![Enterobacter W1 [CC-BY-SA-3.0 Steve Cook]; cylindrical cells about a micron long](https://www.polypompholyx.com/wp-content/uploads/2012/10/Enterobacter-300x297.jpg)
Someone recently asked me, “How many cells are there in the human body?” I have quite a lot of correspondence of this kind, just to be clear. I have to confess my first thought was “Not a bloody clue”. My second thought was “I bet the Internet knows”; but my third was “The Internet is full of …