Guardian, Georgina Ferry, on September 29, 2007 has reviewed the book: “Eating the Sun: How Plants Power the Planet” by Oliver Morton.
We all are taught photosynthesis is very simple. Carbon dioxide plus water plus energy from the sun equals glucose plus oxygen. It’s not that simple.
Scientists were not satisfied with this cookery-book approach from the earliest years of the 20th century. They finally discovered
“…the number of molecules of the photosynthetic pigment chlorophyll that it takes to produce one molecule of oxygen in full sunlight is not one, but 2,480. Trapping energy, storing and releasing it is all about transferring electrons along chains of molecules,..”
“…To make use of the energy locked up in our food we need oxygen. For more or less the first half of its life, the Earth had very little oxygen in its atmosphere. By around 2.4bn years ago, oxygen produced by photosynthetic bacteria was beginning to build up in the atmosphere in quantities that could support animal life. In an astonishing evolutionary short cut, some of the first multi-celled organisms then engulfed these green bacteria and incorporated their photosynthetic machinery into their own cells. Result: an explosion of green plants that covered the planet in (relatively) short order…”
“Astrobiologists tend to agree that whatever forms life might take, on Earth or elsewhere, it will always need oxygen. The trick, then, is to develop telescopes that can detect oxygen in the atmospheres of planets orbiting other stars. How many of these there might be, in Morton's view, is "the biggest question that we currently have it in our hands to answer".
Therefore, when you next pass by an ordinary weed, you may like it or not, just bow a little.
Artist: James Stevenson The New Yorker May 18, 1963
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