I'm thankful for Carbon

In previous posts (see here for a link to them) I have mentioned various things that I am grateful for. I listed some chemical elements, including Carbon, but I want to devote a whole post to this subject.

Carbon is one of the approximately 100 types of matter -- the elements -- that make up the material world.

Why emphasize Carbon specially? Well, that's a good question. Life as we know of would not be possible without many, maybe even most, of all the elements, not just Carbon. But Carbon is special to life.

Suppose you had to invent life from scratch. You would need building blocks that would be readily available to living things, or life would have been too difficult. You would need building blocks that can be assembled into many complex structures, or the complexity of information that is necessary for life would not have been possible. Consider language and the alphabet -- to have the complexity of language information that we have, we must have the capacity to make complex structures, like words, sentences, and paragraphs, from assemblies of simple structures -- letters. Carbon is the basis of the complex molecules that make life possible. I know, they are also made of other things, such as Hydrogen, Oxygen, Nitrogen, Sulfur, and other chemical elements, but Carbon is the key. Why is that? It is because Carbon has two properties. One of these is that Carbon is readily available to living things. Carbon's atoms are light, compared to, say, those of Iron. Carbon Dioxide, therefore, is a light substance, which is gaseous under common conditions, thus readily available to the green plants that turn it into food in photosynthesis. If Carbon were heavier, this could not happen.

The other property is that Carbon, with its six electrons, will readily form covalent bonds with four other atoms, including other atoms of Carbon, all at the same time. Huh? What does that mean? Consider our hands. Most of us have two. We could hold hands with two other people at the same time (or with one person, holding both hands). This makes it theoretically possible to make straight chains of people holding hands. Such chains could be very long, but they wouldn't be especially complex. They would be one-dimensional. Now, suppose we had four hands. We could make two-dimensional structures (or three-dimensional, if some of us would stand on ladders or get down in holes) much more complicated than straight chains of people. We could make complicated structures, indeed, in this way. If molecules could only be long, straight, chains, the complexity of the molecules we depend on, such as proteins and DNA, would be impossible. Both proteins and DNA have many Carbon atoms which are attached to three or four other atoms, making molecules with complex three-dimensional structures possible. The basic building blocks of proteins are amino acids. The heart of each amino acid is a Carbon atom, which is attached to four different groups of atoms at the same time.

I have inherited characteristics from my ancestors. I have had the privilege of passing on some of these characteristics to my daughters and my grandson. The information that makes this possible is carried in DNA molecules. The complexity of DNA makes this possible. DNA, too, has many Carbon atoms that are attached to four different groups of atoms at the same time.

It isn't just DNA and proteins. All the basic foods -- the substances we take in to give us energy -- are based on Carbon. Their smells and tastes are largely because of the Carbon-based molecules in their substance. So is their color. There are also human-made molecules that we have come to depend on, such as plastics, and man made fibers. Fuels are possible because of Carbon-based molecules. So are wood, paper, and many other things. We are, truly, Carbon-based life forms.

So, in this Thanksgiving season, I'm thankful to God for Carbon. Without it, I wouldn't be here, and you wouldn't be, either. I also thank Rebecca for suggesting that November be a month of blogger gratitude emphasis. I have also used this emphasis as an excuse to be thankful for the electromagnetic spectrum, and for cell division.

Thank you for reading.