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Science Focus 9

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Science Focus 9 Glossary How to Use This Glossary This Glossary provides the definitions of the key terms that are shown in boldface type in the text (instruc- tional boldfaced words such as “observe” and “gather” used throughout the investigations are not included). Other terms that are not critical to your understanding, but that you may wish to know, are also included in the glossary. The Glossary entries also show the page number where you can find the boldfaced words. a ϭ mask, back uh ϭ taken, focus oh ϭ home, loan ee ϭ leaf, clean ah ϭ car, farther e ϭ met, less u ϭ wonder, Sun i ϭ simple, this oo ϭ food, boot ae ϭ same, day uhr ϭ insert, turn ih ϭ idea, life aw ϭ dawn, hot alternating current (AC) electricity atomic mass the average mass of an A produced in a generator where the atom of an element absorption in biology, the process by current flowing from the generator atomic nucleus the centre of the atom; which dissolved food particles pass changes direction regularly contains the protons and neutrons from the small intestine to altitude is the angle measured above atomic number the number of the capillaries the horizon in degrees when measur- protons in the nucleus of an atom ing altitude-azimuth co-ordinates acid a chemical that produces an azimuth is the angle measured clock- acidic substance, having a pH value altitude-azimuth (alt-azimuth) wise from north when measuring of less than 7 co-ordinates locate a celestial body altitude-azimuth co-ordinates acid precipitation rain or snow con- relative to a fixed Earth (as though the celestial bodies are circling Earth) taining acid compounds from the air B acid rain rain that contains higher ammeter an instrument used to mea- than normal levels of acid; caused by sure larger currents bacterial conjugation the direct waste gases released into the atmos- amperes the unit used to measure transfer of genetic material (DNA) phere by industries and automobiles; electric current (A). Milliamperes from one bacterial cell to another damaging to the environment (mA) is also commonly used ballistic missile a rocket with a acid-base neutralization the aquaculture fish farming bomb as a payload, launched in a trajectory that sends it up into space combining of an acid and a base aquifer an underwater reserve of water to produce salt and water and down onto its target artificial satellite a satellite made acidic having a pH value of less than 7 bar graph a diagram consisting by humans, such as a spacecraft or of horizontal or vertical bars that acute toxicity the ability of a chemical telescope represent (often numerical) data to cause harm to an organism with artificial selection technique in only one exposure base a chemical that produces a basic which individual plants or animals substance, having a pH value of more adaptive optics is the technology with desirable traits are bred than 7 that adjusts the mirror of a telescope, together to develop plants or or adjusts the image of a telescope, to animals with specific traits; also basic having a pH value of more than 7 cancel the effects of the constant called selective breeding battery a combination of cells, either changes in Earth’s atmosphere asexual reproduction the formation wet or dry algae type of aquatic micro-organ- of a new individual from a single behavioural adaptation an inherited ism, capable of photosynthesis organism characteristic behaviour that helps an algal bloom large increase in astrolabe is a device used to measure organism survive in its environment population of algae due to increased the altitude of an object. binary code two states (on or off) levels of nutrients in a water system; astronomical unit (AU)is the that represent numbers and letters may occur seasonally or due to pollution distance from Earth to the Sun (150 binary compounds compounds made million km) of two elements Glossary • MHR 491 binary fission the splitting of a catalyst a substance that speeds up a colloids heterogeneous mixtures single-celled organism into two new chemical reaction without being used composed of fine particles evenly organisms approximately equal in up in a reaction distributed throughout a second size; amoebae and many bacteria caustic an agent that burns or substance reproduce asexually through this destroys living tissue combustion the highly exothermic process celestial bodies all objects seen combination of a substance with bioaccumulate to collect in progres- in the sky (the Sun, Moon, stars, oxygen; requires heat, oxygen, sively higher concentrations toward and planets) and fuel the top of the food chain cell the smallest unit that can commensalism a symbiotic biodegradable able to be broken perform the functions of life relationship between two different down by bacteria, fungi, and other types of organisms in which one of simple organisms into carbon cell wall a rigid structure surrounding the partners benefits and the other dioxide and water the cell membrane of plants, fungi, neither benefits nor loses and some unicellular organisms; bioindicator species species that protects and supports the cell community an association of different help indicate environmental change populations of organisms in a particular charge coupled devices (CCDs) environment or geographic area biological diversity the number and devices that convert light signals into variety of organisms in an area electric signals in digital format commutator a part of the dynamo generator that serves to reverse the biological indicator a living organ- chemical change a change in which ism whose state is indicative of induced current as it changes direction, one or more new chemical substances making the current flow in only conditions in a particular are formed environment one direction chemical family a group of related compass a device used to measure an biomagnification the process whereby elements that have similar properties chemicals accumulate in the tissues of object’s azimuth. organisms along the food chain chemical formula a formula that competition the struggle among shows the number and types of atoms individual organisms for access to a bioreactor a tank containing bacteria in a molecule in appropriate conditions for biore- limited resource, such as a food or mediation to occur chemical property a characteristic of territory matter that describes how it reacts compounds pure substances that are bioremediation a method of using when undergoing a chemical change living organisms to break down com- made up of two or more (e.g., reaction of a substance with elements chemically combined plex, toxic substances into electricity) simpler, non-toxic ones together; can be broken down into chemical reaction a process in which elements again by chemical means biotechnology using or modifying a substance is changed into one or concept map a diagram comprising living organisms to make marketable more new substances products; sometimes involves genetic words or phrases in circles or boxes engineering chemistry the study of the properties and connecting lines; used to show of matter and the changes it undergoes various relationships among con- branch each current path in a cepts; can also contain references to chromosome in a cell, tightly packed parallel current; a parallel circuit has events, objects, laws, themes, class- strands of DNA visible under a light a series of branches connected side room activities, or other items or microscope during cell division by side patterns related to the concept chronic toxicity the ability of a broad niche the roles or characteris- conclusion an interpretation of the chemical to cause harm to an organ- tic activities filled by a generalist results of an experiment as it applies ism only after the chemical organism to the hypothesis being tested accumulates to a specific level after budding an asexual reproduction many exposures over time conductivity the ability of a sub- process in which a bud forms on stance to carry an electrical current an organism, grows, and eventually circle graph a circle divided into breaks away to become a new organ- sections (like pieces of a pie) to conductors materials that allow ism independent of the parent represent data; also called a pie chart charges to move freely; most metals are conductors circuit breaker acts as a switch and C safety device that can cut all power constellations groupings of stars coming into the home that form patterns, which appear like carbohydrate an organic objects and are given names (such as clone an identical copy of a nutrient made of carbon, hydrogen, Orion, the hunter) molecule, gene, cell, or entire organism and oxygen continuous variation in genetics, cogenerator systems electricity catalytic converter a device that traits that show a range of generating stations that produce encourages complete oxidation possibilities electricity and also supply during combustion thermal energy 492 MHR • Glossary control in a scientific experiment, a direct current (DC) current that egg female gamete; also, a develop- standard to which the results are flows in one direction only ing embryo enclosed in a shell or compared; often necessary in order discrete variation in genetics, inher- membrane and produced by animals to draw a valid conclusion; ensures a ited traits that have a limited number that do not give birth to live young fair test of variations, such as the ability or electric discharge the rebalancing of convex lens a lens that is thicker in inability to roll one’s tongue an unbalanced charge; felt as a shock the middle than around the edges; dissolving breaking up; forming or seen as a spark causes refracting light rays to con- a solution by mixing two or more electric generator a device that verge (come together) materials together converts mechanical energy into co-ordinate graph a grid that has diversity the differences or variety of electric energy data points named as ordered pairs of adaptations of living things electrical code the set of standards numbers (e.g.
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