The Song of the Cell: An Exploration of Medicine and the New Human

by Siddhartha Mukherjee

Perhaps, as we near the end of this book, we might pause to reflect on one of the most potent philosophical legacies of twentieth-century science—and its limitations. “Atomism” argues that material, informational, and biological objects are built out of unitary substances. Atoms, bytes, genes, I had written in an earlier book. To this we might add: cells. We are built of unitary blocks—extraordinarily diverse in shape, size, and function, but unitary nonetheless. Why? The answers can only be speculative. Because, in biology, it is easier to evolve complex organisms out of unitary blocks by permuting and combining them into different organ systems, enabling each to have a specialized function while retaining features that are common across all cells (metabolism, waste-disposal, protein synthesis). A heart cell, a neuron, a pancreatic cell, and a kidney cell rely on these commonalties: mitochondria to generate energy, a lipid membrane to define its boundaries, ribosomes to synthesize its proteins, the ER and Golgi to export proteins, membrane-spanning pores to let signals in and out, a nucleus to house its genome. And yet, despite the commonalities, they are functionally diverse. A heart cell uses mitochondrial energy to contract and act as a pump. A beta cell in the pancreas uses that energy to synthesize and export the hormone insulin. A kidney cell uses membrane-spanning channels to regulate salt. A neuron uses a different set of membrane channels to send signals that ena...

Epistemic