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How Life Is

Many of the properties of living beings, like breathing, growing and reproduction can also be appreciated in the inert world.
On occasions, biologists aren't capable of separating the living from what isn't.

There is a property, the most elemental, that a blue whale and the smallest bacteria have in common. It is a faculty unfortunately imprecise, very hard to state explicitly, even though every mortal thinks that he can distinguish between a living being and a piece of inert matter.


The most elemental structure of any living being, either an enormous whale or bacteria, is a cell.

But it isn't as simple as it sounds. Even though scientists have been able to learn about the most intimate components of life, manipulate genetic material, and investigate about life on other planets, scientists have to recognize that sometimes they find themselves with serious difficulties to assure with certainty that what they have before them is living matter. This situation is due to the fact that there isn't a definition that in one part explains the properties of everything that can be considered living and also satisfies all biologists.

Nevertheless, life can sort of be considered as a mechanism that exists naturally. It isn't difficult to guess that the goal of something living is to survive, compete and reproduce it's species. But some of these characteristics that we consider particular to living beings are also present in the inanimate world. A car, for example, can eat, breathe oxygen, metabolize the fuel and excrete oil and water as it moves. ¿Wouldn't a car be more alive than anaerobic bacteria, that doesn't breathe oxygen, or a tardigrate, a minute animal capable of remaining dehydrated and latent for decades? Another example: a virus is incapable of reproducing itself on it's own without the intervention of a cell that it can occupy as a parasite, meanwhile a crystal grows and makes copies of itself with enormous ease. Many robots also have apparently more vitality than many of these microorganisms. But, which one is alive?

What is life? A set of peculiar molecules? A metabolism or transformation of matter?
A medium of energy? It's evolution and selection of information?

Maybe the solution to the puzzle can be found in the answer to this and other subjects that since Aristotle, who considered that living matter was characterized by being capable of feeding itself and decomposing, have been emerging and delimiting the world of the living. So with this idea in mind, let's proceed to the determine:

The Cocktail of Life

1997 Eduardo Diaz Diaz

Last updated: April 24th, 1997