https://www.khanacademy.org/science/grade-6-science-tx/x6eddf2e1c524bf5a:earth-s-systems-and-structure 2026-06-30T21:40:41.000025973Z Earth's systems and structure Identify and compare Earth's four major systems—the atmosphere, biosphere, geosphere, and hydrosphere—and the unique characteristics of each. Then, examine the layers that make up Earth's interior, from the crust to the inner core. Finally, learn how rocks form and transform through geologic processes in the rock cycle. unit