Question

SIAL and SIMA are the divisions of ________.
a.Lithosphere
b.Hydrosphere
c.Biosphere
d.None of these.

Answer 1

Hint: SIAL and SIMA are the notations used for Silico-Aluminium and the Silico-Magnesium layers present in the Earth. It is one of the most accessible layers of the Earth for excavation purposes and also provides the most important ores for human uses.

Complete Step by Step Answer: The question has three out of the four spherical divisions of the Earth. Let’s analyse the different options before reaching a conclusion.
a.Lithosphere: Lithosphere is the uppermost layer of a terrestrial planet or a natural satellite. It's defined by its rigid mechanical processes. On earth, the lithosphere is made of the crust and the upper mantle. Sial and Sima are lower layers of the crust, Sial being under land and Sima being under the ocean floor. It extends up to a depth of 60 kilometers below the surface of the Earth. So, it is the correct option.
b.Hydrosphere: Hydrosphere is defined as all the water on the planet. It includes Ocean, seas, rivers, lakes, other static and moving water bodies, clouds, water vapour and underground water. Water in any from - solid, liquid or ice- on the surface of earth is referred to as the Hydrosphere. So, it is an incorrect option.
c.Biosphere: Biosphere is an ecosystem on the global level. It is made up of biotic and abiotic components. Biosphere is the only sphere of the four spheres of environment where life exists. It is a junction of the lithosphere, hydrosphere and the atmosphere. So, it is an incorrect option.
d.None of these: Since we already have a correct option from the ones given above, this option is out of bounds. So, it is an incorrect option.

Note: In addition to Sial and Sima, there is another layer which is found in the core of the Earth and is known as the NiFe layer. It is made up of Nickel and Iron.