Introduction (Ch. 1&2) Flashcards
Environmental science?
The field that looks at interactions among humans and nature.
Environment?
A sum of all the conditions surrounding us that influence life
System?
A set of interacting components that influence one another by exchanging energy or materials
Ecosystem?
The living and nonliving components of a particular place on earth
Biotic?
The living part of the earth (animals, plants)
Abiotic?
The non living part of the earth (soil, air, water)
Environmental studies?
Includes environmental science, the study of interactions among human systems and those found in nature along with other subjects such as environmental policy, economics, literature, and ethics
Humans later natural systems by?
Manipulating their environment more than any other species
Ecosystem services?
Environments provide life supporting services such as clean water, timber, fisheries, crops
Environmental indicators?
Describe the current state of the environment
Sustainability?
Living on earth in a way that allows us to use it’s resources without depriving future generations of those resources
Environmental indicators? Examples?
They help us describe the current state of an environmental system. The 5 global environmental indicators are biological diversity, food production, average global surface temperature and carbon dioxide concentrations in the atmosphere, human population, resource depletion
Biological diversity?
The diversity of life formed in an environment. It includes genetic, species, and ecosystem diversity.
Genetic diversity?
A measure of the genetic variation among individuals in a population. Populations with high genetic diversity are better able to respond to environmental change than populations with lower generic diversity.
Species diversity?
The number of species in a region or in a particular type of habitat
Species?
A group of organisms that is distinct from other groups in form, behavior or biochemical properties. Individuals in a species can breed and produce fertile offspring.
Ecosystem diversity?
A measure of the diversity of ecosystems or habitats that exist in a particular region.
Food production?
Our ability to grow good to nourish the human population. We use science and technology to increase the amount of food we can produce on a given area of land.
Greenhouse gases?
Gases in our planets atmosphere that act like a blanket, trapping heat near Earth’s surface.
The most important is carbon dioxide
Anthropogenic?
Caused by human activities
Human population?
7 billion since Octoberr
Over a million additional people are added to earth every 5 days
Resource depletion?
- as the human population grows, the resources necessary for our survival become increasingly depleted
- some natural resources such as coal, oil, and uranium are finite and cannot be renewed or reused
- other natural resources like aluminum or copper, also exist in finite amounts but can be recycled
Development?
Improvement in human well-being through economic advancement. As economies develop, resource consumption also increases.
Sustainable development?
Development that balances current human well-being and economic Advancement with resource management for the benefit of future generations
In order to live sustainably:
- environmental systems must not be damaged beyond their ability to recover
- renewable resources must not be depleted faster than they can regenerate
- non renewable resources must be used sparingly
Defining human needs:
- people in developed nations might say that they “need” electricity
- people in the developing world have never heard of this modern convenience
- basic human needs: air, water, food, and shelter
Ecological footprint?
A measure of how much a person consumes, expressed in area of land
Scientific method:
- observations & questions
- hypothesis
- collecting data
- interpreting results
- disseminating findings
Hypothesis?
An educated guess that can be proved or disproved through controlled experimentation
-a null hypothesis is a statement that can be proved wrong
Collecting data (replication)
Repeating the measurement many times
Collecting data (sample size)
The number of times the measurement is repeated
Collecting data (accuracy)
How close a measured value is to the actual or true value
Collecting data (precision)
How close to one another the repeated measurements are
Collecting data (uncertainty)
How much the measure differs from the true value
Interpreting results:
- once results have been obtained, analysis of the data begins. This process involves two types of reasoning, inductive and deductive.
- IR is the process of making general statements from specific facts or examples
- DR is the process if applying a general statement to specific facts or situations
Disseminating findings?
Scientists present papers at conferences and publish the results of their investigations. This allows other scientists to repeat the original experiment and verify or challenge the results.
Theory?
A hypothesis that has been repeatedly tested and confirmed be multiple groups of researchers and is widely accepted.
Natural law?
When a theory has been tested multiple times and there are no known exceptions. Ex. Law of gravity and laws of thermodynamics
Controlled experiment?
An experiment conducted in the controlled conditions of a laboratory
Natural experiments?
When a natural event, such as a volcano, acts as an experimental treatment in an ecosystem
Experimental science presents unique challenges:
- there is no “control” planet to compare the Earth with
- it is difficult to decide what is better or worse for the environment that something else
- environmental science has so many interacting parts, it is not easy to apply one system to another
- human well-being is a concern b/c people that are unable to meet their basic needs are less likely to be interested in saving the environment
How can you find percentage of growth?
(B + I) - (D + E) /Total X 100
Matter
Anything that occupies space and that has mass
Mass
A measure of the amount of matter an object contains
Weight
The force that results from the action of gravity on mass
Atom
The smallest particle that can contain the chemical properties of an element
Element
A substance composed of atoms that cannot be broken down into smaller, simpler components. Elements can be solid, liquid, or gas
Periodic table
Lists all the elements currently known
Molecules
Particles containing more than one atom
Compounds
Molecules that contain more than one element
Atomic number
The number of protons in the nucleus of a particular element
Mass number
The total number of protons and neutrons in an element
Isotopes
Atoms of the same element that have different numbers of neutrons, and therefore different atomic masses
Radioactive decay
The spontaneous release if material from the nucleus of an unstable isotope
- radioactive decay changes the radioactive element into a different element. Uranium 235 decays to form thorium 231
- uranium is card the parents and thorium the daughter
Half - life
The time it takes for one- half of the original radioactive parent atoms to decay
- some elements that undergo radioactive decay emit harmful radiation
- knowledge of the half- life allies scientists to determine the length of time that a radioactive element may be dangerous
Covalent bonds
Elements that form compounds by sharing electrons
Ionic bonds
Elements that form compounds by transferring electrons from one element to another
-when this happens, one atom becomes electron deficient (positively charged) cation and one atom becomes electron rich (negatively charged) anion
Hydrogen bonds
A weak chemical bond that forms when hydrogen atoms that are covalently bonded to one atom are attracted to another atom on another molecule
-water is known as a polar molecule, one side is more positive and other side is more negative
Surface tension
The result from the cohesion of water molecules at the surface of a body of water
Capillary action
When adhesion of water molecules to a surface is stronger than cohesion between the molecules
Boiling and freezing
At earths surface, waters boils at 100 degrees Celsius and freezes at 0 degrees Celsius
Water as a solvent
Many substances dissolve well in water b/c their polar molecules bond easily with other polar molecules
Acid (H+)
A substance that contributes hydrogen ions to a solution
Base (OH-)
A substance that contributes hydroxide ions to a solution
pH
A way to indicate the strength of acids and bases -the pH scales range from 0-14 7 is neutral Above 7 is basic Below 7 is acidic
Chemical reaction
Occurs when atoms separate from the molecules they are a part of or recombine with other molecules
Law if conservation of matter
Matter cannot be created or destroyed, it can only change form
Inorganic compounds
Compounds that do not contain carbon or do contain carbon, but only carbon bound to elements other than hydrogen
Examples: NH3, NaCl, H2O, CO2
Organic compounds
Compounds that have carbon-carbon and carbon- hydrogen bonds
Carbohydrates
Compounds composed of carbon, hydrogen, and oxygen atoms
Example: C6H12O6 glucose
Proteins
Made up of long chains of nitrogen- containing organic molecules called amino acids (for cellular functions)
Nucleic acids
Organic compounds found in all living cells
DNA and RNA (macromolecules)
Lipids
Smaller biological molecules that do not mix with water.
Example: fats, waxes, and steroids
Cells
The smallest structural and functional opponent of organisms
- single cells: bacteria and some algae
- multicellular: bring shrimp
Energy
The ability to do work
Energy = power X time
Power
The rate at which work is done
Kinetic energy
Energy of motion
Potential energy
Energy that is stored
Chemical energy
Potential stores in chemical bonds
Temperature
The measure of the average kinetic energy of a substance
First law of thermodynamics
- energy is neither created or destroyed
- you can’t get something from nothing
Second law of thermodynamics
When energy is transformed, the quantity of energy remains the same, but it’s ability to do work diminishes
Energy efficiency
The ratio of the amount of work that is done to the total amount of energy that is introduced into the system
Energy quality
The ease with which an energy source can be used for work
Entropsy
All systems move toward randomness rather than toward order
-this randomness is always increasing in a system, unless new energy from the outside of the system is added to create order
Open system (in terms of energy)
Exchanges of matter or energy occur across system boundaries
Closed system (in terms of matter)
Matter and energy exchanges across system boundaries do not occur
Steady state
In a system, when input equals output
Negative feedback loops
When a system responds to change by returning to it’s original state, or at least by decreasing the rate at which the change is occurring
Positive feedback loops
When a system responds to change by increasing the rate at which the change is occurring
