The Cell
The machinery every living thing shares: membranes and transport, metabolism, the flow from DNA to protein, and how a cell divides.
What a cell is
Why life comes in packages, how the claim that it always does was established, and the physics that decides how big one package can be.
The membrane
A boundary two molecules thick that builds itself from water's dislike of oil, and is so good at its job that almost nothing a cell needs can get through it.
Crossing the membrane
Channels, carriers and pumps, the sodium potassium ATPase and what it costs, and the voltage that appears across a membrane as soon as ions are unevenly distributed.
The price of everything
What decides whether a reaction goes, why the ATP bond is not special, and how a molecule worth about 50 kJ/mol pays for everything a cell does.
Glycolysis and fermentation
Ten steps that every domain of life still runs, how they extract ATP from sugar without any oxygen, and the accounting that shows how little of the fuel they actually use.
Breathing with a gradient
How a cell recovers the ninety-six per cent of a sugar that glycolysis left behind, by spending electrons on a proton gradient and selling the gradient back as ATP.
What the gene is made of
Four experiments between 1928 and 1953 that moved inheritance from protein to DNA and ended with a structure whose shape predicts how it is copied.
Copying it
The experiment that showed each new double helix keeps one old strand, the awkward chemistry that carries the copying out, and the three filters that get the error rate down to one in a billion.
Reading it out
Why the cell copies its genes into a disposable second molecule before using them, how the copy is made and where it starts, and the 1977 discovery that genes come in pieces.
The code and the ribosome
How the dictionary between four bases and twenty amino acids was worked out, why its redundancy is arranged the way it is, and what kind of machine reads it.
Choosing what to make
Why a cell cannot afford to express every gene it has, the bacterial switch that showed how choosing works, and how the same logic scaled up turns one genome into two hundred kinds of cell.
Where a protein goes
How a newly made protein reaches the right compartment, folds without aggregating, and gets destroyed on schedule, and why two of the compartments carry their own genomes.
Shape and movement
The three filament systems that give a cell its shape, why two of them burn nucleotide simply to stay unstable, and the motors that walk along them eight nanometres at a time.
One cell into two
The clock that drives division, the three checkpoints that supervise it, the mechanics of pulling two metres of DNA apart, and what happens when the supervision fails.
The whole subject