22. What is probably the single most important distinction between bacteria and eukaryotes?
a. transcription
b. the separation of the cell's genetic material from the surrounding cytoplasm
c. the existence of ribosomes
d. RNA processing in bacteria
e. antibiotics
23. Which one does NOT characterize an open reading frame (ORF)
a. Uses six reading frames during translation
b. Contains a start codon
c. Contains a stop codon
d. Its length is in multiples of 3 nucleotides
e. It should have the number of codons for a protein or on average ~250 codons in length.
24. Nested intronic genes lie within the non-coding intronic region of a larger gene, and occur in the human genome.
a. True
b. False
25. How would you characterize this statement: EF-Tu will hydrolyze GTP only if the codon:anticodon & tRNA:amino acid matchings are correct
a. Transcription; initiation steps
b. Transcription; termination steps
c. Translation: initiation steps
d. Tanslation: elongation steps
e. Spliceosome
26. Regarding the transcription unit architecture of the Escherichia coli genome, which one is FALSE?
a. Each of the 4,661 transcription units comprised an average of 1.1 modular units.
b. 3,010 transcription units (~65%) are monocistronic.
c. 1,652 transcription units (35%) contain more than one ORF (polycistronic)
d. The largest transcription unit is equivalent to 16 ORFs with numerous introns.
e. 398 transcription units (~9%) are nested within each other in opposite transcriptional orientation
27. Regarding RNA interference (RNAi), which one is FALSE?
a. It is a common and conserved mechanism in eukaryotic cells.
b. Originally discovered in bacteria and plant viruses.
c. A form of primitive immunity to protect the genome.
d. Pre microRNA (miRNA) genes have been found in introns.
e. Recent research shows that exogenous plant miRNAs in food can regulate the expression of target genes in mammals.
28. Aminoacyl-tRNA synthetases
a. Recognize the 3âUTR
b. The genes for these enzymes fall into the family of inducible genes
c. The enzymes are imported into the nucleus
d. Covalently attaches an amino acid to the appropriate tRNA. This takes place in the cytoplasm.
e. Forms the peptide bond during protein synthesis
29. What is the process by which complementary RNAs are made from a DNA template?
a. translation
b. transcription
c. protein synthesis
d. transduction
e. transliteration
