1–20 of 22
Recent research has shown that exhaust from lungs (part of excretion) is a major factor in weight loss. Burning 10 kg human fat requires inhalation of 29 kg oxygen. This produces 28 kg carbon dioxide and 11 kg water. As food and drinks are temporarily stored in the human stomach and bowels, the body weight is…
The next hundred years will be a period of transition between the metal-and-silicon technology of today and the enzyme-and-nerve technology of tomorrow. The enzyme-and-nerve technology will be the result of combining the tools of genetic engineering and artificial intelligence. We cannot hope to predict the concrete…
The very first time you learned about carbon dioxide was probably in grade school: We breathe in oxygen and breathe out carbon dioxide. Any eight-year-old can rattle off this fact. More specifically, the mitochondria within our cells perform cellular respiration: they burn carbohydrates (in the example shown below…
As we look at planet Earth and the factors that enabled us to be here, we quickly realize that our planet is very special. Here’s a short list: the long-term existence of a protective and oxygen-rich atmosphere; Earth’s axial tilt, stabilized by a single large moon; the ozone layer and the magnetic field, which…
Every vitamin is made by living cells — either our own, or in other species. Vitamin D is produced in our skin, for example, when sunlight strikes a precursor of cholesterol. A lemon tree makes vitamin C out of glucose. Making a vitamin is often an enormously baroque process. In some species, it takes 22 different…
The account of the origin of life that I shall give is necessarily speculative; by definition, nobody was around to see what happened. There are a number of rival theories, but they all have certain features in common. The simplified account I shall give is probably not too far from the truth. We do not know what…
The humanist ethic begins with the belief that humans are an essential part of nature. Through human minds the biosphere has acquired the capacity to steer its own evolution, and now we are in charge. Humans have the right and the duty to reconstruct nature so that humans and biosphere can both survive and prosper…
One of the main causes of warming is the increase of carbon dioxide in the atmosphere resulting from our burning of fossil fuels such as oil and coal and natural gas. To understand the movement of carbon through the atmosphere and biosphere, we need to measure a lot of numbers. I do not want to confuse you with a lot…
Here's a simple question: Why do you weigh more when you go to sleep than when you wake up? Because you do... You can check this yourself. Somehow, while doing absolutely nothing all night but sleep, you will wake up lighter. [...] All night long, every time you breathe out, a bunch of carbon atoms, formerly inside…
The atoms like each other to different degrees. Oxygen, for instance in the air, would like to be next to carbon, and if they get near to each other, they snap together. If they’re not too close though, they repel and they go apart, so they don’t know that they could snap together. It’s just as if you had a ball, it…
Many species of terrestrial plants, including the skunk cabbage that sprouts in February in the woods of Princeton, New Jersey, where I live, are warm-blooded to a limited extent. For about two weeks the skunk cabbage maintains a warm temperature by rapidly metabolizing starch stored inside the part of its anatomy…
Our understanding that increasing carbon dioxide levels in the atmosphere could change the climate is not new. The relationship between carbon dioxide, water vapor, and climate was first laid out in detail in 1896 by the Swedish physicist Svante Arrhenius, who estimated that a doubling of carbon dioxide levels would…
In every economic transaction there is a willing buyer and a willing seller. and they agree on a price that benefits both. But there are spillover effects in many economic transactions—costs and/or benefits that are transferred to third parties. Friedman called these spillovers "neighborhood effects." Today, most…
It is the destiny of wine to be drunk, and it is the destiny of glucose to be oxidized. But it was not oxidized immediately: its drinker kept it in his liver for more than a week, well curled up and tranquil, as a reserve aliment for a sudden effort; an effort that he was forced to make the following Sunday, pursuing…
In the Ne± Netherlands, a unique partnership between Shell Oil Company and Dutch greenhouse businesses enables surplus carbon dioxide produced at the Shell refinery in Pernis, outside Rotterdam, to be pumped into greenhouses as an alternative to pumping it directly into the atmosphere as waste. The partnership was…
Once upon a time, about ten or fifteen billion years ago, the universe was without form. There were no galaxies. There were no stars. There were no planets. And there was no life. Darkness was upon the face of the deep. The universe was hydrogen and helium. The explosion of the Big Bang had passed, and the fires of…
Though one might imagine "living" organisms such as intelligent computers produced from other elements, such as silicon, it is doubtful that life could have spontaneously evolved in the absence of carbon. The reasons for that are technical but have to do with the unique manner in which carbon bonds with other…
when they are more used to sleeping alone, sleep differently when with when they are more used to sleeping alone, sleep differently when with their mothers. The babies seem to spend a greater percentage of their sleep time in levels 1-2 and less time at the deeper levels, exhibit more REM sleep, and are awake longer…
No law of physics is more basic than the law of entropy, the tendency of the universe to move toward disorder and death. But life bucks the tide. using available free energy wherever it can get it, and hereabouts the most abundant source of energy is sunlight. The mayflower constructs its tiny oasis of order by…
When the first single-celled organisms appeared on Earth, more than 3 billion years ago, they fed upon carbohydrates—sugars—dissolved in the sea. The sugars had their origin in chance chemical reactions. Life, however, multiplied exponentially; one cell made two, two made four, four made eight, and so on. Self…