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Science - vocab

Science - grade 9 - vocabulary

variations differences in characteristics of organisms caused by genetic and environmental factors
biological diversity the number and variety of organisms in an area
species a group of organisms that share similar genetic and physical characteristics; these organisms can inter breed and produce fertile offspring
specation the evolution of different species from a single ancester
structural adaptation an inherited physical characteristic that helps an organism in it's environment
behavioral adaption an inherited characteristic behavior that helps an organism survive in it's environment
diversity index a measure of the biological diversity in an area, calculated by dividing the number of runs in a walk-through of an area by the total number of specimens
environment the area or conditions in which an organism lives; sometimes used to refer exclusively to natural areas on Earth
competition the struggle among individual organisms for access to a limited resource, such as food or territory
niche a habitat supplying the factors necessary for the existence of an organism or species; the conditions that are optimal for survival
broad niche an organism that has adapted to an extensive range of environmental conditions for survival; can live in various different conditions
narrow niche an organism that must have a very specific environmental conditions to survive and only plays a limited role in its habitat
generalist an organism with generalized requirements and adaptations that allow it to survive in variable conditions and depend on a variety of food sources
specialist an organism that is adapted to a very specific environment and having a narrow niche
specialization adaptations for surviving in very specific environment
symbiotic an interaction between organisms of different species living in close proximity to each other in a relationship that lasts over time
heritable a genetic characteristic; one that can be passed on from parent to offspring
reproductive strategy a method an organism uses to reproduce
asexual reproduction the formation of a new individual from a single organism
binary fision the splitting of a single celled organism into two new organisms approximately equal in size; ex: bacteria reproduce through this process
spores a single celled reproductive structure from which an individual offspring develops; plants, algae, fungi, and some protozoa produce spores
zoospores an asexual spore of some algae and fungi that moves by means of flagella
meristem an area of cell division of unspeciallized cells in the tips of roots and shoots that produce new growth in plants
clones an identical copy of a molecules, gene, cell, or entire organism
budding an asexual reproduction process in which a bud forms on an organism, grows, and eventually breaks away away to become a new organism independent of the parent
sexual reproduction reproductive process involving two sexes or mating types, resulting in offspring with genes from both parents
zygospore a single celled reproductive structure formed in sexual reproduction by some fungi
bacterial conjugation direct transfer of DNA from one bacterial cell to another bacterial cell through direct contact
zygote the new cell formed by the process of fertilization
pistil the seed producing, or female, part of a flower
stamen the pollen-bearing organ of a flower, consisting of the filament and the anther; the male fertilizing organ of a flower
ovule the female reproductive structure that develops into a seed-bearing plant
pollen tube in a plant, a tube that grows from a germinating pollen grain and enters the embryo sac in an ovule
embryo the part of a seed that develops into a plant
cotyledons is part of the embryo within the seed of a plant; the first leaves of the seedling; contains the stored food reserves from the seed
genetics the study of genes or inheritable traits
continuous variation is the combined effect of many genes and is often significantly affected by environmental influences
discrete variation inherited traits that have a limited number of variations, such as the ability or inability to role one's tongue
dominant trait an inherited trait that shows up in an offspring
recessive trait an inherited trait that shows up in the offspring only if both parents pass on the genes for this trait
mutation a change in the genetic information, or DNA, of an organism
mutagen an agent that can cause changes in the genetic information of an organism
DNA a molecule that stores genetic information for heritable traits and directs the structure and functions of cells
chromosomes in a cell, tightly packed strands of DNA visible under light microscope during cell division
gene a section of DNA on a chromosome that codes for a specific protein and function
somatic cells one of the cells that take part in the formation of the body; any cell other than a reproductive cell
genetic engineering the artificial introduction of genes from one organism into the genetic material of another organism
biotechnologies using or modifying living organisms to make marketable products; sometimes involves genetic engineering
aquaculture fish farming
domestic an animal that is no longer wild, but has been bred or tamed by humans to perform various functions
artificial selection technique in which individual plants or animals with desirable traits are bred together to develop plants or animals with specific traits
selective breeding technique in which individual plants or animals with desirable traits are bred together to develop plants or animals with specific traits
natural selection a natural occurring process in which only those organisms with the best traits for survival in an environment will survive to reproduce
extripation the extinction of a species from specific geographical areas
bio-indicator species species that help indicate environmental change
seed bank a collection of genetically diverse seeds
global treaties international agreements between many nations world wide
chemistry the study of the properties of matter and the changes it undergoes
caustic an agent that burns or destroys living tissue
homogeneous a mixture in which particles are uniformly scattered; has a uniform composition
heterogeneous a mixture in which the particles are not uniformly scattered
physical change change in form but not in chemical composition; no new substance is formed
chemical change change in which one or more new chemical substances are formed
Law of Definite Composition compounds are pure substances that contain two or more elements combined together in fixed proportion
electrolysis the process of decomposing a chemical compound by passing an electric current through it
element is a pure substance made up of one type of particle or atom
compound pure substances that are made up of two or more elements chemically compound together
atomic nucleus the center of the atom; contains protons and neutrons
proton the positively charged particles making up the nucleus
neutrons uncharged particles in the nucleus with a mass slightly greater than protons
element symbol symbols for all the known elements
chemical family used to describe a group of related elements that have similar properties
atomic mass is the average mass of an atom of an element
atomic number is the number of protons an element has in it's nucleus
periods the horizontal rows of the periodic table
ionic compound formed when atoms transfer electrons to or from other atoms
molecular compound formed when atoms share electrons
chemical formula uses symbols and numerals to represent the composition of a pure substance
molecule is the smallest independent unit of a pure substance and is generally a cluster of atoms joined together
diatomic molecule are molecules made of 2 atoms of the same element
binary compound a compound made from 2 elements
ion is a particle or group of particles with a positive or negative charge
conductivety is the ability of a substance to carry an electrical current
chemical reaction 2 or more substances that under-go a reorganization of atoms to form other substances
reactants the substances that go into a chemical reaction
products substances produced by a chemical reaction
exothermic chemical reactions that gives off energy
endothermic chemical reactions that absorb energy
reaction rate is a measure of how fast a reaction occurs
catalyst is a substance that speeds up the rate of a reaction without being changed itself
enzyme is a natural catalyst made by living things
inhibiter a substance that slows down chemical reactions
corrosion is the oxidation of metals or rocks in the presence of air and moisture
rust iron oxide, a product of the chemical reaction of iron, oxygen, and moisture
galvinization the process of coating metals in a thin layer of zinc
combustion is the highly exothermic combination of a substance with oxygen
nutrients a chemical in food, used for energy, growth, body building, or cell repair
carbohydrates an organic nutrient made of carbon, hydrogen, and oxygen
proteins an organic nutrient composed of a chain of amino acids
lipids an organic nutrient that does not dissolve in water
vitamins a molecule that helps enzymes function in the body
macronimerals a mineral that the body requires in the amount of 100mg/day or more in order to maintain health
trace element a mineral that the body requires in the amount of less than 100mg/day in order to maintain health
enzymes a special protein molecule that regulates chemical reactions in living organisms
pesticide a chemical used to control pests
herbicide a chemical used to control weeds
insecticides a chemical used to control insects
fungicides a chemical used to control mold and fungi
biological magnification the process where by chemicals accumulates in the tissues of organisms along the food chain
acidic having a ph below 7
basic having a ph higher then 7
acids a chemical that producers an acidic substances, having a ph value of less than 7
bases a chemical that produces a basic substances, having a ph value of more than 7
indicator a chemical that changes color to indicate whether a substance is an acid or base
litmus a mixture of plant compounds used as an indicator
ph scale a scale that measures the ph of a substance
ph paper paper saturated in a chemical to show whether a substance is an acid or base
acid percipitation rain or snow containing acid compounds
liming adding calcium carbonate to the environment
acid base neutralization the combining of an acid and base to produce salt water
catalytic a device that encourages complete oxidation during combustion
catalyst a substance that speeds up chemical reactions without being used up
oxidation a chemical reaction in which oxygen combines with other elements to make new ones
scrubbers a device using water or a solution for purifying gases or vapors
sorbent a substance that has the property of collecting molecules of another substance by absorption
pollutant any material, or form of energy, that will cause harm to living organisms
pollution an alteration of the environment producing a condition harmful to living things
toxicity the ability of a chemical to cause harm to an organism
chronic toxicity the ability of a chemical to cause harm to an organism only after multiple exposures
LD50 represents the individual dose required to kill 50% of a population of test animals
non-persistant wastes that can been broken down into non-polluting compounds
persistant wastes that accumulate in the environment
biological indicators a living organism whose state indicates the health of an environment
macroinvertabrate an organism visible to the naked eye with no backbone
point source a specific location where pollution originates from
non-point source a source of pollution with no originating point
N.I.M.B.Y. Not in My Back Yard
ground water water that filters down through the soil and fills space in the ground
aquifier an underground reserve of water
biodegradable able to be broken down by the environment
solvent a substance that can be used to dissolve other substance
sanitary landfill a landfill with waterproof lining and covered in dirt
leachate a liquid that results when wastes decompose
secure landfill a landfill that disposes of toxic or hazardous materials safely
bioremediation using living organisms to break down toxic substances into non-toxic substances
static electricity a charge produced by rubbing or touching objects together
unbalanced charges a more correct term for static electricity, because the charges are not stationary
Law of Charges - unlike charges attract - like charges repel - charged objects attract uncharged objects
insulators material that does not allow charges to move freely on or through them; most non-metals are insulators; ie: rubber
conductors material that allow charges to move freely; most metals are conductors
superconductors material that offers little or no resistance to the flow of charges
discharge electrons either enter an object to make up for a shortage, or an excess of electrons leave the object
neutralized become balanced
grounding connecting an object to Earth with conducting wire to safely re-balance a charge
circuit provides a continuous pathway for charges to move
battery is a combination of cells
switch is used to open or close a circuit to control the current running through it
resistor is a symbol used to represent one of many different loads
loads items along a circuit that convert electricity into other forms of energy
amperers an instrument used to measure large currents
galvonometer an instrument used to measure very weak electric current
ammeter an instrument used to measure large currents
potential difference the difference in energy per unit of charge between one point in the circuit and another point in the circuit
voltage the amount of potential energy between two points on a circuit; the difference in charge between the two points is called the voltage
volt the standard unit for potential difference
voltmeter an instrument to measure voltage
resistance is a property of a substance that hinders motion of electric charge and converts electric energy into other forms of energy
Ohm the standard unit for electrical resistance
Ohmeter an instrument that measures electrical resistance
Ohm's Law R=V/I resistance = voltage / current voltage - is the potential difference between 2 points current - current flowing through the resistance
parallel circuits circuits with several current paths
series of circuits circuits with only one current path
branch each current path in a parallel current; a parallel circuit has a series of branches connected side by side
thermocouple a loop of two wires made of different types of metals that converts heat to energy
thermo-electric generator is a device based on a thermocouple that converts heat directly into electricity without moving parts
electro-chemical cell is a device capable of generating electrical energy from chemical reactions
electrode the 2 metal in a voltaic or electo-chemical cell
electrolyte a substance that can conduct electricity
primary cell a cell that cannot be recharged
secondary cell a rechargeable cell that uses chemical reactions which can be reversed
electric generator a device that converts mechanical energy into electric energy
electromagnet a strong temporary magnet created by inserting a soft iron core into a coil of wire and then passing a current through the wire
alternating current electricity produced in a generator where the current flowing from the generator changes direction regularly
dynamo a generator that produces direct current
commutator a part of the dynamo generator that serves to reverse the induced current as it changes direction making the current flow in only one direction
rotor the rotating core of an AC motor
stator is a 2 pole electromagnet that surrounds the rotor
transformers used to step-up the voltage for efficient transmission of current over long distances
circuit breaker acts like a switch and safety device that can cut all power coming into the home
fuse contains a metallic conductor that melts when excessive current heats it up; this opens the circuit until the fuse is replaced
branch circuit supplies power to one or more wall plugs or lights connected in parallel by cables in the house walls
neutral wire the white insulated live wire in each branch circuit
hot wire black insulated live wire in each branch circuit
ground wire is either bare copper or covered with green insulation; is the third wire in the branch circuit
electrical code a set of standards for all electrical wiring
digital machines machines that process numerically coded information
binary code a sequence of on and off signals
transistors the electronic switches in a modern digital device; solid state components that can be turned on and off by electric signals
renewable can be continually replenished
therno-electric plants plants that burn fossil fuels to produce electricity
non-renewable recources fuels consumed faster than they can be produced by nature
open pit mining mining in which the fuel, such as coal, is uncovered and dug directly from the ground
greenhouse gases gases that help regulate the temperature on earth by holding in the heat from the sun in our atmosphere
hydro-electric plants plants that use water pressure to generate electric energy
nuclear fission the process whereby uranium is split into smaller atoms, making energy
thermonuclear using the energy released in nuclear fission to generate electricity
nuclear fusion the process whereby 2 smaller atoms join into a large atom, producing tremendous energy; how the sun generates energy
thermal pollution releasing unwanted heat straight into lakes or streams
co-generation systems electricity generating stations that produce electricity and also supply thermal energy
geothermal energy thermal energy contained in the inner portions of earth
frame of reference is a set of axes of any kind that is used to describe the positions or motions of things
celestial bodies all objects seen in the sky; sun, stars, moon, planets
constellations groupings of stars that form patterns, which appear like objects and are given names; ie: Orion the Hunter
planets celestial bodies in our solar system that orbit the sun
azimuth is the angle measured clockwise from north when measuring altitude-azimuth coordinates
altitude is the angle measured above the horizon in degrees when measuring altitude-azimuth coordinates
altitude-azimuth coordinates locate a celestial body relative to a fixed Earth (as though the celestial bodies are circling Earth)
astrolabe is a devise used to measure the altitude of an object
compass a device used to measure an object's azimuth
Earth centered model a model of the universe that places earth at the center with the sun, moon, and planets revolving around it
Sun centered model a model of the universe that places the sun at the center with the Earth, planets and moons revolving around it
telescope a device used to magnify objects at great distances
objective lens the large lens at the front of a telescope
ocular lens the lens through which you view a magnified objects using a telescope
resolving power determines the fineness of detail a telescope can produce of an object in view
refracting telescope a telescope that has a lens for the objective
reflecting telescope a telescope that has a mirror for its objective
elipse a figure that looks like a squashed circle; planets in the solar system move in elliptical orbits around the sun
universal gravitation Newton's Law states that all objects attract all other objects and provides an explanation for the planets elliptical orbits
spectrum sunlight, which is white light, is made up of all colors
spectroscope a device that produces a focused spectrum
spectral lines dark lines or bright lines observed in the spectra of stars
spectrascopy the study of spectra spectrum produced when a beam of light is passed through a prism
diffraction grating a device made of thousands of closely spaced slots through which light is passed in order to produce a spectrum
spectral analysis the study of spectra
Doppler Effect the phenomenon that the observed frequency of a wave changes if the source of the wave and the observer are moving toward or away from one another
red shift when spectral lines move toward the longer wave length part (red end) of the spectrum
adaptive optics is the technology that adjusts the mirror of a telescope or adjusts the image of the telescope, to control the effects of the constant changes in earth's atmosphere
triangulation is a method of measuring distance indirectly by creating an imaginary triangle between an observer and an object who's distance is to be estimated
astronomical unit (AU) is the distance from earth to the sun; 150 million km
light year the distance that light travels in one year; approximately 63,240 AU or about 9.5 trillion km
Created by: SNT