Multiple choice Which sub type of vitamin K is synthesised by human tissues? Menaquinone-4 (MK-4) Menaquinone-7 (MK-7) Menaquinone-9 (MK-9) Menaquinone-8 (MK-8) Reveal answer Fill a bubble to check yourself B Correct answer Explanation Menaquinone-7 is not produced by human tissues. MK-7 may be converted from phylloquinone (K1) in the colon by E. coli bacteria.