Central dogma in molecular biology states that genetic information flows from:
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → DNA → mRNA → Protein
Option (1) DNA → DNA → Lipid — Incorrect. DNA does copy itself (replication), but it never codes for lipids. Genes code for RNA and proteins; lipids are made by enzymes, which are proteins.
Option (2) DNA → mRNA → Protein — Correct. The central dogma, proposed by Francis Crick, states that genetic information flows from DNA to mRNA (transcription) and then from mRNA to protein (translation).
Option (3) Protein → mRNA → DNA — Incorrect. This is the reverse of the central dogma. Information does not flow from protein back to RNA or DNA; it flows from DNA to RNA (transcription) and from RNA to protein (translation).
Option (4) DNA → Protein → mRNA — Incorrect. The mRNA comes before the protein, not after it. DNA is first transcribed into mRNA, and the mRNA is then translated into protein.
NCERT Extract:
Structure of Polynucleotide Chain – “… The proposition of a double helix structure for DNA and its simplicity in explaining the genetic implication became revolutionary. Very soon, Francis Crick proposed the Central dogma in molecular biology, which states that the genetic information flows from DNAàRNAàProtein.”