SCIENCE EXAM SEMESTER 1

4 Earth systems

atmosphere, biosphere, lithosphere, hydrosphere

4 Steps to natural selection

1. Variation, 2. Selection pressures, 3. Fittest traits survive, 4. Reproduction

Abiotic factor

Non living parts of an ecosystem

Acceleration

change in velocity over time

Acquired trait

A trait which is gained during one's lifetime

Adaptation

A trait that helps an organism survive and reproduce

Albedo

Ability of a surface to reflect light

Biodiversity

the variety of life in the world or in a particular habitat or ecosystem.

Biodiversity

Variety of plants and animal life

Biotic factor

A living part of an ecosystem

Displacement

Distance and direction of an object's change in position from the starting point.

Distance

The length of a path between two points

Doppler effect

An observed change in the frequency of a wave when the source or observer is moving

Electromagnetic spectrum

Radiowave, Microwave, Infrared, Visible, UV ray, X ray, Gamma Ray

Evolution

Change in a kind of organism over time; process by which modern organisms have descended from ancient organisms.

Galaxy

A collection of stars, dust, and gas bound together by gravity

Genetic trait

a trait which is passed down from parent to offspring

Greenhouse effect

warming that results when solar radiation is trapped by the atmosphere

Greenhouse gases

Water vapor, methane, carbon dioxide

Life cycle of a large star

Nebula, protostar, main sequence star, red supergiant, supernova, neutron star or blackhole

Life cycle of a regular star

nebula, protostar, main sequence star, red giant, planetary nebula, white dwarf, black dwarf

Light year

The distance that light travels in one year

Moon

a natural object that orbits a planet

Mutation

A change in the genes in the DNA which can cause different traits to be expressed

natural selection

A natural process resulting in the evolution of organisms best adapted to the environment.

Planet

a celestial body that orbits the sun, is round because of its own gravity, and has cleared the neighborhood around its orbital path

Redshift

shift of light to a longer wavelength as it moves away

Scalar

A physical quantity that has magnitude only

Selection pressure

Pressures which affects an organism's ability to survive and reproduce

Speed

How fast something is going

Star

A self-luminous celestial body consisting of a mass of gas held together by its own gravity in which the energy is generated by nuclear reactions in its interior.

Sun

The star at the center of our solar system

The big bang theory

The theory that the universe originated in a huge explosion that released all matter and energy.

Variation

Difference in characteristics, traits or genetic sequences between individuals in the same species

Vector

A quantity that has magnitude and direction

Velocity

the speed of an object in a particular direction

Ecosystem

An environment where organisms interact and their physical environment

Lithosphere

the solid, outer layer of the earth that consists of the crust and the rigid upper part of the mantle

Biosphere

the part of Earth where life exists

Atmosphere

A thin layer of gases surrounding Earth