Becker's World of the Cell 9th Edition by Lewis Kleinsmith, Jeff Hardin, Gregory Paul Bertoni

Exercise 1

The Genetic Code and Two Human Hormones. The following is the actual sequence of a small stretch of human DNA:

(a)What are the two possible RNA molecules that could be transcribed from this DNA
(b)Only one of these two RNA molecules can actually be translated. Explain why.
(c)The RNA molecule that can be translated is the mRNA for the hormone vasopressin. What is the apparent amino acid sequence for vasopressin (The genetic code is given in Figure 21-6.)
(d)In its active form, vasopressin is a nonapeptide (that is, it has nine amino acids)with cysteine at the N-terminus. How can you explain this in light of your answer to part c
(e)A related hormone, oxytocin, has the following amino acid sequence:

Where and how would you change the DNA that codes for vasopressin so that it would code for oxytocin instead Does your answer suggest a possible evolutionary relationship between the genes for vasopressin and oxytocin