The lithosphere or the land sphere are the plates that are surface layers of the earth. And this lithosphere is made up of Silicon and Aluminium components. The Lithosphere is divided into upper and lower parts by the thick layers of sedimentary rocks.
It constitutes of hard, rigid and outer skins of earth. On lithosphere, the entire biosphere that's the life sphere is based. There are two types of lithosphere i.e oceanic and continental the oceanic has a <u>density of 2.9 grams, and crust on land has 2.7 grams</u>.
Composition Of oceanic lithosphere is of mafic and ultramafic. The asthenosphere is a layer that forms underneath this zone and is in liquid molten forms. This also divided into three zones the upper zone, transition zone, and lower zone.
Melting of rock mass takes place in this layer as it has a depth of 2900 km and the boundary is defined by stress zone that deforms easily and has elasticity. Most of the earthquake waves and lava plums come out of this zone. It's composed of heavier metals like Iron and Aluminium, nickel, etc.
Central America is a long and narrow strip of land which is located between two bodies of water and which connects two pieces of land - we call such a formation an "isthmus" - this is the correct answer.
The Suez canal is also such an isthmus and so is Manila, the capital of the Philippines.
