17 ch homework - Google Docs PDF

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questions and answers to ch 17 homework questions: mastering biology ...

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1. Stop codons are unique because they do not code for amino acids that allow a releasing factor to bind to the A site of the ribosome. 2. Bacteria can transcribe and translate human genes to produce human proteins because the genetic code is nearly universal 3. In eukaryotic cells, a signal peptide by a signal-recognition particle targets a growing peptide to the endoplasmic reticulum 4. Transcription is the synthesis of RNA using information in the DNA 5. Insertions and deletions are called frameshift mutation 6. The function of tRNA during protein synthesis is to deliver amino acids to their proper site during protein synthesis 7. The genetic information of eukaryotic cells is transferred from the nucleus to the cytoplasm in the form of RNA 8. The TATA box is a eukaryotic promoter that allows for the binding of transcription factors and RNA polymerase II. 9. How many nucleotides are needed to code for a protein with 450 amino acids? At least 1,350 10. Which of the following best describes the arrangement of genetic information in a DNA molecule? The three-nucleotide words of a gene are arranged in a nonoverlapping series on the DNA template strand 11. Gene espression is the process by which DNA directs the synthesis of proteins 12. When RNA is being made, the RNA base U always pairs with the base A in DNA 13. Eukaryotic processing of the primary transcript includes the addition of a 5’ cap, a 3’ poly-A tail, and the splicing out of introns 14. The sickle-cell B-globin mutation is an example of a missense mutation 15. The translation is the synthesis of a polypeptide using information in the mRNA 16. What is a key difference in gene expression between eukaryotic and prokaryotic cells? In prokaryotic cells, the mRNA transcript is immediately available as mRNA without processing 17. Because the bacterial cell’s DNA is not surrounded by a nuclear envelope, coupled transcription and translation occur 18. The “triplet code” refers to the fact that three nucleotides code for a single amino acid 19. Who formulated the one gene-one enzyme hypothesis? Beadle and Tatum

20. The type of point mutation that results in a premature stop codon is called a nonsense mutation 21. By bombarding the fungus Neurosporacrassa with x-rays, Beadle and Tatum were able to study nutritional mutants and characterize enzymes in a biochemical pathway 22. The structures called snRNPs are part of a spliceosome 23. Plysomes may be defined as groups of ribosomes 24. RNA molecules that function as enzymes are called ribozymes 25. An exception to the one gene-one enzyme hypothesis is that not all genes code for enzymes some genes code for structural proteins such as keratin 26. Which of the following is a post-translation modification of a polypeptide? Cleavage of a polypeptide into two or more chains 27. Which of the following catalyzes the linkage between ribonucleotides to form RNA during gene expression? RNA polymerase 28. The bonds that hold tRNA molecules in the correct three-dimensional shape are hydrogen bonds 29. In order for transcription to occur in that strand, there would have to be a specific recognition sequence, called a promoter, to the left of the DNA sequence indicated....