11.   Beth Winslow studied human biology with an eye toward teaching aerobics, but now she runs the computer network for an Internet startup firm called iPass.

12.   But they said it was time for science to confront its growing powers to shape human biology.

13.   But what happens under artificial test conditions can be totally irrelevant to human biology.

14.   Charles Platt is a journalist specializing in advanced technology, computer science and human biology.

15.   He believed that an understanding of how cells work and other matters of human biology would lead to discoveries in all diseases.

16.   His surprise discovery helped pave the way to much work in human biology pertaining to chromosomal abnormalities.

17.   Human biology has been daunting in its complexity, and out of necessity, medical science is forced to simplify it in creating concepts of illness.

18.   It is a quirk of human biology that makes placental blood so rich in stem cells.

19.   Patenting such fundamental facets of human biology seems likely to become part of the debate.

20.   Remarkably, for such a longstanding and uniform feature of human biology, scientists are still not sure exactly what causes presbyopia or what might reverse it.