Calcium. Not just for milk! What started as a post about the mechanisms of calcium signalling in plants fell completely when I realized how complex it was to read about in a week. There is still some cool stuff about calcium and how it makes the world around us work.
Sydney Ringer has one of best science discovery stories. He was keeping rat hearts in tap water suspensions. That is something out of Frankenstein. He found that the hearts would keep contracting in the tap water solutions, but would slow and stop when in distilled water. After some experimentation with calcium salts, he got it to work again. Man, the best that will happen in my job is mold taking over someone's brain.
It helps with nutrient exchange in plants. It signals mychorrzial fungus for penetration of roots epidermal cells. Build up of calcium cations happens when the plant is stressed due to factors such as drought and aboitic stress.
This doesn't answer my question of why it works though. It's frustrating to think that you've come so far in your understanding of things and then you hit something that's above what you actually know. Damnit. And now for me to plug the fact that I want to read Einstein! Because that bastard said lots of things I don't understand.