M3 Science Terms

Front 1

Absorption

Back 1

process by which food that has already been broken down passes through the walls of the intestine into the bloodstream

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acid

Back 2

substance that has a pH less than 7 when it is in aqueous solution

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acid leaching

Back 3

process in which acids dissolve metals found in soil; as the pH falls, heavy metas begin to dissolve

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acid precipitation

Back 4

rain, snow, fog, or dew that has a pH less than 5.6

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acid-base indicator

Back 5

substance that changes colour in the presence of an acid or a base

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additive colour theory

Back 6

theory oflight stating that white light is composed of different colours (wavelengths) of light

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albedo

Back 7

percent of incoming solar radiation reflected by a surface

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alkali metal

Back 8

member of the family of elements composed of soft, silver-grey metals that react easily with water and with oxygen in the air; group 1 on the periodic table

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alkaline earth metal

Back 9

member of the family of elements composed of silver-grey metals that are harder and more reactive than alkali metals; group 2 on the periodic table

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amplitude

Back 10

wave height from the rest position to the crest, or wave depth fromthe rest position to the trough; the larger the amplitude, the more energy that is carried

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anaphase

Back 11

third phase of mitosis; phase in which the sister chromatids separate into individual chromosomes and move to opposite poles

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angle of incidence (i)

Back 12

angle between the incident ray and the normal

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angle of reflection (r)

Back 13

angle between the reflected ray and the normal

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anthropogenic greenhouse effect

Back 14

enhancement of the natural greenhouse effect due to increased greenhouse gas emissions caused by human activities

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aperture

Back 15

in a camera, opening that the light passes through

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apoptosis

Back 16

controlled death of a cell that is no longer useful

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astigmatism

Back 17

condition in which the eye is unable to form a clear image because of an irregularly shaped cornea or lens

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atmosphere

Back 18

layer of gases that extends outward about 300 km from the surface of Earth

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atom

Back 19

smallest particle in matter

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atomic mass

Back 20

measure of the average mass of an atom of an element

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atomic number

Back 21

number of protons in an atom of an element

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atomic theory

Back 22

study of the nature of atoms and how atoms combine to form all types of matter

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axis of symmetry

Back 23

imaginary vertical line drawn through the optical centre of a lens

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base

Back 24

substance that has a pH greater than 7 when it is in aqueous solution

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binoculars

Back 25

two short refracting telescopes attached together

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bioluminescence

Back 26

ability of a plant or animal to produce light

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biome

Back 27

large geographical region with a defined climate (range of temperature and precipitation)

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biosphere

Back 28

relatively thin layer of Earth that has conditions suitable for supporting life; includes the lithosphere, hydrosphere, and atmosphere

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blind spot

Back 29

place where the optic nerve attaches to the retina

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Bohr diagram

Back 30

illustration of an atom that shows the arrangement and number of electrons in each shell

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boiling point

Back 31

(condensation point) temperature of boiling (or condensing)

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camera

Back 32

lightproof box with a lens at one end to form a real, inverted image on a light detector or on a light-sensitive plate or film

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cancer cell

Back 33

cell that divides uncontrollably; develops when a mutation occurs in the cell that affects how that cell divides

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capillary

Back 34

thin-walled blood vessel

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carbon footprint

Back 35

total amount of greenhouse gas emissions caused directly and indirectly by an individual, community, industry, or country

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carbon offset

Back 36

contribution of money to a carbon sink to compensate for an individual's or company's greenhouse gas emissions

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carbon sink

Back 37

process that takes carbon dioxide from the atmosphere and stores it

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carbon source

Back 38

process that releases carbon dioxide from the atmosphere and stores it

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carbon tax

Back 39

charge to an individual or company for creating greenhouse gas emissions either directly or by purchasing a fossil fuel

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cell

Back 40

basic unit of life for all living things

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cell cycle

Back 41

repeating cycle of events in the life of a cell in which it grows and prepares for division

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cell membrane

Back 42

protective barrier formed around every cell; made of a double layer of lipids

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cell specialization

Back 43

process in which cells develop in different ways to perform particular functions

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cell wall

Back 44

rigid frame around a plant cell that provides strength, protection, and support

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centriole

Back 45

pair of structures involved in cell division in animal cells

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chemical change

Back 46

transformation of one or more substances into new substances with new properties

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chemical equation

Back 47

words, or symbols and formulas, that describe the changes that occur during a chemical reaction

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chemical property

Back 48

property related to the ability of a substance to change into a new substance or substances

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chemical reaction

Back 49

process by which chemical change happens; all chemical reactions are also accompanied by changes in energy

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chemiluminescence

Back 50

light produced from a chemical reaction without a rise in temperature

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chloroplast

Back 51

organelle that contains a green substance called chlorophyll; found only in plant cells and some algae

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chromosome

Back 52

long piece of coiled DNA and proteins; only visible during mitosis

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circulatory system

Back 53

organ system that includes the heart, blood, veins, arteries, and capillaries; transports blood around the body

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climate

Back 54

average weather conditions that occur in a region over a long period of time, usually a minimum of 30 years

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climate change

Back 55

significant long-term change in expected climate patterns

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cloning

Back 56

creation of a genetically identical organism that is an exact copy of a gene, cell, tissue, or organism

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colour blindness

Back 57

ability to see only shades of grey; very rare, occurring in about 1 in 40 000 people

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colour vision deficiency

Back 58

ability to distinguish some colours but not others

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combustion

Back 59

chemical reaction in which a compound or element rapidly combines with oxygen gas

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compound

Back 60

pure substance made from two or more elements that are combined together chemically

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compound microscope

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type of light microscope in which a pair of convex lenses causes a small object to appear magnified when viewed through the eyepiece

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concave lens

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lens that is thinner at the centre than at the edges; also called a diverging lens

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concave mirror

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reflecting surface that curves inward like a bowl; also called a converging mirror

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concentration

Back 64

amount of a substance that has been dissolved in a solution

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conduction

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transfer of thermal energy through direct contact between the particles of a substance without moving the particles to a new location

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conductivity

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ability to conduct hear or electricity

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cone cells

Back 67

photoreceptor cells in the eye that detect colour

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confidence level

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degree of confidence in predictions about a particular event

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convection

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transfer of thermal energy through the movement of particles from one location to another

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converging lens

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lens that is thicker at the centre than at the edges; also called a convex lens

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converging mirror

Back 71

reflecting surface that curves inward like a bowl; also called a concave mirror

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convex lens

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lens that is thicker at the centre than at the edges; also called a converging lens

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convex mirror

Back 73

reflecting surface that curves outward; also called a diverging mirror

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Coriolis effect

Back 74

deflection of any object from a straight-line path by the rotation Earth

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cornea

Back 75

transparent layer of tissue on the outer surface of the eye covering the iris and pupil; refracts light entering the eye

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covalent bond

Back 76

connection, usually between the atoms of non-metals, in which the two atoms share a pair of electrons

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crest

Back 77

highest point in a wave

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crystal formation

Back 78

forming of particles with a crystalline appearance

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cytokinesis

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division of the cytoplasm during mitosis

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cytoplasm

Back 80

jelly-like substance that fills the cell and surrounds the organelles

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cytoskeleton

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internal network of fibres within a cell; made up of protein filaments

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decomposition reaction

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chemical reaction in which a compound is broken apart into two or more elements and/or simpler compounds

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diaphragm

Back 83

in a camera, an adjustable opening that controls the aperture

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diatomic molecule

Back 84

molecule made from two atoms

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differentiation

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process in which stem cells become specialized so that they can perform different functions

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diffuse reflection

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reflection in which parallel light rays are scattered in different directions when reflected from an irregular surface

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diffusion

Back 87

process for moving substances across a cell membrane

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digestive system

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organ system made up of the mouth, esophagus, stomach, small and large intestines, and rectum; transports and absorbs nutrients in the body

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dispersion

Back 89

refraction of white light into separate wavelengths, or colours

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diverging lens

Back 90

lens that is thinner at the centre than at the edges; also called a concave lens

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diverging mirror

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reflecting surface that curves outward; also called a convex mirror

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DNA screening

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test in which DNA is analyzed to see if an individual has a series of genes related to certain diseases, such as heart disease and types of cancer

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double-displacement reaction

Back 93

chemical reaction in which the positive or negative ions in two dissolved ionic compounds switch places

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ductility

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ability to be stretched without breaking

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economic system

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organized way in which a country or region sets up activities related to how goods and services are produced, distributed, and consumed

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electric discharge

Back 96

method for producing light in which an electric current passes through the air or another gas

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electroluminescence

Back 97

process of transforming electrical energy directly into light energy

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electromagnetic radiation

Back 98

energy that can travel through empty space in the form of waves

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electromagnetic spectrum

Back 99

entire range of wavelengths or frequencies of electromagnetic radiation extending from the shortest gamma rays to the longest radio waves and including light

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electron

Back 100

subatomic particle that has a negative charge of 1-

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element

Back 101

substance that cannot be broken down into any simpler substance by chemical means

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emissions trading

Back 102

system by which a company that reduces its emissions by more than the government limit can trade the extra amount to another company that has exceeded its maximum; also called "cap and trade"

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esophagus

Back 103

tube that allows food to travel from the mouth to the stomach

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excretory system

Back 104

organ system that includes the kidneys, ureters, urinary bladder, urethra, and skin; filters waste products from the blood and maintains the proper levels of water and electrolytes in the body

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family

Back 105

vertical column of the periodic table; elements in the same family in the periodic table have similar physical and chemical properties; also called a group

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far-sighted

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able to see distant objects clearly but not near objects clearly

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fluorescent

Back 107

describes light emitted by some substances when they are exposed to electromagnetic radiation

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focal length

Back 108

distance from the vertex to the focal point of a curved mirror

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focal point

Back 109

point where the light rays meet or appear to meet

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formula equation

Back 110

chemical equation that uses formulas of the reactants and products

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fossil fuels

Back 111

hydrocarbons formed underground over millions of years from the remains of once-living organisms; fossil fuels are coal, oil, and natural gas

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frequency (f)

Back 112

rate of repetition of a wave; measured in hertz (Hz), which is cycles per second

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gamma rays

Back 113

extremely high-energy electromagnetic radiation that can penetrate human tissue

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gene

Back 114

each section of DNA that codes for a particular protein

Front 115

gene therapy

Back 115

therapy in which healthy genes are inserted into cells so that cells function normally

Front 116

general chemical equation (GCE)

Back 116

equation that uses letters of the alphabet (A, B, C, D) in place of symbols for elements

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geometric optics

Back 117

science of how light reflects and refracts

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global warming

Back 118

observed increases in Earth's average annual temperature

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global warming potential

Back 119

measure of the ability of a greenhouse gas to trap thermal energy in the atmosphere

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Golgi apparatus

Back 120

structure that receives proteins from the endoplasmic reticulum; modifies, sorts, and packages these proteins for delivery throughout the cell or outside the cell

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granum

Back 121

stack of thylakoids

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greenhouse gas

Back 122

gas that contributes to the natural greenhouse effect, such as water vapour, carbon dioxide, nitrous oxide, or methane; last three also contribute to the anthropogenic greenhouse effect

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group

Back 123

vertical column of the periodic table; elements in the same family in the periodic table have similar physical and chemical properties; also called a family

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halogen

Back 124

member of the family of elements composed of very reactive, coloured non-metals; group 17 on the periodic table

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heart

Back 125

muscular pump that supplies blood to all parts of the body

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heterogeneous mixture

Back 126

mixture in which different parts of the mixture are visible

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homeostasis

Back 127

tendency of an organism to maintain a steady state; an acceptable range of physical and chemical conditions in which body cells, tissues, and organs can operate efficiently

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homogeneous mixture

Back 128

mixture that looks the same throughout and the separate components are not visible; sugar water is a solution of sugar dissolved in water

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hydrocarbon

Back 129

compound made of only carbon and hydrogen

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hydrosphere

Back 130

includes all of the water on Earth, with about 97 percent of this water being salt water in the Earth's oceans

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image

Back 131

in optics, reproduction of an object seen in reflective surfaces such as calm water or glass

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immunization

Back 132

making a person resistant to infection through vaccination

Front 133

incandescent

Back 133

describes light produced by an object, such as a metal, that is very high temperature

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incident ray

Back 134

ray that strikes a reflecting or refracting surface

Front 135

index of refraction

Back 135

amount by which a transparent material decreases the speed of light; indicated by a number; also called refractive index

Front 136

infrared waves

Back 136

electromagnetic radiation that has wavelengths shorter than microwaves but longer than the visible spectrum

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insolation

Back 137

amount of solar energy received by a region of Earth's surface

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integumentary system

Back 138

organ system made up of skin and accessory structures

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interdependant

Back 139

connection between parts so that one part contributes to the action of another part; e.g., body systems are interdependant because the action of each system contributes to the actions of the other systems

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interphase

Back 140

stage in the cell cycle in which the cell grows and prepares for cell division

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intestine

Back 141

area of chemical digestion and removal of wastes

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ion

Back 142

atom or group of atoms with a negative charge or a positive charge

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ionic compound

Back 143

compound formed from one or more positively charged ion(s) and one or more negatively charged ion(s)

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iris

Back 144

circular coloured band of muscle in the eye that controls the size of the pupil and the amount of light that enters the eye

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Kyoto Protocol

Back 145

UNFCCC agreement among countries to reduce their greenhouse gas emissions

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laser

Back 146

light in which all the light rays are almost perfectly parallel, all have the same wavelength, and all wave crests and troughs are exactly lined up

Front 147

law of conservation of mass

Back 147

scientific law stating that the mass of the products always equals the mass of the reactants in a chemical reaction

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law of reflection

Back 148

scientific law stating that when light reflects off a surface, the angle of incidence always equals the angle of reflection; refers to the predictable behaviour of reflected light

Front 149

lens

Back 149

curved transparent object that is smooth and regularly shaped, so that when light strikes it, the light refracts in a predictable and useful way

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light-emitting diode (LED)

Back 150

electroluminescent light source made from a semiconductor

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liquid crystal

Back 151

solid that can change the orientation of its molecules like a liquid, but only when electricity is applied

Front 152

liquid crystal display (LCD)

Back 152

light source in which white light, such as a fluorescent light or light-emitting diode, shines behind a liquid crystal

Front 153

lithosphere

Back 153

solid portion of Earth that floats on the semi-fluid portion of the upper mantle

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lung

Back 154

one of a pair of organs involved in respiration