May 12, 2015--Water, Water

Rona was watering the plants on the terrace. It is a late spring here and she was trying to help the plants catch up with the calendar. Some savvy garden person had recommended a week of Boomerang application. Boomerang being a fertilizer that purports to help plants bounce back from the kind of harsh winter the city had endured.

"Just what they need," Rona said, adding, "A boost. But what the plants really need is just the right amount of water."

"Just like us," I said, "We too need just the right amount of watering. Come to think of it," I thought for the first time, "Why is it that they and we require water to live? To survive? We can do without food for weeks but only a few days without water."

Rona paused in her watering. "I'm embarrassed to admit that I too never thought about that. I mean the specifics. The biology in our case and the botany in theirs." She pointed toward her sage plants.

"I think it's universal," I said. "I mean I think all life on earth--animals, sea creatures, all vegetation--all, everything requires water."

"And maybe oxygen too?"

"Probably. Water after all is largely oxygen. H2O. The O being oxygen."

"Remember the time we were in the Namibian Dessert? You had work to do in Windhoek and I came along so after you were done we could take a week to look around."

"I remember that. Great landscape, great animals, interesting people."

"Unusual for us,"Rona recalled, "we hired a guide to take us into the dessert. It was amazing. Some of the world's biggest sand dunes. And . . ."

"I know where you're going with this," I said. "There were those pants that were millennia old. Thousands of years old. He said, the oldest plants on earth."

"How parched they looked. Actually dead."

"But from his canteen he wet one with maybe two, three drops of water. That was all."

"And with that they sprang back to life."

"As with Boomerang," I winked.

"Exactly. Amazing."

"I need to learn more about water. Probably from Wikipedia."

Which I did and here is some of what I learned--

First, the Namibian plant is Welwitschia, named for the German botanist who classified it, and, yes, some are more than 2,000 years old.

And, also true, all living things, all, require water to live. They, we use water in different ways--humans versus, say, sage plants.

For us water is essential to the proliferation of life. It carries out this role by allowing organic compounds to react in ways that contribute to cellular replication. It is vital as a solvent, dissolving many cell components and the chemicals and compounds cell division requires. In this way water is essential to many, perhaps most of the body's metabolic processes.

In one called catabolism, water is used to break the bonds of large molecules in order to generate smaller ones--glucose, fatty acids, and amino acids--to be used as fuel for biological energy. Without water these metabolic processes could not exist. And neither could we.

For sage plants and other flora water is essential to photosynthesis and respiration. Photosynthetic cells such as chlorophil use the sun's energy to split off water's hydrogen from its oxygen. Hydrogen is then combined with CO_{2, which is absorbed from the air or water, to form glucose and release oxygen. All living plant cells use these fuels and in this cycle oxidize the hydrogen and carbon to capture the sun's energy and, through cellular respiration, re-form water and} CO_2.  

"Come on out and take a look at the akebia," Rona called downstairs to me, luring me away from the computer. "It's about to bloom and the flowers have such a lovely scent."

"Your garden is amazing," I said. "As Wiki says . . ."

She cut me off. "Forget Wiki. Sit by the honeysuckle," She whispered. "I saw a humming bird. Rare for the city. But they love the nectar of honeysuckle."

"Sit very still," Rona suggested. I did and sure enough, after a half hour . . .

Welwitschia Plant