Question

1. The splicing of a pre-mRNA transcript is involved in which type of expression control? (one)

-post translational control
-translational control
-post transciptional control
-chromatin structure
-transcriptional control
The rate of degration of mRNA is the cytoplasm is what level of expression control? (one)
-post translational
-chromatin structure
-post transciptional
-this does not alter expression

Answer 1

1. The splicing of a pre-mRNA transcript is involved in post-transcriptional control.

Post-transcriptional control refers to the regulation of gene expression that occurs after transcription, but before the final mRNA product is translated into a protein. Splicing is a key step in post-transcriptional control, where introns (non-coding regions) are removed from the pre-mRNA transcript, and the exons (coding regions) are joined together to form the mature mRNA molecule. This process allows for the production of different mRNA isoforms from a single gene, leading to the synthesis of different proteins with distinct functions.

2. The rate of degradation of mRNA in the cytoplasm is a form of post-transcriptional control.

After transcription, mRNA molecules are exported from the nucleus to the cytoplasm, where they are subject to various mechanisms that control their stability and degradation. The rate of degradation of mRNA molecules in the cytoplasm can affect the overall level of gene expression. If mRNA is rapidly degraded, the amount of protein produced from that mRNA will be lower compared to when mRNA is stable and protected from degradation. This post-transcriptional control mechanism plays a role in regulating gene expression by modulating the lifespan of mRNA molecules in the cytoplasm.

In summary, the splicing of pre-mRNA is a form of post-transcriptional control, while the rate of mRNA degradation in the cytoplasm is another aspect of post-transcriptional control. These processes work together to regulate gene expression and ultimately impact protein synthesis.

Answer 2

Answer: The splicing of a pre-mRNA transcript is involved in post transcriptional control. This process refers to the removal of introns, non-coding regions, and the joining of exons, coding regions, in the pre-mRNA molecule. Splicing ensures that the final mRNA molecule contains only the necessary coding sequences, which can then be translated into proteins.

To understand this better, let's consider an example. Imagine you have a pre-mRNA molecule that contains both coding and non-coding regions. The splicing process would remove the non-coding regions, leaving only the exons. This ensures that when the mRNA molecule is translated, only the relevant coding sequences are used to produce a functional protein.

On the other hand, the rate of degradation of mRNA in the cytoplasm is a form of post-transcriptional control. Once the mRNA molecule is transcribed, it can undergo degradation in the cytoplasm, which affects the overall level of gene expression. If the mRNA is rapidly degraded, the protein encoded by that mRNA will not be produced efficiently, leading to lower levels of gene expression.

To summarize:

- The splicing of a pre-mRNA transcript is involved in post-transcriptional control, as it ensures that only the relevant coding sequences are included in the final mRNA molecule.

- The rate of degradation of mRNA in the cytoplasm is also a form of post-transcriptional control, as it affects the overall level of gene expression by regulating the stability of mRNA molecules.

I hope this helps!