Symbolism, Imagery, Allegory
There are very few pictures of Henrietta and her lost child, which makes them precious to the family and of special significance to their stories. In Henrietta's case, there's only one of her standing on her own. The appearance of this picture in textbooks about genetics and on the cover of Skloot's book emphasizes the humanity of the woman behind all the science.
And that's exactly what it's meant to do: re-humanize HeLa cells so that the world isn't tempted to value the scientific research over the life that was lost and made it all possible.
There are also two pictures of Elsie that figure prominently in the book. The first is the picture of her when she was at home, being cared for by her mother. That's the picture that everyone "oohs" and "aahs" over, since Elsie was a loved and beautiful child. But the second picture—the Crownsville picture—is the one that carries some heavy weight:
Her once-beautiful eyes bulge from her head, slightly bruised and almost swollen shut...her face misshapen and barely recognizable, her nostrils inflamed and ringed with mucus...Her head is twisted unnaturally to the left, chin raised and held in place by a large pair of white hands. (273)
Skloot and Deborah know that this is not okay. The picture of Elsie represents not only the abuse that she personally endured at the hands of doctors and nurses at Crownsville, but the thousands of black men, women and children who also suffered there; powerless people who were more or less tortured so researches could learn about the brain.
The white hand reminds Skloot and Deborah of the mostly white medical community that didn't always have the best interests of the patients at heart, especially when scientific research, and profits were at stake. Deborah reads that right away from the photo of Elsie.
The photos sum up Skloot's reason for writing the book: there are people behind these scientific advances, and as Courtney Speed would put it, their stories got to be told.