Oceanography Chapter 1

Front 1

Accretion

Back 1

An increase in the mass of a body by accumulation or clumping of smaller particles.

Front 2

Animal

Back 2

A multicellular organism unable to synthesize its own food and often capable of movement.

Front 3

Atom

Back 3

The smallest particle of an element that exhibits the characteristics of that element.

Front 4

Big Bang

Back 4

The hypothetical event that started the expansion of the universe from a geometric point; the beginning of time.

Front 5

Biosynthesis

Back 5

The initial formation of life on Earth.

Front 6

Cell

Back 6

The basic organizational unit of life on this planet.

Front 7

Compound

Back 7

A substance composed of two or more elements in a fixed proportion.

Front 8

Condensation Theory

Back 8

Premise that stars and planets accumulate from contracting, accretion clouds and galactic gas, dust, and debris.

Front 9

Density Stratification

Back 9

The formation of layers in a material, with each deeper layer being denser (weighing more per unit of volume) than the layer above.

Front 10

Element

Back 10

A substance composed of identical atoms that cannot be broken down into simpler substances by chemical means.

Front 11

Experiments

Back 11

Tests that simplify observation in nature or in the laboratory by manipulating or controlling the conditions under which observations are made.

Front 12

Galaxy

Back 12

A large rotating aggregation of stars, dust, gas, and other debris held together by gravity. There are perhaps 50 billion galaxies in the universe and 50 billion stars in each galaxy.

Front 13

Hypothesis

Back 13

A speculation about the natural world that may be verified or disproved by observation and experiment.

Front 14

Law

Back 14

A large construct explaining events in nature that have been observed to occur with unvarying uniformity under the same conditions.

Front 15

Marine Science

Back 15

A process (or result) of applying the scientific method to the ocean, its surroundings, and the life-forms within it; also called oceanography or oceanology.

Front 16

Mass

Back 16

A measure of the quanity of matter.

Front 17

Membrane

Back 17

A complex structure of proteins and lipids that forms boundaries around and within a cell. It is usually semipermeable, allowing some kinds of molecules to pass through but not others.

Front 18

Milky Way Galaxy

Back 18

The name of our galaxy; sometimes applied to the field of stars in our home spiral arm, which is correctly called the Orion arm.

Front 19

Mixture

Back 19

A close intermingling of different substances that still retain separate identities. The properties of a mixture are heterogeneous; they may vary within the mixture.

Front 20

Nebula

Back 20

Diffuse cloud of dust and gas.

Front 21

Nonconservative Constituent

Back 21

An element whose proportion in seawater varies with time and place, depending on biological demand or chemical reactivity. An element with a short residence time; for example, iron, aluminum, silicon, trace nutrients, dissolved oxygen, and carbon dioxide.

Front 22

Nonconservative Nutrient

Back 22

A compound or ion that is needed by autotrophs for primary productivity and that changes in the concentration with biological activity.

Front 23

Ocean

Back 23

(1) The great body of saline water that covers 70.78% of the surface of Earth. (2) One of its promary subdivisions, bounded by continents, the equator, and other imaginary lines.

Front 24

Oceanography

Back 24

The science of the ocean. See also Marine Science.

Front 25

Outgassing

Back 25

The volcanic venting of volatile substances.

Front 26

Oxygen Revolution

Back 26

The time span, from about 2 billion years to 400 million years ago, during which photosynthetic autotrophs changed the composition of the Earth's atmosphere to its current oxygen-rich mixture.

Front 27

Photon

Back 27

The smallest unit of light energy.

Front 28

Planet

Back 28

A smaller, usually nonluminous body orbiting a star.

Front 29

Protostar

Back 29

A tightly condensed knot of material that has not yet attained fusion temperature.

Front 30

Science

Back 30

A systematic way of asking questions about the natural world and testing the answers to those questions.

Front 31

Scientific Method

Back 31

The orderly process by which theories explaining the operation of the natural world are verified or rejected.

Front 32

Solar Nebula

Back 32

The diffuse cloud of dust and gas from which the solar system originated.

Front 33

Solar System

Back 33

The sun together with the planets and other bodies that revolve around it.

Front 34

Star

Back 34

A massive sphere of incandescent gases powered by the conversion of hydrogen to helium and other heaver elements.

Front 35

Supernova

Back 35

The explosive collapse of a massive star.

Front 36

Synoptic Sampling

Back 36

Simultaneous sampling at many locations.

Front 37

Theory

Back 37

A general explanation of a characteristic of nature consistently supported by observation or experiment.

Front 38

World Ocean

Back 38

The great body of saline water that covers 70.78% of Earth's surface.