity.
ex: Deer
What are R Selected Species?
Species that produce large numbers of usually small and short-lived offspring in a short period. Often overshoot carrying capacity.
ex: Fish
What is a True Predator?
An organism that consumes other organisms
What is a Keystone Species?
When loss can disproportionately have a large effect on ecosystem (usually in low #’s)
ex: kelp in trophic cascades (direct actions that control ecosystems)
What is Predator Mediated Competition?
When a predator increases competition of other species for resources
What is an Ecological Engineer?
Species that creates/maintains habitat for other species
ex: beaver dams
What is Demography? Immigration, Emmigration, Crude Birth Rate, Crude Death Rate?
The study of populations and how they grow
Immigration - moving into
Emigration - moving out of
Crude Birth Rate - # births per 1,000
Crude Death Rate - # deaths per 1,000
What is Doubling Time?
Years it takes for population to double (70/growth rate)
(US is 35 years)
What is Fertility Rate?
Average # of children each woman will have, education is #1 way to reduce. (US is 2.1 children)
What is Replacement Level Fertility?
The total fertility rate required to offset the average number of deaths
What are Age-Constructed Population Pyramids?
*Crude death rate can be balanced by large # of old people.
Population pyramids give age structure for countries
- If even, no growth, if inverted, more younger than old, if pyramidal, fast growth because more young than old
What is the Theory of Demographic Transition?
As country moves from subsistence economy (not money) to industrialization, undergoes predictable shift in population growth.
- Preindustrial - birth rate and death rate are high and equal
- Early industrial - birth rate is high, death rate very low
- Mature industrial - birth rate collapses and matches death rate
- Postindustrial - birth rate and death rate fluctuate but remain relatively even
What is the IPAT Equation?
Estimation of human lifestyle on earth
(Impact = Population x Affluence x Technology)
Total impact =
(population) x (consumption per person) x (impact per person)
What are Earth Layers?
- Core - innermost layer
- dense, mostly nickel and iron
- Mantle - molten rock
- magma circulates in convection cells
- Asthenosphere - outer mantle
- semi-molten rock
- Crust - outermost layer
- chemically distinct
- Lithosphere: made up of plates that sit on top of Asthenosphere
What Did Alfred Wagner Propose?
Proposed Pangea in 1912 from rock formations and similar fossils
What are the Types of Tectonic Plates?
Oceanic Plates - beneath ocean, high in iron and dense
Continental Plates - beneath land high in silicon dioxide and less dense
What are the 3 Types of Plate Contact?
- Divergent - plates move away from each other causing seafloor spreading and creation of mid ocean ridge
- Convergent - plates collide and create coastal mountains and deep sea trenches
- Transform - plates move sideways past each other producing earthquakes
Difference between Rocks vs. Minerals?
Minerals - solid chemical substances with uniform structures
Rocks - substance found in the lithosphere composed of one or more minerals
What is Weathering?
Rocks breaking up through erosion
What are the Functions of Soil?
- Medium for plant growth
- Recycling system
- Habitat for organisms
- System for water supply & purification
How is Soil Formed?
Comes from the physical and chemical weathering of rocks plus accumulation of organic material
What are the Soil Determining Factors?
- Parent material - base rock material
- Climate - don’t develop below freezing
- Topography - steep slopes more erosion
- Organisms - plants remove nutrients, animals mix soil
- Time - older soils have more organic matter
What are the Physical Properties of Soil?
Texture - determined by % of sand (large particles), silt (medium), and clay (small)
Porosity - How quickly water drains through soil, determined by texture (sand - fast, clay - slow)
What is the Difference Between Unconfined vs. Confined Aquifers?
Unconfined - found in porous rock covered with soil, recharges in days or weeks (more likely to be polluted because closer to surface)
Confined - surrounded by a layer of impermeable rock or clay, recharges in up to 20,000 years
How are Lake’s Classified by Productivity?
(based on level of primary productivity)
*low nutrients is low productivity
Oligotrophic - low productivity
Mesotrophic - moderate productivity
Eutrophic - high productivity
What are some Drought Consequences?
- Direct loss of human life, livestock, and crops
- Can alter nutrient cycling and soil fertility
- Poor land use can worsen during drought
What are Impermeable Surfaces?
Surfaces like pavement or buildings that prevent water penetration causing streams and river to possibly overflow
*In healthy systems, porous soils and wetlands can soak up excess rain water
What is a Levee?
Bank of soil on both sides of river sed to prevent flooding in floodplains (dike-ocean levee)
Problems:
- Reduces fertility of soils
- Nutrients carried downriver, settling in estuaries
- Can cause greater flooding downstream
- Encourages building in floodplains
What are Resovoirs?
Water help back by dam to control water for supply, electricity, flood creation and recreation
- can cause great floods
- fish must use ladder to get back up to optimal point
What are Aqueducts?
Ditches that carry water from one location to another
- can cause rivers to dry up
Aral Sea lost 60% of its size and formed two smaller lakes creating hotter summers and cooler winters
What is Desalination?
Removing salt from seawater
- Distillation: boiling water and capturing steam
- Reverse Osmosis: water forced through semipermeable membranes that saltwater cant pass through, creates brine that can causes environmental problems)
What is a Joule?
Basic unit of energy
- Total world consumption is 500EJ per year
2 Types of Mining?
Surface Mining - safe and cheap
Subsurface Mining - higher cost and health concerns
What is Crude Oil?
Oil can be refined by heating into:
Tar, asphalt, lubricating oils, heating oils, etc.
*Heat determines state of oil
Difference Between Modern Carbon vs. Fossil Carbon?
Modern carbon - comes from biomass/biofuels like corn or trees that have been created from the suns photosynthesis recently
Carbon Neutral
Fossil Carbon - carbon in fossil fuels created long ago
*Releases CO2
What is Energy Conservation and Ways it can be Reduced?
Conserving our energy is the #1 to reduce impact
Governments - Increase tax on energy use by implementing tiered rate system (low rate for low use, high rate for high use, credits for less energy)
Sustainable Design - Natural lighting, thermal inertia, green roof, recycled materials
What are Pathogens and its Types?
Disease causing organisms
- Viruses
- Bacteria
- Protozoans
- Parasitic worms/flukes (1/3 of world infected w/ worm)
What are Emergent Diseases?
*Not previously known/absent
ex: SARS (Severe acute respiratory syndrome)
- Virulent corona viruses jumping from animals to humans
