Q.The figure given below shows the concept of the central dogma. Select the correct option for the parts marked 'X', 'Y' and 'Z' in it.

The central dogma of molecular biology gives the flow of genetic information as DNA → mRNA → Protein.

Francis Crick's central dogma describes the normal, one-way flow of genetic information: DNA is transcribed into RNA, and RNA is translated into protein.

The central dogma explains how genetic information stored in DNA is expressed as functional protein. DNA acts as the template for making RNA (transcription); this RNA (mRNA) then carries the genetic message to ribosomes, where it is translated into a specific sequence of amino acids to build a protein (translation). It is a unidirectional flow: DNA -> RNA -> Protein, information does not normally flow back from protein to nucleic acid. (A notable exception exists in retroviruses, where reverse transcri …

The central dogma states that genetic information normally flows in one direction: DNA makes RNA, and RNA makes protein.

Proposed by Francis Crick, the Central Dogma of molecular biology describes the general pathway of flow of genetic information in a cell:

DNA → RNA → Protein

• Transcription: DNA is used as a template to synthesise messenger RNA (mRNA).
• Translation: The mRNA sequence is used to synthesise a specific protein at the ribosome. …

In the Central Dogma, DNA is copied into mRNA by Transcription, and mRNA is decoded into protein by Translation — the given diagram has these two labels interchanged, so correcting it means swapping 'Translation' and 'Transcription' on the two arrows.

The Central Dogma of molecular biology, proposed by Francis Crick, describes the normal, one-way flow of genetic information in a cell: DNA replicates itself, and DNA is expressed via RNA into Protein.

• Replication: DNA makes an identical copy of itself (the self-loop on DNA in the figure) — this part of the diagram is correct.
• Transcription: the process by which a DNA strand is used as a template to synthesise a complementary single-stranded mRNA molecule. So the arrow from DNA to mRNA must be labelled Transcription, not 'Translation' as printed. …

The central dogma of molecular biology: DNA replicates itself, is transcribed (a) into mRNA, and the mRNA is translated (b) into protein.

The central dogma

The diagram represents the central dogma of molecular biology, which describes the normal flow of genetic information in a cell:

• DNA undergoes self-replication (the looping arrow on DNA), making copies of itself that are passed on during cell division.
• DNA also directs the synthesis of messenger RNA (mRNA) using one of its strands as a template — this process, labelled (a), is transcription. …

The printed diagram wrongly labels DNA→mRNA as 'translation' and mRNA→Protein as 'transcription'; the correct labels are the reverse.

The Central Dogma of molecular biology, first stated by Francis Crick, describes the normal one-way flow of genetic information in a cell:

DNA (replicates itself, shown by the looping arrow) → transcription → mRNA → translation → Protein

• Transcription is the process of copying genetic information from one strand of DNA into a complementary sequence of mRNA — this must be the DNA-to-mRNA step.
• Translation is the process of decoding the mRNA's codon sequence into a corresponding sequence of amino acids to build a polypeptide/protein — this must be the mRNA-to-Protein step. …