Cyanocobalamin is the most common and widely produced form of the chemical compounds that have vitamin B12 activity.
For example, the hadron constituents of atomic nuclei, neutrons and protons, have charges of 0 e and +1 e respectively; the neutron is composed of two down quarks and one up quark, and the proton of two up quarks and one down quark.
Only the up and down quarks are needed to make protons and neutrons; the others occur in heavier, unstable particles. Quarks are any of a group of subatomic particles thought to be among the fundamental constituents of matter more specifically, of protons and neutrons. <br /> The concept of the quark was first proposed by Murray Gell-Mann and George Zweig ; its name was taken from James Joyce's novel Finnegans Wake.