Question

Which event contradicts the central dogma of molecular biology?

A) DNA replication
B) RNA transcription
C) Protein synthesis
D) Reverse transcription

Answer 1

Reverse transcription, facilitated by the enzyme reverse transcriptase, contradicts the central dogma by converting RNA back to DNA, which is the reverse of the normal flow of genetic information.

Step-by-step explanation:

Reverse transcription contradicts the central dogma of molecular biology, which states that the flow of informational sequences is from DNA to RNA to protein. However, reverse transcription, utilized by certain viruses like HIV, converts RNA back to DNA, thus violating the central dogma.

During the process of reverse transcription, the enzyme reverse transcriptase transcribes RNA into DNA, which can then integrate into the host genome and be used for protein synthesis. This step is in opposition to the conventional flow described in the central dogma where information is never supposed to go from RNA to DNA.

Answer 2

Reverse transcription contradicts the central dogma of molecular biology by reversing the flow of genetic information, synthesizing DNA from an RNA template using the enzyme reverse transcriptase.

Step-by-step explanation:

The event that contradicts the central dogma of molecular biology is reverse transcription. The central dogma of molecular biology, a framework for understanding the flow of genetic information, states that DNA is transcribed into RNA, which is then translated into protein.

This sequence is conventionally represented as DNA to RNA to protein. Reverse transcription, which is the process of synthesizing DNA from an RNA template, is a reversal of this flow and is not accounted for by the original central dogma.

The enzyme reverse transcriptase, which is carried by certain viruses such as HIV, performs this process. It transcribes RNA into DNA, which is the opposite of the usual process and thus contradicts the central dogma.