21.   At the United Nations, Waldheim is remembered as one of the least impressive and most unpopular secretaries-general the body has had.

22.   Because your body has never had to fight this hard, but it might.

23.   Biologists have believed until recently that each tissue in the body has its own dedicated source of stem cells that repair just that tissue.

24.   Bodies have had to work double shifts.

25.   Both children have almost no leptin, the hormone that normally signals when the body has enough fat and suppresses appetite.

26.   Both bodies have a responsibility to get on with the job.

27.   Both he and Humphrey said the body had several pieces of cardboard wrapped around it with some kind of tape.

28.   A. The human body has much better defenses against manipulating its DNA than we thought it had.

29.   After that, her body had other ideas.

30.   After this next birth, she thinks her body will have had enough.