Question

Gene expression in eukaryotes could be regulated at \[ \begin{aligned} I. &\text{Transcription level} II. &\text{Translation level} III. &\text{Splicing processing level} IV. &\text{mRNA transport level from nucleus to the cytoplasm} \end{aligned} \] (and = all, only = only)

• A. I and II only
• B. II, III and IV only
• C. I, II and IV only
• D. I, II, III and IV

Hint:

Gene expression in eukaryotes is regulated at \[ \boxed{ \begin{aligned} &\text{Transcription} &\text{RNA processing (splicing)} &\text{mRNA transport} &\text{Translation} \end{aligned} } \] Hence, all four levels are involved.

Answer 1

The Correct Option is D

Step 1: Recall the regulation of gene expression in eukaryotes. Gene expression in eukaryotes can be regulated at several stages: \[ \boxed{ \begin{aligned} &\text{Transcriptional level} &\text{Post-transcriptional (RNA processing/splicing) level} &\text{Transport of mRNA from nucleus to cytoplasm} &\text{Translational level} \end{aligned} } \]

Step 2: Examine each statement. \[ \begin{aligned} I. &\text{Transcription level} &&\checkmark II. &\text{Translation level} &&\checkmark III. &\text{Splicing processing level} &&\checkmark IV. &\text{mRNA transport from nucleus to cytoplasm} &&\checkmark \end{aligned} \] Thus, all four statements are correct.

Step 3: Choose the correct option. Hence, the correct option is \[ \boxed{(D).} \]