Chapter 14, Problem 1TYU

The regulation of most bacterial genes occurs at the level of (a) transcription (b) translation (c) replication (d) posttranslation (e) postreplication

Summary Introduction

Introduction: Genes are sets of nucleotides that codes for a particular protein. The genes have to be expressed for the synthesis of a protein. Gene regulation is a process where the expression of genes is controlled for the synthesis of specified gene products (usually RNA or proteins). This gene expression is regulated depending on the requirement of the cell. For example, cell division proteins are synthesized prior to the cell division. Prokaryotic and eukaryotic genes have differential gene expression in order to suit the specific needs of the cell.

Answer to Problem 1TYU

Correct answer: The regulation of most bacterial genes occurs at the level of transcription.

Hence, the correct answer is option (a).

Explanation of Solution

Reason for the correct answer:

Bacterial cells are prokaryotic cells and are unicellular. Therefore, they have limited components for all its essential functions. Another reason is that they have a very short life cycle, so fewer components are synthesized. Gene expression in bacteria occurs only when the environmental conditions are favorable such as the availability of food. In prokaryotic gene regulation, the half-life of mRNA is very less in order not to accumulate many mRNA and prevent unnecessary protein synthesis. In order to produce RNA and proteins at the time of requirement only and prevent unnecessary accumulation of molecules, bacteria have transcriptional-level control as part of gene regulation. Transcriptional-level control is found to be very efficient in bacteria as it helps to regulate the genes based on requirement, and favorable environmental conditions.

Option (a) is given as “transcription”.

Bacteria have transcriptional-level control as part of gene regulation.

Hence, the correct answer is option (a).

Reasons for incorrect answers:

Option (b) is given as, “translation”.

Translation is the process of formation of the protein inside the ribosomes. The bacterial genes regulate at the transcriptional-level, not at translational-level.

Hence, option (b) is incorrect.

Option (c) is given as, “replication”.

DNA replication is the process of the synthesis of the double strand by the action of the enzyme $\text{DNA}$ polymerase. The bacterial genes regulate at the transcriptional-level, not during replication.

Hence, option (c) is incorrect.

Option (d) is given as, “posttranslation”.

The bacterial genes regulate at the transcriptional-level, not at posttranslational level.

Hence, option (d) is incorrect.

Option (e) is given as, “postreplication”.

The bacterial genes regulate at the transcriptional-level, not at postreplication level.

Hence, option (e) is incorrect.

Hence, the options (b), (c), (d), and (e) are incorrect.

Conclusion

Transcription is the process of the formation of the $\text{mRNA}$ template from the $\text{DNA}$ template. The bacterial genes regulate at the transcriptional-level.