[SunStar]

Thanks.

The key phrase in your post is the following:

"Human life is defined by the ability to function as an integrated whole, not by mere presence of living human cells."

The first 8 weeks of a pregnancy (at a minimum) consist of the mere presence of living human cells.

[MHGinTN]

The first 8 weeks of a pregnancy (at a minimum) consist of the mere presence of living human cells. SunStar You apparently missed the point. Your comment is decidedly incorrect since the earliest age of an lindividual's lifetime evidences an ORGANISM acting as an integrated whole. You wish to focus upon the organ(s) as the essence of the ORGANISM. The early embryo is exactly viable as an ORGANISM living as an integrated whole, building its own placenta and body for future survival when it grows too large for the 'water-world' of the uterine environment and must exit to the 'air-world'. The embryo is far more than 'mere presence of living human cells' since those cells--the stem cells--are the body parts of a coherent, integrated ORGANISM functioning as a coordinated whole.