This is how I study medicine. I find boring things and turn them into this shit to make them easy to study.
This is the story of how Vitamin D was perverted into its present form. Once, long ago, The 7th (7-dehydrocholesterol) led a happy life. It lived peacefully in the skin, minding its own business and going about its own dehydro duties. Then, misfortune struck, for her virtue brought her to the attention of the Heavens and UV light sought to marry her.
"Nay, I am sworn to celibacy, Your Brightness" The 7th said.
"But I will make you Queen of the Heavens," said UV, trying to grab her.
The 7th fled in fright and this rejection so angered The Great UV that he cursed her, condemning her to be stripped of her titles, and because she rejected him she would now be available to everyone, hence she was renamed Cal Fer All (Cholecalciferol/D3).
Cal Fer All was pushed out into the strange world of The Blood where she was buffeted about by all manner of twisted things rushing by. Finally, a blood cell took pity on her and took her to The Liver in the hopes that the Great Modifier might have a solution.
But this hope backfired for The Liver's response was something along the lines of, "Wha'chu talkin' about nigga? Can an'body understan' a thang of what this here gal is sayin'? Throw out this motha'fucka"
The Liver's guard, 25-Hydroxylase was ordered to escort out Cal Fer All, but because the guard was a pervert and because she had been declared Fer All, 25-Hydroxylase dragged her to a corner, had his way with her to the extent that she took on his name as her own and pushed her back into The Blood. Cal Fer All, now renamed 25-hydroxy Cal Fer All (25-Hydroxycholecalciferol) went weeping to the kidney where useless things like her were destined. But The Kidney, being a great fortune teller, saw that 25-Hydroxy Cal Fer All still had a use in the body and order his guard 1-alpa Hydroxylase to throw her back in The Blood. But this 1-alpha Hydroxylase, considering himself a great, virile alpha and being brother to the pervert 25-Hydroxylase, also dragged 25-Hydroxy Cal Fer All into a corner and then pushed her back into The Blood. Now known as 1,25-dihydroxy Cal Fer All, her nature had been completely changed. Gone was the sweet child of the skin. In its place was a monster, who perceiving that her second name Calcitriol suggested three Cals, set about finding someone else to share in the trio of misery. Her eye fell on Calcium and Phosphate, setting up house in the Bone and later trying to escape in the intestine. She dragged them, kicking and screaming, back into The Blood and there they drift to this day.