164

In this sense, cells are constantly storing and developing (from each generation to the

next, after the selection of harmful mutations) new information that is essential for sur­

vival in dialogue with the environment.

Each word of this “language of life” only makes sense in the narrow context of the

limited vocabulary of the respective cell. But what is newly learned or spoken is always

determined by the success of adaptation to the environment. On higher levels, this leads to

ever better coordinated processes of homeostasis, i.e. ever stronger abilities to keep cell

conditions optimal in relation to the environment. By the way, it is possible to check for

each real protein or nucleotide sequence whether it is really under a selection pres­

sure or not.

Again, it is with the selection pressure on the individual words so similar to our consid­

erations on evolution. Each word is more or less strongly neutral, i.e. variants are tolerated

or strongly persecuted – how strongly this is the case is decided by the context of the cel­

lular processes.

12.2

Printing Errors Are Constantly Selected Away in the Cell

The information in cells must be maintained and preserved. If biochemical reactions, oxi­

dation, destruction by free radicals, etc. destroy individual proteins, these can be rebuilt on

the basis of the building instructions in the cell nucleus. But if the building instructions

change or are destroyed, the defect can no longer be repaired. And if the resulting error is

bad enough, the cell perishes.

That the printing error leads to something new, positive, on the other hand, is much

rarer (positive mutation).

12.6

­

2011

­

2011

­

­

12.6

12.7

12.7

12  Life Continuously Acquires New Information in Dialogue with the Environment