NOTE: the Provided Figures May Be Useful and Beneficial

NOTE: the Provided Figures May Be Useful and Beneficial

If there are “CUES” listed within the question, please USE them and UNDERLINE them in your answer!

Chapter 17

  1. The template strand of a gene contains the sequence 3’-TTCAGTCGT-5’. Draw the non-template sequence & the mRNA sequence indicating the 5’ & 3’ ends of each. Please state the similarities & differences you notice? (CUES: nucleotides, complementary, antiparallel, uracil, ribose, deoxyribose)
  2. Imagine that the non-template sequence in question 1 was transcribed instead of the template sequence. Draw the mRNA sequence and translate it using Figure 17.5. (Be sure to pay attention to the 5’ & 3’ ends.)
  3. What enables RNA polymerase to start transcribing a gene at the right place on the DNA of a bacterial cell? In a eukaryotic cell? (CUES: promoter,TATA box, transcription unit, transcription factors, upstream)
  4. How can human cells make 75,000 – 100,000 different proteins, given that there are about 20,000 human genes? (CUES: intron, exon, spliceosome, alternative mRNA splicing)
  5. A dog was taken to a veterinary clinic because it had become increasingly inactive and lethargic. A blood test determined that the dog had very low levels of the steroid hormones produced by the adrenal glands, especially cortisol. The veterinarian told the owner that the dog has “a mutation in its cortisol gene.” Explain why this characterization is inaccurate, given that steroid hormones such as cortisol are lipids. Speculate on a way that a genetic mutation could result in low levels of steroid hormones. (CUES: proteins, transcription, translation, smooth ER, ribosome)
  6. Explain why the human gene for insulin can be inserted into an E. coli bacterium and the bacterium can then produce human insulin. (CUES: enzymes, genetic code, ribosomes, evolution, universal)
  7. What happens when one base pair is lost from the middle of the coding sequence of a gene?(CUES: frameshift, amino acids, protein, mutation)
  8. How & where are proteins modified & targeted to different places in the cell?(CUES: SRP, endomembrane system – be specific about which parts)
  9. Use Figure 17.26 to summarize transcription & translation. Include all the events shown. (CUES: codon, anticodon, mRNA, tRNA, 5’, 3’, peptide bond, polypeptide, transcription, intron, exon, nucleus, ribosome, amino acid)

Chapter 19

  1. What 2 properties, one structural and one functional, distinguish heterochromatin from euchromatin? (CUE: transcription)
  2. Use Figure 19.3 to describe the 8 methods of regulation of gene expression. Please include regulation at the DNA, RNA & protein levels.
  3. Use Figure 19.6 to describe how activators binding to an enhancer can stimulate gene transcription. (CUES: activators, silencers)
  4. Human insulin has 52 amino acids and yet it is a product of the INS gene, which has nearly 40,000 base pairs. How many base pairs are required to make 52 amino acids? Why is there a need for these extra base pairs within the INS gene? (CUES: coding region, promoter, UTR, termination sequence, regulation)
  5. If the mRNA being degraded in Figure 19.9 coded for a protein that promotes cell division in a multicellular organism, describe what would happen if a mutation disabled the gene encoding the miRNA that triggers this degradation. (CUES: transcription, translation, cell cycle, cancer)
  6. Explain how the types of mutations that lead to cancer are different for a proto-oncogene and a tumor-suppressor gene, in terms of the effect of the mutation on the activity of the gene product. (CUES: stimulation, inhibition)
  7. Draw the DNA segment at the top of Figure 19.5 on page 365 & assign EACHof the colored DNA segments to its correct sector of the pie chart in Figure 19.14.
  8. What are 3 ways that transposable elements are thought to contribute to a genome’s evolution?
  9. In 2005, Icelandic scientists reported finding a large chromosomal inversion present in 20% of northern Europeans, and they noted that Icelandic women with this inversion had significantly more children than women without it. What would you expect to happen to the frequency of this inversion in the Icelandic population in future generations? Why?

Can Credit Question

Answer the following questions using the links below:

Recent research suggests that a diet rich in certain foods can influence expression of certain genes.

1)Genes involved in what 4 common diseases were activated by a diet rich in carbohydrates?

2)What differences are observed when the C. elegans roundworm is fed a diet of Comamonas bacteria vs. a diet of E. coli bacteria? How many individual changes of gene expression were found in worms eating these two different diets?