That genome tells cells when to grow and divide and makes sure they do their jobs, whether that's controlling your heartbeat or helping your brain understand the words on this page.Īll it takes is one small mistake anywhere in the division process for cells to start growing out of control, he told us. The nucleus is the brains of the operation inside every nucleus within each cell in your body, there's an identical copy of your entire genome. All the while, little cytoplasmic factories work 24/7, cranking out sugars, fats, proteins, and energy to keep the whole thing running and feed the nucleus.
It's crammed full of molecules and vessels endlessly shuttling enzymes and sugars from one part of the cell to another, pumping water, nutrients, and oxygen in and out of the cell. The cytoplasm buzzes like a New York City street. Under the microscope, a cell looks a lot like a fried egg: It has a white (the cytoplasm) that's full of water and proteins to keep it fed, and a yolk (the nucleus) that holds all the genetic information that makes you you. They make up all our tissues-muscle, bone, blood-which in turn make up our organs. What he wanted us to understand was that cells are amazing things: There are about one hundred trillion of them in our bodies, each so small that several thousand could fit on the period at the end of this sentence. Yes, Defler said, we had to memorize the diagrams, and yes, they'd be on the test, but that didn't matter right then. "Do we have to memorize everything on those diagrams?" one student yelled.
I'd transferred to an alternative school that offered dream studies instead of biology, so I was taking Defler's class for high-school credit, which meant that I was sitting in a college lecture hall at sixteen with words like mitosis and kinase inhibitors flying around. I was a kid who'd failed freshman year at the regular public high school because she never showed up. They were schematics of the cell reproduction cycle, but to me they just looked like a neon-colored mess of arrows, squares, and circles with words I didn't understand, like "MPF Triggering a Chain Reaction of Protein Activations." He pointed to two diagrams that appeared on the wall behind him. My instructor, Donald Defler, a gnomish balding man, paced at the front of the lecture hall and flipped on an overhead projector. I first learned about HeLa cells and the woman behind them in 1988, thirty-seven years after her death, when I was sixteen and sitting in a community college biology class. I'm pretty sure that she-like most of us-would be shocked to hear that there are trillions more of her cells growing in laboratories now than there ever were in her body. I've tried to imagine how she'd feel knowing that her cells went up in the first space missions to see what would happen to human cells in zero gravity, or that they helped with some of the most important advances in medicine: the polio vaccine, chemotherapy, cloning, gene mapping, in vitro fertilization. I've spent years staring at that photo, wondering what kind of life she led, what happened to her children, and what she'd think about cells from her cervix living on forever-bought, sold, packaged, and shipped by the trillions to laboratories around the world. She's simply called HeLa, the code name given to the world's first immortal human cells- her cells, cut from her cervix just months before she died. She's usually identified as Helen Lane, but often she has no name at all. No one knows who took that picture, but it's appeared hundreds of times in magazines and science textbooks, on blogs and laboratory walls. Beneath the photo, a caption says her name is "Henrietta Lacks, Helen Lane or Helen Larson." Her light brown skin is smooth, her eyes still young and playful, oblivious to the tumor growing inside her-a tumor that would leave her five children motherless and change the future of medicine. It's the late 1940s and she hasn't yet reached the age of thirty. She looks straight into the camera and smiles, hands on hips, dress suit neatly pressed, lips painted deep red.
There's a photo on my wall of a woman I've never met, its left corner torn and patched together with tape.
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