Biology is about big and small. Really big (a whale) and really, really small (a bacterial cell). For a beautiful visual tour of the big to the very small, I can recommend this from the Learn Genetics website (this website was recently awarded the Science prize for online resources in education). This animated web page lets you zoom from a coffee bean down to a virus and a protein. To get with the jargon its an “order-of-magnitude” thing. Like all jargon, this is a fancy way of saying something simple. Two numbers differ by an order of magnitude if one is ten times bigger or smaller than the other – its just the number of zeros before or after the “1”. For example, 1 meter is 2 orders of magnitude larger than 1 cm (1 m = 100 cm). A blue whale is about 30 m long. A bacterial cell has a diameter of about 1 micrometer! All in all, life on our planet covers 7 orders of magnitude – a blue whale is 7 orders of magnitude bigger than a bacterium (30 m = 30,000,000 micrometers)!
For big and small biological numbers, many orders of magnitude apart (and for the geeks amongst us), there are a plethora of interesting and wacky examples at B1ONUMBERS. There are icky numbers – there are 10 times as many bacterial cells in your body compared to your own cells. There are practical numbers – ordinary “white collar” work requires about 8,000,000 Joules of energy per day (about 1,910,000 calories). There are environmental numbers – the average turnover of plant organic matter on land is 19 years. There are amazing numbers: An E. coli bacterium must consume 2,000,000,000 molecules of glucose before it can divide in two! For the skeptics, B1ONUMBERS provides you with the original reference and you can find out exactly how the scientists arrived at that particular value. And for the rigorous, the authors at B1ONUMBERS have written great paper on “A feeling for numbers in biology“.
In an earlier post, I talked about the ribosome which is the molecular machine that translates the information on DNA and RNA to manufacture proteins in our bodies. How fast can it do this? B1ONUMBERS says… ~16 amino acids per second! How often does the ribosome make a mistake? About once every 5 thousand amino acids!