Question

The given flow chart shows the central dogma reverse.
Enzymes used in processes A, b, and C are respectively

I. A- DNA dependent DNA polymerase, B- RNA dependent DNA polymerase, C-DNA dependent RNA polymerase
II. A- DNA dependent DNA polymerase, B- DNA dependent RNA polymerase, C- RNA dependent DNA polymerase
III. A- DNA dependent RNA polymerase, B- DNA dependent DNA polymerase, C-RNA dependent RNA polymerase
IV. A- RNA dependent DNA polymerase, B- DNA dependent RNA polymerase, C-RNA dependent RNA polymerase.

Answer 1

Hint: In molecular biology, central dogma demonstrates the flow of genetic information from DNA to RNA to protein. It is elucidated as a process in which the information in DNA is converted into a functional product. It is suggested that the information present in DNA is very much important or essential to make up all proteins and RNA acts as a messenger that carries information through the ribosomes.

Complete answer: The process of replication/copying of DNA demands the action of a DNA Polymerase enzyme that utilizes a DNA template for the synthesis of another complementary DNA strand synthesis. Thus it is a DNA dependent DNA polymerase.
-The transcription process of the DNA code to make RNA includes another enzyme called RNA polymerase which uses DNA as a template to synthesize RNA and hence is a DNA-dependent RNA polymerase.
-The process of formation of DNA from RNA is very much rare and generally known as reverse transcription and is catalyzed by the enzyme Reverse transcriptase that utilizes RNA as the template to synthesize DNA and hence, it is an RNA dependent DNA polymerase.
Thus, the correct answer 'A - DNA dependent DNA polymerase, B - DNA dependent RNA polymerase, C - RNA dependent DNA polymerase'.
Hence, the correct answer is Option II.

Note: In central dogma, DNA codes for mRNA, which codes for a protein. One very popular exception to the central dogma is exhibited by retroviruses. These RNA-encoded viruses possess a phase in their life cycle in which their genomic RNA is converted back to DNA by an enzyme called reverse transcriptase. This is known to take place in the case of retroviruses, like HIV, as well as in eukaryotes.