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
- Many aspects of gene function can be nicely explained with the one- gene-one-enzyme hypothesis, which states that a gene controls the production of an enzyme. Which of the following findings about gene expression, though, requires an expansion of this simple concept? Non-enzyme proteins are made from genes too. Some genes code for RNA molecules only. Enzymes composed of different polypeptides are coded for by more than one gene. a and c, but not b a, b, and carrow_forwardUnlike in prokaryotic cells, transcription and translation in eukaryotic cells... Group of answer choices are separated: transcription occurs in the cytoplasm, and translation occurs in the nucleus. occur together in the cytosol. occur together in the nucleus. are separated, except for proteins that bind to the DNA and ribosomes, which are translated in the nucleus. are separated: transcription occurs in the nucleus, and translation occurs in the cytoplasm.arrow_forwardWhich of the following statament is NOT TRUE about gene expression? Lüffen birini seçin: O a. Gene expression is the process by which DNA directs the synthesis of proteins O b. During gene expression, the information encoded in genes is used to make specific polypeptide chains or RNA molecules. O c. The expression of genes that code for proteins includes two stages: replication and translation O d. Translation is the synthesis of a polypeptide using the information in the MRNA.arrow_forward
- Many aspects of gene function can be nicely explained with the one-gene-one-enzyme hypothesis, which states that a gene controls the production of an enzyme. Which of the following findings about gene expression, though, requires an expansion of this simple concept? Choose an answer below: Non-enzyme proteins are made from genes too. Some genes code for RNA molecules only. Enzymes composed of different polypeptides are coded for by more than one gene. a and c, but not b a, b, and carrow_forwardAt which of these levels isregulation of gene expression most energy-efficient?arrow_forwardWhich of the following is TRUE about eukaryotic gene expression? The same regulatory proteins are present in every cell of the body. Every cell in the body expresses different genes. Every cell in the body expresses the same genes. The same regulatory sequences are present in every cell of the body.arrow_forward
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