Most one‑carbon transfers are promoted by one of three cofactors: biotin, tetrahydrofolate, or s‑adenosylmethionine. s‑adenosylmethionine is generally used as a methyl group donor; the transfer potential of the methyl group in n 5 ‑methyltetrahydrofolate is insufficient for most biosynthetic reactions. however, one example of the use of n 5 ‑methyltetrahydrofolate in methyl group transfer is in methionine formation by the methionine synthase reaction; methionine is the immediate precursor of s‑adenosylmethionine. list the three methyl donors in order of methyl group transfer potential highest to lowest.

What best explains whether bromine (br) or neon (ne) is more likely to form a covalent bond? bromine forms covalent bonds because it has seven valence electrons, but neon has eight valence electrons and already fulfills the octet rule. bromine forms covalent bonds because it has many electron shells, but neon has only two electron shells and is tightly bound to its electrons. neon forms covalent bonds because it can share its valence electrons, but bromine has seven valence electrons and can gain only one more electron. neon forms covalent bonds because it has only two electron shells, but bromine has many electron shells and will lose electrons in order to fulfill the octet rule.