Can you let me know is irritable bowel syndrome and diverticulosis the same thing?

NO: Diverticulosis is the outpouching that occurs on the colon, usually the sigmoid, of first world people. Primarily due to a higher fat, lower fibre diet. Ibs is a non-defined collection of symptoms, where no definitive cause is identified. It's not a "disease" in the truest sense, and neither is diverticulosis, which is a description of the colon wall. Good luck.

Structure/Function.: Diverticulosis is an issue with the formation of outpouchings in the colon which can bleed or become infected. IBS is considered a functional issue, a hypersensitivity of the intestines to normal stimuli.