By Prof. Liwayway Memije-Cruz

The surface of the earth is divided into four inter-connected  spheres called "geo-spheres".

These are the lithosphere, hydrosphere, biosphere, and atmosphere. Geologists, scientists and researchers discovered and classified life and material on or near the surface of the earth in these four spheres. The four spheres derived its names from the Greek words litho for stone, atmo for air,  hydro  for water and bio for life.