First Nine Weeks Glossary

Chapter 1 Vocabulary

Adaptive bioengineering – engineering that results in a product or process that changes living organisms

Area – a measure of the size of a surface or a region

Assistive bioengineering – engineering that results in a product or process that helps living organisms but does not change them permanently

Bioengineering – the application of engineering to living things, such as humans and plants

Cost-benefit analysis – the process of determining whether the cost of doing something is worth the benefit provided

Data – any pieces of information acquired through observation or experimentation

Engineering – the process of creating technology

Engineering design process – the process engineers use to develop a new technology

Hypothesis – an explanation that is based on prior scientific research or observations and that can be tested

Law – a summary of many experimental results and observations; a law tells how things work

Mass – a measure of the amount of matter in an object

Meter – the basic unit of length in the SI (symbol, m)

Model – a pattern, plan, representation, or description designed to show the structure or workings of an object, system, or concept

Observation – the process of obtaining information by using the senses

Prototype – a test model of a product

Science – the knowledge obtained by observing natural events and conditions in order to discover facts and formulate laws or principles that can be verified or tested

Scientific methods – a series of steps followed to solve problems

Technology – the products and processes that are designed to serve our needs

Temperature – a measure of how hot (or cold) something is; specifically, a measure of the average kinetic energy of the particles in an object

Theory – an explanation that ties together many hypotheses and observations

Volume – a measure of the size of a body or region in three-dimensional space

Chapter 12 Vocabulary

Energy – the capacity to do work

Energy conversion – a change from one form of energy to another

Fossil fuel – a nonrenewable energy resource formed from the remains of organisms that lived long ago

Friction – a force that opposes motion between two surfaces that are in contact

Kinetic energy – the energy of an object that is due to the object’s motion

Law of conservation of energy – the law that states that energy cannot be created or destroyed but can be changed from one form to another

Mechanical energy – the amount of work an object can do because of the object’s kinetic and potential energies

Nonrenewable resource – a resource that forms at a rate that is much slower than the rate at which it is consumed

Potential energy – the energy that an object has because of the position, shape, or condition of the object

Renewable resource – a natural resource that can be replaced at the same rate at which the resource is consumed

Chapter 13 Vocabulary

Absolute zero – the temperature at which molecular energy is at a minimum (0 K on the Kelvin scale or -273.16°C on the Celsius scale)

Change of state – the change of a substance from one physical state to another

Convection – the transfer of thermal energy by the circulation or movement of a liquid or gas

Heat – the energy transferred between objects that are at different temperatures

Insulation – a substance that reduces the transfer of electricity, heat, or sound

Radiation – the transfer of energy as electromagnetic waves

Specific heat – quantity of heat required to raise a unit mass of homogeneous material 1 K or 1°C in a specified way given constant pressure and volume

States of matter – the physical forms of matter, which include solid, liquid, and gas

Temperature – a measure of how hot (or cold) something is; specifically, a measure of the average kinetic energy of the particles in an object

Thermal conduction – the transfer of energy as heat through a material

Thermal conductor – material through which energy can be transferred as heat

Thermal energy – the kinetic energy of a substance’s atoms

Thermal insulator – a material that reduces or prevents the transfer of heat

Second Nine Weeks Glossary

Chapter 14 Vocabulary

Cell – in electricity, a device that produces an electric current by converting chemical or radiant energy into electrical energy

Electric current – the rate at which charges pass through a given point; measured in amperes

Electrical conductor – a material in which charges can move freely

Electrical insulator – a material in which charges cannot move freely

Parallel circuit – a circuit in which the parts are joined in branches such that the potential difference across each part is the same

Resistance – in physical science, the opposition presented to the current by a material or device

Series circuit – a circuit in which the parts are joined one after another such that the current in each part is the same

Static electricity – electric charge at rest; generally produced by friction or induction

Voltage – the potential difference between two points; measured in volts

Chapter 5 Vocabulary

Coriolis effect – the apparent curving of the path of a moving object from an otherwise straight path due to the Earth’s rotation

Deep current – a stream-like movement of ocean water far below the surface

Ocean current – a movement of ocean water that follows a regular pattern

Surface current – a horizontal movement of ocean water that is caused by wind and that occurs at or near the ocean’s surface

Tsunami – a giant ocean wave that forms after a volcanic eruption, submarine earthquake, or landslide

Chapter 6 Vocabulary

Air pressure – the measure of the force with which air molecules push on a surface

Atmosphere – a mixture of gases that surrounds a planet or moon

Convection – the transfer of thermal energy by the circulation or movement of a liquid or gas

Jet stream – a narrow belt of strong winds that blow in the upper troposphere

Radiation – the transfer of energy as electromagnetic waves

Wind – the movement of air caused by differences in air pressure

Chapter 7 Vocabulary

Air mass – a large body of air where temperature and moisture content are similar

Anemometer – an instrument used to measure wind speed

Anticyclone – the rotation of air around a high-pressure center in the direction opposite to Earth’s rotation

Barometer – an instrument that measures atmospheric pressure

Condensation – the change of state from a gas to a liquid

Cyclone – an area in the atmosphere that has lower pressure than the surrounding areas and has winds that spiral toward the center

Front – the boundary between air masses of different densities and usually different temperatures

Humidity – the amount of water vapor in the air

Hurricane – a severe storm that develops over tropical oceans and whose strong winds of more than 120 km/h spiral in toward the intensely low-pressure storm center

Precipitation – any form of water that falls to the Earth’s surface from the clouds

Relative humidity – the ratio of the amount of water vapor in the air to the maximum amount of water vapor the air can hold at a set temperature

Thermometer – an instrument that measures and indicates temperature

Thunderstorm – a usually brief, heavy storm that consists of rain, strong winds, lightning, and thunder

Tornado – a destructive, rotating column of air that has very high wind speeds, is visible as a funnel-shaped cloud, and touches the ground

Weather – the short-term state of the atmosphere, including temperature, humidity, precipitation, wind, and visibility

Chapter 10 Vocabulary

Day – the time required for Earth to rotate once on its axis

Eclipse – an event in which the shadow of one celestial body falls on another

Equinox – the moment when the sun appears to cross the celestial equator

Neap tide – a tide of minimum range that occurs during the first and third quarters of the moon

Phase – the change in the sunlit area of one celestial body as seen from another celestial body

Solstice – the point at which the sun is as far north or as far south of the equator as possible

Spring tide – a tide of increased range that occurs two times a month, at the new and full moons

Tidal range – the difference in levels of ocean water at high tide and low tide

Tide – the periodic rise and fall of the water level in the oceans and other large bodies of water

Third Nine Weeks Glossary

Chapter 8 Vocabulary

Black hole – an object so massive and dense that even light cannot escape its gravity

Galaxy – collection of stars, dust, & gas bound together by gravity

Light-year – the distance that light travels in one year; about 9.46 trillion kilometers

Nebula – a large cloud of gas and dust in interstellar space; a region in space where stars are born or where stars explode at the end of their lives

Neutron star – a star that has collapsed under gravity to the point that the electrons and protons have smashed together to form neutrons

Open cluster – a group of stars that are close together relative to surrounding stars

Pulsar – a rapidly spinning neutron star that emits rapid pulses of radio and optical energy

Quasar – a very luminous, star like object that generates energy at a high rate; quasars are thought to be the most distant objects in the universe

Supernova – a gigantic explosion in which a massive star collapses and throws its outer layers into space

Chapter 9 Vocabulary

Astronomical unit – the average distance between the Earth and the sun; approximately 150 million kilometers (symbol, AU)

Terrestrial planet – one of the highly dense planets nearest to the sun; Mercury, Venus, Mars, and Earth

Gas giant – a planet that has a deep, massive atmosphere, such as Jupiter, Saturn, Uranus, or Neptune

Satellite – a natural or artificial body that revolves around a planet

Comet – a small body of ice, rock, and cosmic dust that follows an elliptical orbit around the sun and that gives off gas and dust in the form of a tail as it passes close to the sun

Asteroid – a small, rocky object that orbits the sun, usually in a band between the orbits of Mars and Jupiter

Asteroid belt – the region of the solar system that is between the orbits of Mars and Jupiter and in which most asteroids orbit

Meteoroid – a relatively small, rocky body that travels through space

Meteorite – a meteoroid that reaches the Earth’s surface without burning up completely

Meteor – a bright streak of light that results when a meteoroid burns up in the Earth’s atmosphere

Chapter 2 Vocabulary

Abiotic – describes the nonliving part of the environment, including water, rocks, light, and temperature

Biosphere – the part of Earth where life exists

Biotic – describes living factors in the environment

Carnivore – an organism that eats animals

Carrying capacity – the largest population that an environment can support at any given time

Commensalism – a relationship between two organisms in which one organism benefits and the other is unaffected

Community – all of the populations of species that live in the same habitat and interact with each other

Ecology – the study of the interactions of living organisms with one another and with their environment

Ecosystem – a community of organisms and their abiotic, or nonliving, environment

Energy pyramid – a triangular diagram that shows an ecosystem’s loss of energy, which results as energy passes through the ecosystem’s food chain

Food chain – the pathway of energy transfer through various stages as a result of the feeding patterns of a series of organisms

Food web – a diagram that shows the feeding relationships between organisms in an ecosystem

Herbivore – an organism that eats only plants

Mutualism – a relationship between two species in which both species benefit

Omnivore – an organism that eats both plants and animals

Parasitism – a relationship between two species in which one species, the parasite, benefits from the other species, the host, which is harmed

Population – a group of organisms of the same species that live in a specific geographical area

Predator – an organism that eats all or part of another organism

Prey – an organism that is killed and eaten by another organism

Symbiosis – a relationship in which two different organisms live in close association with each other

Fourth Nine Weeks Glossary

Chapter 4 Vocabulary

Biome – a large region characterized by a specific type of climate and certain types of plant and animal communities

Savanna – a grassland that often has scattered trees and that is found in tropical and subtropical areas where seasonal rains, fires, and drought happen

Desert – an area that has little or no plant life, long periods without rain, and extreme temperatures; usually found in hot climates

Tundra – a treeless plain found in the Arctic, in the Antarctic, or on the tops of mountains that is characterized by very low winter temperatures and short, cool summers

Littoral zone – the shallow zone of a lake or pond where light reaches the bottom and nurtures plants

Open-water zone – the zone of a pond or lake that extends from the littoral zone and that is only as deep as light can reach

Deep-water zone – the zone of a lake or pond below the open-water zone, where no light reaches

Wetland – an area of land that is periodically underwater or whose soil contains a great deal of moisture

Marsh – a treeless, wetland ecosystem where plants such as grasses grow

Swamp – a wetland ecosystem in which shrubs and trees grow