Marine stickleback populations live and breed strictly in the ocean. Sea-run stickleback fish are. anadromous, meaning that they are born in fresh water, spend most of their lives in the ocean, and. return to fresh water to breed. Freshwater stickleback fish live entirely in fresh water.
Among patients with Crohn's disease, 4% will have an anal fissure as the first manifestation of their Crohn's disease, and half of all patients with Crohn's disease eventually will develop an anal ulceration that may look like a fissure.
Knowledge center. An anal fissure is an anal tear, crack or ulcer in the lining of the anal canal-a cut or tear in the anus that extends into the anal canal.It is a common cause of red blood in the stool (feces) and toilet paper.nowledge center. An anal fissure is an anal tear, crack or ulcer in the lining of the anal canal-a cut or tear in the anus that extends into the anal canal.