The light wave which we rode almost a hundred million miles from the sun has ended its journey by colliding with a tiny molecule inside the cell of the grass, called chlorophyll, where its energy will be harnessed for the plant to use. Light itself is a form of electromagnetic energy, and some organisms are capable of converting that energy into chemical energy which they can use. The chlorophyll molecule itself is embedded in a membrane surrounding a fluid-filled space known as the stroma, somewhat like the skin of a balloon surrounding its air-filled interior. All around us light waves are crashing into the chlorophyll molecules, and the energy carried by these molecules is causing things to happen: molecules are changing shape, being broken, being built, and many tiny hydrogen protons are being moved across the membrane from the outside to the inside.Go to A Life of Life and read from the beginning. Just read a post a day. There aren't too many and the entries are short. We begin by hurtling with a sunbeam (an electromagnetic light wave) from the sun and slamming into the dim, watery world of a grass cell. I cannot tell you how much I have been enjoying these brief but illuminating posts.
Tuesday, March 16, 2010
A Biology Blog for the Non-Specialist: A Life of Life
Finally, an explanation of photosynthesis that makes sense. Perhaps because it is done a bit at a time, very carefully. Here is the piece that began to break it open for me.