1. UNIT 3: LESSON1 (EARTH’S SPHERES)

2. EARTH SYSTEM? Earth System: All of the matter, energy, and processes within Earth’s boundaries. Earth is a complex system of smaller systems, full living and non-living things. These smaller systems transfer energy and matter from one to another constantly

3. THE GEOSPHERE The mostly solid, rocky part of Earth  Crust: Thin, outermost layer of Earth. Made mostly of silicates.  Mantle: Dense layer of hot silicates (lava) between the Crust and Core.  Core: Most Dense layer of Earth comprised of Iron and Nickel.

4. THE HYDROSPHERE The portion of the Earth that is liquid water. 97% of liquid water is salt water in oceans The other three percent is in lakes, rivers and even living things.

5. THE CRYOSPHERE Made up of all the frozen water on Earth’s surface. Includes glaciers, snow, icebergs and any other occurrence where water ice naturally forms.

6. THE ATMOSPHERE Mixture of mostly invisible gases that surrounds Earth. The main gases that compose the atmosphere are Nitrogen (78%) and Oxygen (21%) and other gases (1%). The atmosphere traps heat from the sun, blocks out harmful UV rays, and provides breathable air.

7. THE BIOSPHERE Made up of living things and the areas of Earth where they are found. Life has been found in all corners of the globe from rain forests to thermal vents on the ocean floor. Energy sources such as sunlight or geothermal energy and Oxygen or Carbon Dioxide are necessary components for life to develop.

8. EARTH’S SPHERES INTERACT Energy and Matter transfer and cycle through the different spheres, whereby life becomes possible.

9. MATTER EXCHANGES BETWEEN SPHERES Matter changes spheres all the time in Earth Systems. Ex.) plant decomposition, water melting and freezing in polar regions

10. ENERGY EXCHANGES BETWEEN SPHERES Autotrophs use solar or geothermal energy to produce “food”