What is the relationship between the crust and the lithosphere? The earth is made up of 4 layers overlying each other; crust, mantle, outer core and inner core.
Crust is the Earths outermost part. This is where we live and plants grow. The crust is a thin compared to the other three layers. The crust is 32 Km (25 miles) thick. Below crust is another layer called moho and then below moho is another layer called the mantle. The mantle is around 1800 miles thick and is the largest of the others. Now Lithosphere is the combination of crust and the upper part of the mantle. The mantle is a dense semisolid mass. It is divided in to two parts; the upper layer and lower layer. The upper part of mantle is rigid like the crust and it is this part that is similar to crust. The upper layer and the crust is what is called lithosphere.
So, the lithosphere is both the crust as well as the very upper or top of the mantle. The crust is all part of the lithosphere, but the lithosphere is more than just the crust.
The outer core is 1400 miles thick and the inner core is about 800 miles thick.