Glycolysis represents only very limited oxidation of glucose into pyruvate, and may be followed up by fermentation involving reduction of pyruvate, not further oxidation. Explain how one molecule of NAD plays important roles in both parts of the these reactions, specifically mentioning how it is involved in both oxidation and reduction.

answer is: naturally occurring solid, inorganic compound or element is mineral.

minerals usually have crystalline form, that means than crystal constituents (atoms, molecules or ions) are arranged in a highly ordered microscopic structure, forming a crystal lattice that extends in all directions.

for example magnetite is a mineral of iron oxide (fe₂o₃).

calcite is a carbonate mineral and the most stable polymorph of calcium carbonate (caco₃).

dolomite is an   carbonate mineral composed of calcium magnesium carbonate (camg(co₃)₂).