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