Question

7. Are all prokaryotic genes expressed all of the time? Why or why not? How does the cell know which genes to express and when?

Answer 1

The prokaryotes are single-celled species, which are devoid of a defined nucleus. Thus, their DNA glides freely inside the cell's cytoplasm. To synthesize a protein, the procedures of transcription and translation take place almost side by side. When the ensuing protein is no longer required, the process of transcription ceases. Thus, regulation of transcription is the initial procedure to monitor that what kind of protein and what concentration of protein is articulated in a prokaryoticcell. All of the corresponding steps take place inevitably. When more protein is needed, more amount of transcription takes place. Therefore, in prokaryotes, the monitor of gene expression is mainly done at the level of transcription For example, bacteria possess certain regulatory particles, which monitor that whethera specific gene will be transcribed into mRNA or not. In bacteria, the genes are generally found in operons. These operons permit the cell to effectively articulate the arrangements of genes whose products are required at the similar time. Certain operons are generally off but can be a switch on by a small molecule. This molecule is known as an inducer, and the operon is known as inducible. Other operons are generally on but can be switched off by a small molecule. This molecule is known as a corepressor, and the operon is known to be repressible. The regulation of gene permits the bacteria to react towards the alterations in their surrounding by changing the expression of the gene. Thus, there are various genes that play specialized functions and are articulated only under some circumstances. Though, there are also certain genes whose products are continuously required by the cell to sustain essential functions. These housekeeping genes are continuously articulated underusual conditions of development.