ACTH is a segment of a much larger glycoprotein prohormone molecule called proopiomelanocortin (POMC). POMC is synthesized by the corticotrophs of the anterior pituitary, which constitute about 10 percent of the gland.
Caviar harvested from an older fish is the more rare, and more sought after, white caviar. The Beluga sturgeon are primarily found in the Caspian Sea, which is surrounded by Iran, Azerbaijan, Russia, Kazakhstan and Turkmenistan. The other primary source of Beluga sturgeon is the Black Sea near Russia and Romania.
Where the name came from. Contrary to popular belief, the term caviar does not originate from Russia. (If that is the case, we should be calling it ikra instead of caviar.) The terms caviarie and caviare does have its etymological origin from a Turkish term havyar. This, in turn, came from an Iranian form khayah.