Question

What is DNA-dependent RNA synthesis?

Answer 1

DNA dependent RNA synthesis is the concept of transcription. From the DNA, RNA is formed, which is made possible by the enzyme RNA polymerase. Thus, transcription is the synthesis of RNA from DNA. Transcription takes place in the cytoplasm of prokaryotic cells and occurs in the nucleus of eukaryotic cells. Genetic information flows from DNA into protein and protein is the substance, which gives an organism its form.

Complete answer:
RNA molecule is a straight, unbranched and thread-like structure. The size and amount of RNA molecules is different from species to species. Depending on the nutritional conditions of a cell, the quantity of RNA varies.
Genetic RNA of viruses is able to perform self-duplication and the mode of replication is RNA dependent RNA synthesis. The non-genetic RNA is not able to perform self-duplication. In this case, the DNA molecule acts as a template for the synthesis of various non-genetic RNA molecules. This kind of synthesis is referred to as DNA dependent RNA synthesis.
RNA polymerase is a multisubunit enzyme, which catalyzes the process of transcription, where RNA polymer is synthesized from a DNA template.
The template DNA strand in the RNA synthesis at the time of transcription is called antisense or anticoding strand, while the other strand is coding or sense strand as the base sequence is the same as the sequence of newly synthesized mRNA. The sequence of RNA polymers is complementary to that of template DNA.

Note:
Flow of information happens because of transcription and translation. DNA polymerase and RNA polymerase differ in their activity though both of them catalyse nucleotide polymerization reactions. RNA polymerase does not require a polymer, but DNA polymerase needs. RNA polymerase is able to start the reaction from the middle of a DNA strand and read “Stop” signals, which cause the enzyme complex to dissociate from the template.