Reference no: EM133436629
Question
1. A particular mutation results in constitutive expression from the trp operon. Which of the following could explain this phenotype?
A. The antiterminator hairpin is unable to form.
B. The terminator hairpin is unable to form.
C. The repressor can no longer bind to tryptophan.
D. The repressor is always bound to the operator.
2. Which of the following is TRUE about HAT (histone acetyltransferase)?
A. HAT removes acetyl groups from histones.
B. HAT adds acetyl groups to DNA.
C. HAT makes chromatin more compact and less available for transcription.
D. HAT activity is usually linked to increased gene expression.
3. Which of the following is an example of a cis acting eukaryotic gene regulatory element?
A. RNA polymerase
B. General transcription factor
C. TATA binding protein
D. Enhancer
4. Which type of DNA sequence would a repressor bind to?
A. Silencer
B. Enhancer
C. Insulator
D. TATA box
5. Which type of reversible post-translational modification can activate or deactivate a protein, depending on which protein is targeted?
A. Phosphorylation
B. Glycosylation
C. Methylation
D. Proteolysis
6. Where does initial glycosylation begin in the cell?
A. Golgi apparatus
B. Endoplasmic reticulum
C. Mitochondrion
D. Nucleus
7. Which post translational modification is not reversible?
A. Proteolysis
B. Phosphorylation
C. Glycosylation
D. Methylation
8. Which of the following is a difference between miRNA and siRNA regulation of gene expression?
A. siRNA is derived from the same genetic locus as the mRNA it regulations, while miRNA comes from another location in the genome,
B. Only siRNA associates with the RISC to induce mRNA destruction.
C. Only miRNA directed activity of the RISC leads to mRNA degradation,
D. Both siRNA and miRNA are evolutionarily conserved across closely related species.
9. Which of the following is a difference between miRNA and siRNA regulation of gene expression?
A. siRNA is derived from the same genetic locus as the mRNA it regulations, while miRNA comes from another location in the genome,
B. Only siRNA associates with the RISC to induce mRNA destruction.
C. Only miRNA directed activity of the RISC leads to mRNA degradation,
D. Both siRNA and miRNA are evolutionarily conserved across closely related species.
10. Which mechanism of alternative splicing can also be a means of gene regulation by resulting in destruction of mRNA before they leave the nucleus?
A. Mutually exclusive exons
B. Alternative promoters
C. Intron retention
D. Alternative polyadenylation sites