<span>Rocks can best be identified by their mineral content. This is
because rocks are composed of one or multiple numbers of minerals. Quartz,
calcite, feldspars, and micas are examples of minerals that make rock formations
possible.
Rocks are the basic component of the Earth's crust. Mountains, hills, and
volcanoes are examples of rock formations that occur through time on Earth. One
can find rocks all over the Earth and most are usually under the soil. Rocks
can be further classified as igneous, sedimentary, or metamorphic rocks.</span>
I believe the answer is comparative anatomy. It is the study of the similarities and differences in the structures of different species. Similar body parts may be homologies or analogies, such that both provide evidence of evolution. Similarities in embryos are evidence of common ancestry. For example all vertebrates embryos have gill slits and tails.
The nutrients that coats your nerves is something called myelin. Those like vitamin B and D can help out myelin sheath.
