Question

The textbook presents a very simple, linear scheme of the central dogma of molecular biology (text page 500), but is explicit in noting the simplicity of the original concept and exceptions to it. Which of the following would NOT be reasonable additions or modifications that could be made to this simple linear scheme to account for experimental data?

The textbook presents a very simple, linear scheme of the central dogma of molecular biology (text page 500), but is explicit in noting the simplicity of the original concept and exceptions to it. Which of the following would NOT be reasonable additions or modifications that could be made to this simple linear scheme to account for experimental data?

The arrow between DNA and RNA could be reversible.

The word "protein" should be made plural (i.e., "proteins").

The scheme could be made circular by adding an arrow connecting "protein" to "DNA replication."

RNA can be used to generate RNA-based enzymes (ribozymes), so "protein" at the end of the scheme should be changed to "protein/RNA." The answer is not b

Answer 1

Central dogma of molecular biology is describes as below.

"DNA ---> RNA ---> Protein"

Coming to the questions as mentioned above:

Arrow betwen DNA and RNA cannot be reversible as practically it doesnt happen. When RNA polymerase enzyme binds to the DNA strand, mRNA is made and whether this protein is beneficial or not mRNA cannot go back to DNA. If its not beneficial it would be degraded by nucleases. So the answer is NO IT CANNOT BE REVERSIBLE.

Name protein should be made plural to protein(s):

At a time, DNA is transcribed to mRNA and one mRNA would be translated to single protein. If we need to have more than one protein, these would be coming from different mRNAs. So in explaining different mRNAs.

At the end of scheme, there woudl be saying to protein/RNA. But the defnition of central dogma of molecular biology ends at protein. This would nto be circular process as different genes would be transcribed and translated to different proteins.