A molecule of DNAIdentification by the DNA, GMO, cloning, antenatal diagnoses, the genetics is everywhere, becoming a science with whole share. How do our genes determine our characteristics ? How are our cells recopied ? From which do the genetic changes come ? Why are we all different ? How is held the evolution of the species ? These questions directly concern us, because they are the key of our existence and our life. Here thus some brief replies...
To understand them, you should read those pages in order : Bases of the genetics, The synthesis of proteins, The mitosis, The changes, The genetic mixing.

(image : first drawing of a molecule of DNA, made in 1953 by Francis Crick, who discovered the molecule)