Tell us how DNA synthesis works.
The DNA molecule is completely untwisted – despiralized, the hydrogen bonds connecting the complementary linked polynucleotide chains are broken and each of them becomes a matrix for the synthesis of new chains.
A whole group of enzymes takes part in the process of DNA synthesis. One of the most important is DNA polymerase. DNA doubling occurs according to the principle of complementarity and is carried out with very high accuracy – new molecules are absolutely identical to the old one, and each of them consists of one old and the second newly synthesized polynucleotide chains. Without this, the preservation and transmission of genetic information by inheritance, which ensures the development of traits inherent in the body, would be impossible. Changes in the structure of the DNA molecule that occur under the influence of external factors are eliminated with the help of special enzymes. Thus, the constancy of hereditary information is ensured by matrix DNA synthesis and the restoration of damaged parts of the molecule through enzymes. As a result of DNA doubling during mitotic cycle processes, each chromosome contains twice as many DNA molecules as it did, but the number of chromosomes does not change. The cell formula becomes 2p4s.
