Concept explainers
Which of the following best represents the central dogma of gene expression?
- During transcription, DNA codes for polypeptides.
- During transcription, DNA codes for mRNA, which codes for polypeptides during translation.
- During translation, DNA codes for mRNA, which codes for polypeptides during transcription.
- None of the above are correct.
Introduction:
The central dogma is a theory of molecular biology. It describes the process of gene expression in the living organism, which suggests that gene expression takes place in two steps, transcription and translation.
Answer to Problem 1TY
Option (b).
Explanation of Solution
Explanation for correct answer:
Option (b) During transcription, the DNA codes for mRNA and the mRNA codes for polypeptide in translation. According to the central dogma of molecular biology, the flow of genetic information is from DNA(RNA(Polypeptide. The DNA codes for the formation of mRNA in the process called transcription. The mRNA codes for polypeptide in the process is known as translation.
Explanation for the incorrect answer:
Option (a) During translation, DNA codes for the polypeptide. The translation is a process, in which mRNA codes for the polypeptide. Hence, it is an incorrect answer.
Option (c) During translation, DNA codes for mRNA and the mRNA codes for polypeptide during translation. According to central dogma, transcription is the process, in which DNA codes mRNA and translation is the process, in which mRNA codes for the polypeptide. Hence, it is not the correct answer.
Option (d) none of the above are correct. The correct answer is option (b), hence, it is an incorrect option.
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Chapter 10 Solutions
Principles of Biology
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