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The calcitonin gene can encode either the hormone calcitonin or a protein called calcitonin-gene-related peptide depending on which 3′ cleavage site is used. In the thyroid gland, cleavage and polyadenylation occur after the fourth exon leading to calcitonin production. However, in the brain, the exact same transcript is cleaved after the sixth exon yielding calcitonin-gene-related peptide. This is possible because of a process known as:

Scientists have developed novel techniques that allow them to visualize the process of DNA replication in vitro. What conclusions can you draw about the DNA replication process shown below?

In the procedure above, they mentioned that the purified protein was alkylated. Briefly explain why it might be desirable to treat the reduced protein with iodoacetic acid (ICH2CO2H) before it is subjected to further purification by HPLC. 

Upload an image of your answers to this question. If you decided to use a PIPES buffer (piperazine-N,N’-bis(2-ethanesulfonic acid)) instead of the HEPES buffer used in this procedure, how many moles of the protonated form of PIPES and how many moles of deprotonated form of PIPES would you have to add to 1.0 liter of water to prepare a 0.10 M PIPES buffer at pH 7.5? The appropriate pKa is 6.76.  Show your work for full or partial credit. (Note: The sulfonic acid portion of the molecule is a strong acid and hence, fully deprotonated at pH 7.5.)

The partial sequence a prokaryotic operon regulatory region is shown below. What are the names and approximate locations of the consensus sequences that are crucial for binding of the transcription machinery? (select all that apply)

Why is the presence of multiple consensus sequences (from the previous question), important for transcription? (Select all that apply)

Which of the following predictions are accurate about your findings?

Which type of chromosome mutations: Decrease the amount of genetic material in a particular chromosome?  [option1] Increase the amount of genetic material in a particular chromosome? [option2] Increase the amount of chromosomes in a cell?  [option3] Change the position of DNA sequences in a single chromosome without changing the amount of genetic material?  [option4]    

A scientists is analyzing the karyotype of a newly discovered organism. This organism diploid and has  2n = 22 chromosomes. How many chromosomes will be found per cell in each of the following mutants in this species? Monosomic   [option1]  Trisomic [option2] Nullisomic [option3]

The agouti locus helps determine coat color in mice, and this phenotype can vary from light to dark between genetically identical individuals. You have discovered a drug that reduces the variation in the agouti phenotype. Which of the following options could explain this drug’s mechanism of action?