Central Dogma of Biology
Sequential information is transferred (or transcribed) residue by residue from DNA to RNA in every cell’s nucleus. The corresponding RNA is then modified to varying degrees, and transported out of the nucleus into the cytoplasm, where the genetic sequence is translated (via ribosomes) to make proteins.
DNA and RNA are nucleic acids, or long polymers made of of singular units calls nucleotides. A unit of three sequential nucleotides in a messenger RNA molecule is called a codon, and each codon codes for a single amino acid in the protein. Proteins are often made up of thousands or hundreds of thousands of amino acids.
The central dogma also states that the process cannot operate in reverse; proteins cannot be used to create RNA or DNA.
The central dogma is the single most important aspect of molecular biology.
In his 1988 autobiography, What Mad Pursuit, Francis Crick wrote about his choice of the word “dogma” and some of the problems it caused him:
I called this idea the “central dogma,” for two reasons, I suspect. I had already used the obvious word “hypothesis” in the sequence hypothesis, and in addition I wanted to suggest that this new assumption was more central and more powerful. … As it turned out, the use of the word dogma caused almost more trouble than it was worth…. Many years later Jacques Monod pointed out to me that I did not appear to understand the correct use of the word dogma, which is a belief that cannot be doubted. I did apprehend this in a vague sort of way but since I thought that all religious beliefs were without foundation, I used the word the way I myself thought about it, not as most of the world does, and simply applied it to a grand hypothesis that, however plausible, had little direct experimental support.