ANSWERS TO CHAPTER SEVEN 1. Answer: a. The nucleoside takes on a phosphate group in order to become a nucleotide. 2. Answer: d. In the DNA molecule, there is hydrogen bonding. The adenine molecule forms a hydrogen bond with thymine in all cases. 3. Answer: a. The histone proteins are the smallest, followed by the nucleosome, solenoid, and chromosome, in order of larger size. 4. Answer: d. A nucleosome consists of an octet of histone proteins that have DNA wrapped around them. 5. Answer: a. In the mRNA molecule, the introns are spliced out and the exons remain as part of the complete, finished molecule. It gets a cap and a tail as well. 6. Answer: c. The transcript is made from messenger RNA and is the strand that is made during the transcription process. 7. Answer: c. Ribosomal RNA gets made and assembled in the nucleolus, where it later goes to the ribosomes in order to participate in the translation process. 8. Answer: d. tRNA or transfer RNA has a covalent linkage to an amino acid so that it can transfer the amino acid to a peptide chain in the making of proteins. 9. Answer: a. The DNA helicase enzyme separates the two DNA strands and unwinds them so that a new strand can be added in the process of DNA replication. 10. Answer: b. DNA ligase is the enzyme that joins the different Okazaki fragments after the DNA is completely replicated on the lagging strand.
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