Question

The central dogma of protein synthesis is
(a) DNA-DNA- mRNA-protein
(b) mRNA-gRNA-DNA-protein
(c) gDNA-DNA-mRNA-protein
(d) DNA-gRNA-mRNA- protein

Answer 1

Hint: Central dogma is the concept that gene expression involves an intrinsic unidirectional information flow from the information storage system to the final gene product through an intermediate message carrier system. According to it, a direct flow of information straight from DNA to protein or a reverse flow from protein to DNA is not possible

Complete answer:
Central dogma essentially explains the functional interrelation between DNA, mRNA, and protein, which is its cardinal aspect. DNA serves as a template for its own replication, and also for transcription of mRNA. gRNA or guide RNA directs the insertion or deletion uridine residues into the mitochondrial mRNA. This mRNA in turn undergoes translation and forms protein. Thus according to central dogma, DNA does not directly govern or undertake protein synthesis, but it makes mRNA, and mRNA makes protein. So there is no direct flow of information from DNA to protein. The information in DNA is first copied to make mRNA, which serves as a template molecule and guides the synthesis of a specific protein.
-Transcription involves the copying of genetic information on DNA to mRNA
-Genetic translation is the transfer of biological information from mRNA to protein in the form of an amino acid sequence.
-Translation of mRNA to protein is irreversible.

So, the correct answer is 'DNA-gRNA-mRNA-Protein'.

Note:
-Replication, Transcription, and Translation are the three main processes used by all cells.
These are used to maintain their genetic information and to convert the genetic information encoded in DNA into gene products, which are either RNAs or proteins, depending on the gene.
-The central dogma of molecular biology states that DNA contains instructions for making a protein, which is copied by RNA. RNA then uses the instructions to make a protein.