How is information read from a DNA molecule? Why, as a result of spiraling of chromosomes, it becomes impossible to read genetic information and there is a cessation of RNA synthesis?
Reading information from a DNA molecule and synthesis of an i-RNA molecule (transcription) takes place in the nucleus. Under the action of enzymes, a double helix of DNA is split. According to the principle of complementarity, nucleotides are arranged on the DNA chain. Then the chain polymerizes under the action of RNA polymerase. Next, the transport of i-RNA to the ribosome occurs. After activation, the t-RNA molecule also moves to the ribosome, where it is attached to i-RNA according to the principle of complementarity. The assembly of the protein molecule (translation).
Chromosomes spiral in the process of cell division, and during this time, plastic metabolism is suspended. Due to spiralization, access to DNA nucleotides becomes impossible, and this is necessary in order to synthesize the corresponding RNA nucleotide by the principle of complementarity. The RNA molecule is linear, and a non-helical segment of one of the DNA strands is required for assembly.
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