The fascinating world dell'ultrapiccolo avvicnata me to the study of genetics, to understand what we are made and where we're going ... The
DNA, as almost everyone knows, consists of two polynucleotide chains that wrap around each other in right-handed helix, according to Mondello, a spiral staircase of Watson and Crick (although there are other possible conformations).
The diameter is 2 nm, the two chains are antiparallel, ie, two filaments are oriented in opposite directions.
DNA is a macromolecule, ie with a molecular weight of several thousand daltons (one dalton is 1 / 12 the mass of the atom carbon 12), consisting of a polymer of nucleotides in which each nucletide comprises:
1. pentose (5 carbon atoms in sugarmill: deoxyribose)
2. A nitrogenous base adenine, G guanine, T thymine, cytosine, and C): AT and GC pairs as nitrogen bases form the rungs of the 'ladder' DNA.
3. a phosphate group. Some
sequence of DNA bases code for amino acids and therefore proteins that are essential because they give functionality to the cell type or organism, 20 amino acids form the proteins present in us all ...
DNA can be genetic mutations (changes in structure incorrect) due to:
- spontaneous changes
- errors in the replication
- engaging in particular chemicals or radiation ....
mutations are important elements of the evolutionary process, a mutation can be passed on to daughter cells and seguienti generations giving rise to mutated cells or mutant individuals.
It 'important to note, and do not know why this thing has caught my attention, that X-rays and ultraviolet rays can penetrate the tissues and collide with atoms of the individual in question, giving rise to ions and free radicals that can break the chemical bonds of DNA damage by creating different mutations including .... our sun è una fonte molto forte di radiazioni UV e qui vorrei lasciare libero il vostro arbitrio di giungere ognuno alle sue conclusioni... Il 90% del DNA non codifica per nessuna proteina, ed è detto per questo DNA spazzatura, sembrava fossero residuati evolutivi inutilizzati, ma dal punto di vista teorico, la presenza di alte proporzioni di DNA spazzatura sembra essere contro la logica evoluzionistica: la replicazione di una tale quantità di informazioni inutili, infatti, sembrerebbe essere un grande spreco di energia. Gli organismi con una minore quantità di junk DNA, risparmiando energia, dovrebbero presentare un vantaggio selettivo e, lungo l'evoluzione, il DNA spazzatura sarebbe dovuto scomparire. In base This, it seems clear that the non-coding DNA must have some function and more than a relic of the information could be something not yet activated ...
these sequences could be a sort of reserve when uncoded , but from which would emerge some gene that confer advantage to the organism. From this point of view, therefore, these regions constitute the true genetic basis of evolution. 
few days ago it was discovered their important function in regulating gene expression and therefore what we are .... and here I leave you free in your own conclusions .... 
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