Little known fact: You can't harvest organs from someone who is already dead (i.e. a cadaver).
All organ harvesting must come from a live person, never from a cadaver.
Ah! I see where the confusion lies. I was referring to organ donation (as opposed to organ harvesting).
I was thinking of a live person freely donating a single unpaired organ, such as the case of a friend who still lives a very active life subsequent to donating one of his kidneys to his sister over 20 yrs ago. This case was not on my mind when I wrote the first post here.