[MHGinTN]

You are making the error of equating blood (a subunit of the organism) with the whole organism (as in an embryo is the organism, the whole person at the age of embryo).

... and(in vitro fertilization) the process redefined the earliest age of an individual’s lifetime as but one stage ‘in a process that eventually becomes a human being’. (That new definition arbitrarily chosen claimed the 'thing' eventually becomes a human being, but the prior truth had to be ignored in order to establish the new utilitarian definition.) The individual life begins at conception. The 'clock' of lifetime begins ticking at conception and each age of the individual is but an age along a continuum that is an individual's lifetime.

[Dave S]

You are making the error of equating blood (a subunit of the organism) with the whole organism (as in an embryo is the organism, the whole person at the age of embryo).

Then what's your problem with stem cells? Cells are just part of that glob of cells you call a human being at two weeks. Are you saying that taking a cell or two is equivalent to canibalism but that taking a pint of blood isnt?