Final answer:
The limitations of using bacteria as hosts for eukaryotic gene expression studies include the inability of bacteria to process eukaryotic mRNA, different transcription and translation mechanisms, and the inability to correctly fold and modify eukaryotic proteins. Thus, the correct answer is '4) All of the above'.
Step-by-step explanation:
The limitations to the use of bacteria as hosts in studies of eukaryotic gene expression include a few different factors. One major limitation is that bacteria lack the necessary cellular machinery to process eukaryotic mRNA which includes capping, polyadenylation, and splicing. This leads to issues as eukaryotic transcripts require extensive processing before translation, which bacteria cannot perform.
Another limitation is that bacteria have fundamentally different transcription and translation mechanisms compared to eukaryotes. For example, bacteria use a single type of RNA polymerase to transcribe all kinds of RNAs, whereas eukaryotic cells use different RNA polymerases for synthesizing rRNA, tRNA, and mRNA.
Moreover, bacteria may not be able to correctly fold and modify eukaryotic proteins. Eukaryotic proteins often require post-translational modifications such as glycosylation, phosphorylation, and correct folding, which are typically not performed by bacterial cells.
Therefore, the correct answer to the student's question is '4) All of the above', indicating that all stated options are limitations when using bacterial hosts to study eukaryotic gene expression.