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90 Cards in this Set

  • Front
  • Back
What are the symbols for hydrogen and hydroxol?
H+ and OH-
Ph of 7 =
the same # of hydrogen ions and hydroxlions
Nucleic acids
DNA
not a polymer and does not dissolve in water
lipid
life has never seen it and is a very toxic chemical
xenobiotic
how many amino acids are there?
20
How many amino acids do humans make?
12
How do we get the other amino acids
the other 8 are obtained by eating plants or animals
how many amino acids do plants have?
20
Who first published info on nucleic acids?
Watson and Krick
Nucleotides always line up with each other unless there's a ______
mutation
T or F: mutations are mostly leathal, but some can be beneficial.
true
_____ is central to environmental science:
Chemistry
An ____ is a fundamental type of chemical substance.
element
• Elements are composed of _____
atoms
• Each atom has a certain
number of:
• protons (+ charge)
• electrons (– charge)
• neutrons (no charge)
___ elements occur in nature, each with its characteristic
number of protons, neutrons, and electrons.
92
electrically charged atoms or combinations of
atoms
Ions
combinations of two or more atoms
Molecules
molecules consisting of multiple elements
Compounds
uncharged atoms sharing
electrons (CO2)
covalent bond
charged atoms held together by
electrical attraction (NaCl)
ionic bond
Water is a unique compound because:
• Hydrogen bonds
give water properties
that make it a vital
molecule for life:
• Is cohesive
• Resists temperature
change
• Ice insulates
• Dissolves many
chemicals
Salt (NaCl) in seawater is broken up into ___ ____ ____ ions.
sodium (Na+)
and chloride (Cl–)
• Stable hydrogen bonds in ice make it less dense than
water, with its unstable hydrogen bonds.
Why ice floats on water
• Water dissolves many chemicals.
Water, the “universal solvent”
• If H+ concentration is greater than OH– concentration,
• then solution is acidic.
• If OH– is greater than H +,
• then solution is basic.
Organic compounds
• Consist of carbon atoms and,
generally, hydrogen atoms
• Joined by covalent bonds
• May include other elements
• Highly diverse; C can form
many elaborate molecules
• Vitally important to life
Macromolecules
• Large molecules essential for life:
• Proteins
• Nucleic acids
• Carbohydrates
• Lipids
long chains of
repeated molecules
polymers
Consist of chains of amino acids; fold into complex
shapes
Proteins
Give structure, energy, immune system, hormones,
enzymes
Proteins
consist of chains of sugars.
• Complex Carbohydrates
• For energy, also structural (cellulose, chitin)
Carbohydrates
• Do not dissolve in water
Lipids
4 examples of lipids
• Fats and oils
• Phospholipids
• Waxes
• Steroids
double-stranded chain (double helix)
DNA =
• Encode genetic information and pass it on from
generation to generation
DNA and RNA
single-stranded chain
RNA
functional stretches of
DNA, code for the synthesis of
proteins.
Genes
• Paired strands of
nucleotides make
up ___ ____ ____
DNA’s
double helix.
• Basic unit of organismal organization; compartmentalize
macromolecules and organelles
Cells
energy of position
Potential energy
energy of movement
Kinetic energy
Can change position, physical composition, or
temperature of matter
Energy
Laws of thermodynamics
• __ ___: Energy can change form, but cannot be
created or lost.
First Law
Laws of thermodynamics
• ____ ____: Energy will tend to progress from a
more-ordered state to a less-ordered state (increase in
entropy).
Second Law
____ ____ is only part of the sun’s electromagnetic
radiation.
Visible light
primary producers (e.g., plants), to
manufacture food.
autotrophic
organisms,
turns light energy from the sun into
chemical energy that organisms can use.
Photosynthesis
Organisms use stored energy via ______, which
splits sugar molecules to release chemical energy.
respiration
animals, fungi, most microbes
heterotrophs
comes from deep
underground; radiation
in Earth’s core heats the
inside of the planet and
rises to the surface
(driving plate tectonics,
volcanoes, etc.).
Geothermal energy
creates tidal
energy.
• Gravitational pull of the
moon
Some organisms and communities live without sunlight
and are powered by _____.
chemosynthesis.
imprint in
rock of a dead
organism
Fossil
Thefossil record shows that:
• Species today are a tiny fraction of all that ever lived.
• Earlier organisms evolved into later ones.
• The number of species has increased through time.
• Episodes of mass extinction have occurred.
• Eukaryotes are only ~ 600 million years old.
(living things)
Biotic factors
(nonliving things)
Abiotic factors
the study of how the natural
world works, how our environment affects us, and how
we affect our environment.
Environmental science
like sunlight cannot be depleted.
Renewable resources
like oil CAN be depleted.
Nonrenewable resources
Who said:
• Population growth will
lead to starvation, war,
disease.
• Death rates check
population unless birth
rates are lowered.
Thomas Malthus (1766-1834)
the area of land and water
needed to produce the resources a person or population
uses, plus the amount needed to dispose of their waste.
The “ecological footprint”
Developing solutions to
environmental problems.
Applied goal
drawing on
many diverse
disciplines.
interdisciplinary
field
Name two applications of science.
Policy decisions and
management practices
govern how the universe works.
Fixed natural laws
All events arise from causes, and cause other events.
causes/ cause
• Results may ___ or ____ ___ ___ a hypothesis.
reject/fail to reject
• Results ____ ____ a hypothesis, but only lend support
to it by failing to reject it.
never confirm
Experiments:
_____ or ____ ones are often necessary.
Natural/correlational
Manipulative experiments
are _____.
strongest
Also can be referred to as the
manipulated variable, which is altered in some
predetermined way by the investigator.
Independent variable:
Also can be referred to as the
responding variable, whose response is measured or
observed when the independent variable is
manipulsted.
• Dependent variable:
an additional experiment, set up
exactly like the other experiments, except that the
independent variable(s) are not manipulated.
A control group
an educated guess, to be tested
Hypothesis
a dominant view; may shift if new results
show old results or assumptions to be wrong
Paradigm
a well-tested and widely accepted explanation,
validated by much previous research
Theory
generalizations about what has happened,
from which we can generalize about what we expect
to happen.
Laws
explanations of observations (or of
laws).
Theories
consists of an outer membrane, of lipids and an inner fluid-filled chamber containing organelles
eukaryotic cells
organelles
internal structures that perform specific functions
lacking membrane bound organelles and an enclosed nucleus
prokaryotic cell
How old could a prokaryotic cell be?
4 billion years old
How much C02 do humans release?
4 times as much as we inhale
selsction that drives a feature in one direction rather than another
directional selection
produces immediate traits,in esscence preserving the status quo.
Stablilizing selection
Traits diverge from their starting condition in two or more directions
disruptive selection