1.18: A) Met-Ser-Thr-Ala-Val-Leu-Glu-Asn-Pro-Gly. B) This mutation alters the start codon into a non-start codon. Thus, translation will not start with the first AUG; translation would start with the next AUG down the mRNA, or not at all if it is too far down the molecule. C) Met-Ser-Thr-Ala-Val-Leu-Glu-Asn-Pro-Gly (no change). D) The Val is changed into an Ala. E) Met-Ser-Thr-Ala-Val-Leu.
1.19: There are 64 possible codons and only 20 amino acids; hence, many amino acids are specified by two or more codons. A mutation that changes a codon for a particular amino acid into a synonymous codon for the same amino acid does not change the amino acid sequence.
1.20: a) Y, Z and W missing, X in excess; b) Z and W missing, Y in excess; c) W missing, Z in excess
6.1: Each fragment terminates with a single-stranded overhang whose base sequence is complementary to that of any other fragment produced by the same restriction enzyme.
6.10: The DNA in this species is replicated by a totally conservative mechanism, where the parental strands stay together and the daughter strands stay together.
1.5 kb 0.5 kb 0.8 kb 0.3kb