Chapter 13

13. 1. Leucine, serine, or phenylalanine

    2. Isoleucine, tyrosine, leucine, valine, or cysteine

    3. Phenylalanine, proline, serine, or leucine

    4. Methionine, phenylalanine, valine, arginine, tryptophan, leucine, isoleucine, tyrosine, histidine, glutamine, or a stop codon

15. 1. amino—Met-Thr-Gly-Ser-Gln-Leu-Tyr-Stop—carboxyl

    2. amino—Met-Thr-Gly-Asn-Stop—carboxyl

    3. amino—Met-Thr-Ala-Ile-Asn-Tyr-Ile—carboxyl

    4. amino—Met-Thr-Gly-Asn-His-Leu-Tyr-Stop—carboxyl

    5. amino—Met-Thr-Thr-Gly-Asn-Gln-Leu-Tyr-Stop—carboxyl

    6. amino—Met-Thr-Gly-Asn-Gln-Leu-Tyr-Stop—carboxyl

17. 1. A single base-pair substitution resulting in a missense mutation.

    2. A single-base substitution resulting in a nonsense mutation.

    3. The deletion of a single nucleotide resulting in a frameshift mutation.

    4. A six-base pair deletion has occurred, resulting in the elimination of two amino acids (Arg and Leu) from the protein.

    5. The insertion of three nucleotides resulting in the addition of a Leu codon.

20. 1. 5′–AG–3′	to	5′–AA–3′
       3′–TC–5′		3′–TT–5′

    2. 5′–AG–3′	if A is deaminated, then	5′–GG–3′
       3′–TC–5′		3′–CC–5′
       5′–AG–3′	if C is deaminated, then	5′–AA–3′
       3′–TC–5′		3′–TT–5′

23. The flanking repeat is in boldface type.

    1. 5′—ATTCGAACTGAC [transposable element]

       TGACCGATCA—3′

    2. 5′—ATTCGAA [transposable element]

       CGAACTGACCGATCA—3′

27. The breeder can look for plants that have increased mutation rates in either their germ-line or somatic tissues. If they are defective in DNA repair, they should have higher rates of mutation.