DNA Transcription and Translation

Which of the following post-transcriptional modifications does not directly contribute to increasing mRNA stability?

In prokaryotic cells, the lack of a nuclear envelope allows for the spatial separation of transcription and translation, leading to a more regulated gene expression environment compared to eukaryotes.

Describe how alternative splicing can lead to proteomic diversity, and provide an example of a specific protein family where alternative splicing plays a crucial role.

The phenomenon where multiple codons can encode the same amino acid is known as codon __________, providing a buffer against mutations in the third nucleotide position.

Match each regulatory mechanism with its primary mode of action in controlling gene expression:

Which of the following events would likely lead to the least amount of change in the resulting protein sequence?

During translation, the Shine-Dalgarno sequence in eukaryotes facilitates the direct binding of tRNA to the mRNA, initiating protein synthesis.

Explain the role of chaperones in post-translational modification and how they influence protein folding and function.

__________ is a post-translational modification involving the addition of a ubiquitin molecule to a protein, often signaling it for degradation by the proteasome.

Match each type of RNA with its specific function in protein synthesis:

Which of the following regulatory elements is most directly involved in initiating transcription in eukaryotes?

In eukaryotes, transcription factors only function to increase the rate of transcription, and there are no factors that can actively repress gene expression.

Describe the process of RNA editing and its potential impact on the protein product.

The process of __________ allows a single gene to code for multiple proteins by including different combinations of exons in the final mRNA product.

Match each post-translational modification with its typical effect on protein function:

Which of the following steps in gene expression is not a common target for regulatory control?

The genetic code is universal, meaning that all organisms use the exact same codons to specify the same amino acids.

Explain how microRNAs (miRNAs) regulate gene expression, including the mechanisms by which they interact with mRNA molecules.

__________ are DNA sequences that enhance transcription by binding transcription factors and can be located far upstream or downstream from the gene they regulate.

Match each type of post-transcriptional modification with its primary function:

During translation, what role does the release factor play?

In eukaryotic cells, all mRNA molecules have the same lifespan, ensuring uniform levels of gene expression.

Describe how phosphorylation can affect protein function and provide examples of cellular processes regulated by protein phosphorylation.

The __________ complex is responsible for removing introns from pre-mRNA in eukaryotic cells.

Match each component of the ribosome with its primary function:

Which of the following is not a function of the 5' cap on eukaryotic mRNA?

Prokaryotic mRNAs typically contain introns that must be removed by splicing before translation can occur.

Explain the significance of the Kozak sequence in eukaryotic translation initiation.

__________ are proteins that bind to specific DNA sequences to either enhance or repress transcription of a gene.

Match each post-translational modification with the amino acid residue it typically modifies:

Which of the following mechanisms does not directly regulate the amount of protein produced from a given mRNA molecule?

The wobble hypothesis explains how a single tRNA molecule can recognize multiple codons that differ only in their first nucleotide.

Describe the role of the proteasome in regulating protein levels within the cell.

__________ are non-coding RNA molecules that regulate gene expression by binding to mRNA and either promoting its degradation or blocking translation.

Match each component with its function in eukaryotic transcription:

Which of the following post-translational modifications is most likely to target a protein for degradation?

The rate of transcription is constant for all genes within a cell, ensuring equal expression levels.

Explain the role of the signal recognition particle (SRP) in protein targeting.