Unit 9, Topic 1: Life on Earth Vocabulary

atmosphere

• the gases surrounding earth, or another planet

• a layer of water vapor in the sky

• the surface of the earth

• a type of weather pattern

life

• any system capable of performing functions such as eating, metabolizing, excreting, breathing, moving, growing, reproducing, and responding to external stimuli

• a state of being that includes consciousness and self-awareness

• the biological process of growth and reproduction

• a collection of cells that can only exist in a controlled environment

planet

• a large celestial body that revolves around a star in a fixed orbit, reflecting light from that star

• a small rock that orbits a planet

• a type of star that emits its own light

• a celestial body that does not orbit any star

sphere

• a layer or system that makes up part of the earth

• a solid figure with all points equidistant from the center

• a flat, two-dimensional shape

• a type of celestial body

inhabitable

• suitable to live in; habitable

• unfit for living; barren

• dangerous to inhabit; toxic

• unpleasant and uncomfortable

solar system

• a group of planets and other bodies that revolve around a star

• a collection of stars in a galaxy

• a type of solar energy technology

• a planetary system with no stars

hydrosphere

• the regions on the surface of the earth that contain water such as lakes, seas, and rivers

• the layer of gases surrounding the planet

• the solid outer part of the earth

• the area of the earth that supports life

uninhabitable

• suitable for living in

• unsuitable for living in

• a place with abundant resources

• a location with high population density

system

• a group of parts that work together as a whole

• a single component that functions independently

• a collection of unrelated items

• a method of organizing information

lithosphere / geosphere

• the earth itself including rocks, minerals, and landforms of the surface and interior

• the layer of gases surrounding the planet

• the liquid layer of the earth beneath the crust

• the outermost layer of the earth's atmosphere