Why is type O negative blood considered the universal blood…

Why is type O negative blood considered the universal blood donor and type AB positive considered the universal blood recipient.  (you must use the words glycoprotein, agglutinin and agglutinogen where appropriate to receive full credit AND discuss both O and AB blood types). (to avoid any possible confusion/wasted effort- (I know it perplexed me) most transfusions are NOT whole blood but instead just the erythrocytes so material ins the plasma is less significant- so don’t explain that to me).

I celebrated my 50th birthday with a colonoscopy (actually o…

I celebrated my 50th birthday with a colonoscopy (actually on my birthday-sadness).  A colonoscopy is when you get to have severe diarrhea for a day to empty your bowels and a camera is inserted into your anus and threaded through your entire LARGE INTESTINE to look for anything suspicious (cancer, precancer nodules). In order (from the anus on in), what regions were viewed (by the doctor)?