Chapter 2 Flashcards
Environmental Systems: Matter, Energy, and Ecosystems
1
Q
Watershed
A
area of land that drains into a body of water
2
Q
Hypoxia
A
decomposition of phytoplankton depletes water
3
Q
System
A
network of relationships that influence each other by exchanging energy, matter, information
4
Q
Lithosphere
A
rock and sediment crust of the Earth
5
Q
Atmosphere
A
air surrounding Earth
6
Q
Hydrosphere
A
water
7
Q
Biosphere
A
living organisms on Earth and nonliving components
8
Q
Feedback loop
A
output is input back into the same system
9
Q
Negative feedback loop
A
system in one direction causes movement in the opposite direction
10
Q
Dynamic equilibrium
A
negative feedback systems that move in opposite directions at equivalent rates
11
Q
Homeostasis
A
tendency of a system to maintain stable internal conditions
12
Q
Positive feedback loop
A
output leads to increased input, stimulating another output (e.g. heat warms glaciers, causing melting, exposing more surface area to heat)
13
Q
Runoff
A
precipitation that flows over land
14
Q
Airshed
A
geographic area that produces pollutants that may land in a waterway
15
Q
Matter
A
material with mass that occupies space
16
Q
Chemistry
A
interactions of matter
17
Q
Law of conservation of matter
A
matter can be transformed, not created/destroyed
18
Q
Elements
A
substances with specific properties that cannot change, organized into the periodic table (e.g. uranium powers nuclear reactors)
19
Q
Atoms
A
smallest unit with all an element’s chemical properties
20
Q
Protons
A
positively charged, determine atomic number
21
Q
Neutrons
A
no charge
22
Q
Electrons
A
negative charge
23
Q
Nucleus
A
dense center of an atom (protons and neutrons)
24
Q
Isotope
A
element varies with neutrons
25
Radioactive
isotopes that change identity by emitting subatomic particles/radiation
26
Half-life
time an isotope takes to half-decay (700 million years for uranium-235)
27
Charged ion
atom gains/loses an electron (charge indicates how electrons are affected, e.g. Ca2+ lost two electrons, H+ lost one)
28
Molecules
combinations of two or more chemically bonded atoms
29
Compound
molecule made of multiple elements (e.g. Water, H2O and carbon dioxide, CO2)
30
Ionic bonds
ions of different charges attract/bind
31
Covalent bonds
electrons are shared between atoms without electric charges
32
Mixtures
atoms and molecules come together without reacting
33
Solution
even mixture
34
Neutral
equal concentrations of ions
35
Acidic
solution with higher concentration of hydrogen
36
Basic/alkaline
solution with higher concentration of hydroxide
37
pH scale
quantifies acidity/alkalinity of a solution, logarithmic
Water has a pH of 7 (H+ concentration of 10-7)
Acid has a pH below 7
Bases have a pH above 7
38
Organic compounds
compounds made of carbon atoms joined covalently
39
Hydrocarbons
organic compounds containing only hydrogen and carbon, like fossil fuels and petroleum products
40
Polymers
long chains of repeated molecules in organic compounds
41
Macromolecules
large molecules like polymers and lipids
42
Proteins
polymers made of amino acids, found in skin, hair, muscles, as enzymes that catalyze chemical reactions
43
Nucleic acids
deoxyribonucleic acid and ribonucleic acid, carry hereditary information, including blueprint for producing proteins; polymers made of nucleotides (molecules)
44
Genes
regions of DNA that encode for specific proteins
45
Carbohydrates
simple/complex sugars, such as glucose (blood sugar), cellulose (complex, found in leaves/bark/stems/roots), chitin (in insect exoskeletons)
46
Lipids
diverse group of molecules that don’t dissolve in water (fats, oils (store energy), waxes (structural), steroids (hormones))
47
Energy
ability to change position/composition/temperature of matter
48
Potential energy
energy of position
49
Kinetic energy
energy of motion
50
Chemical energy
potential energy stored in bonds of atoms
51
First Law of Thermodynamics
energy can change forms, but not be created or destroyed
52
Second Law of Thermodynamics
entropy
53
Autotrophs
organisms that use photosynthesis to transform molecules with low-energy bonds to sugar molecules with high-energy bonds using the Sun’s radiation
54
Photosynthesis
6CO2 + 6H2O + solar energy → C6H12O6 + 6O2
55
Chemosynthesis
deep-sea bacteria use chemical-bond energy from hydrogen sulfide (H2S) to turn inorganic carbon to organic carbon compounds
56
Cellular respiration
6CO2 + 6H2O + 3H2S → C6H12O6 + 3H2SO4
57
Heterotrophs
organisms that gain energy by feeding on other organisms
58
Ecosystem
all organisms/nonliving entities that interact in an area at one time (energy and matter cycle)
59
Estuary
ecosystem where rivers flow to the ocean, mixing salt and freshwater
60
Primary production
conversion of solar energy into chemical bonds in sugars
61
Gross primary production
total chemical energy from autotrophs
62
Net primary production
energy remaining after respiration is used to generate biomass
63
Secondary production
energy is used by consumers to generate biomass
64
Productivity
rate at which energy converts to biomass
65
Net primary productivity
energy/biomass remaining in an ecosystem after autotroph metabolizes enough for their own maintenance through cellular respiration
66
Ecotones
areas where adjacent ecosystems share resources/interact
67
Landscape ecology
scientists view systems of multiple ecosystems
68
Patches
areas of a habitat of an organism (spatial array)
69
Mosaic
patches are spread out over a landscape
70
Conservation biology
study of loss, protection, restoration of biodiversity
71
Geographic information systems
satellite imaging and computer software that layer sets of data on geology, hydrology, vegetation, animal species, human development, etc.
72
Model
simplified representation of complex natural processes
73
Ecological modeling
constructing/testing models to explain/predict ecological systems
74
Nutrient cycles/biogeochemical cycles
elements/molecules travel through the spheres in dynamic equilibrium
75
Reservoir
pool, like a person, cow, rocks, and the atmosphere
76
Residence time
time a nutrient spends in a reservoir
77
Source
reservoir releases more materials than it takes
78
Sink
reservoir accepts more materials than it releases
79
Flux
rate at which materials move between reservoirs
80
Hydrologic cycle
summarizes how water flows through the environment
81
Evaporation
convert water from liquid to gas, using heat, wind, exposure
82
Transpiration
release of water vapor by plants, leaving substances dissolved in water behind
83
Precipitation
rain/snow, which may be taken into plants, animals, or most commonly runoff
84
Groundwater
some precipitation sinks through soil/rock
85
Aquifers
regions of rock and soil that make underground reservoirs of water
86
Water table
upper limit of groundwater in an aquifer
87
Carbon cycle
describes carbon routes through the environment
88
Nitrogen cycle
nitrogen becomes biologically active and enters the biosphere/lithosphere
89
Nitrogen fixation
combine nitrogen with hydrogen to form ammonia (NH3), whose water-soluble ions of NH4+ (ammonium) can be taken by plants
90
Nitrogen-fixing bacteria
bacteria that convert nitrogen gas to ammonia
91
Nitrification
ammonium ions to nitrate ions NO2-, then NO3-, which plants take up
92
Denitrifying bacteria
convert nitrates back to nitrogen gas, releasing it back to the atmosphere
93
Bottleneck
step that limits flux of nitrogen out of the atmosphere (nitrogen fixation)
94
Phosphorus cycle
processes that move phosphorus from sinks to living matter
