0 7. In eukaryotes, why are introns removed before mRNA leaves the nucleus? a) they prevent the binding of mRNA to ribosomes b) they do not code for protein c) the mRNA would be too long to pass through the nuclear pores if the introns remained in it d) they do not consist of the same bases as the rest of the MRNA 8. What is the function of the polyadenine tail that is added to mRNA in eukaryotic cells? a) prevent degradation of the mRNA b) initiate the binding of the mRNA to the ribosome c) help the mRNA to bind to a pore in the nuclear membrane d) act as a signal for the termination of translation 9. Which of the following does RNA polymerase participate in? a) anneling of RNA primers to DNA b) ligation of Okazaki fragments c) removal of introns from mRNA d) transcription e) translation 10. DNA acts as a template for transcription. Which of the following statements regarding the DNA of a gene being expressed is true? a) after unwinding, both of the DNA strands act as templates b) after unwinding, only one of the DNA strands acts as a template c) one strand acts as a template in a continuous manner, while the other strand acts as a template in shorter segments d) the strand with the higher cytosine-guanine content acts as the template 11. Which of the following correctly describes the order in which cell components become involved in protein synthesis? a) DNA polymerase, mRNA, tRNA, ribosome b) mRNA, RNA polymerase, ribosome, tRNA c) RNA polymerase, mRNA, ribosome, tRNA d) DNA, rRNA, tRNA, mRNA 12. Why is the splicing of the first-formed mRNA transcript by spliceosomes necessary? a) the poly-A tail must be removed b) introns need to be added c) the CAP protein must be removed d) the transcript must be freed from the DNA e) introns need to be removed 13. A piece of double-stranded DNA consists of 18 nucleotides. How many codons would the first-formed mRNA transcript have? a) 18 codons b) 9 codons c) 6 codons d) 3 codons