Answer Key for Chapter 2 Biology Today by Minkoff and Baker, 2/e

1. The genotype of all gametes is: T

2. Pollen from homozygous tall plant: T
Eggs from homozygous short plant: t
Genotype of F1 offspring: Tt
Phenotype of F1 offspring: tall
Pollen from homozygous short plant: t
Eggs from homozygous tallt plant: T
No change in the outcome by simply reversing the genotypes of the male and female parent plants.

3. Eggs from homozygous tall plant: T
Pollen from heterozygous tall plant: T or t
Genotypes of F1 offspring: TT or Tt
Phenotype of F1 offspring: tall

4. Eggs from homozygous short plant: t
Pollen from heterozygous tall plant: T or t
Genotypes of F1 offspring: Tt or tt
Phenotype of F1 offspring: tall or short

5. Yes and Yes.

6. Phenotype of F1 offspring: tall with yellow peas (genotype = TtYy).

7. Phenotypes and ratios of F2 offspring: 9 tall/yellow, 3 tall/green, 3 short/yellow, 1 short/green
Genotypes of F2 offspring: (TTYY, TTYy, TtYY, TtYy) tall/yellow, TTyy, Ttyy (tall/green), (ttYY, ttYy) short/yellow, (ttyy) short/green

8. Eggs from plants heterozygous for height and color: TY, Ty, tY, ty
Pollen from plants homozygous short with green peas: ty
Phenotypes and ratios for F2 offspring: 1 tall/yellow, 1 tall/green, 1 short/yellow, 1 short/green
Genotypes for F2 offspring: TtYy, Ttyy, ttYy, ttyy

9. 2N, 2N

10. 2N, 1N or N

11. In anaphase of mitosis the replicated chromosomes separate, therefore one goes to each pole. Two attached chromosomes go to each end in anaphase of meiosis I, since the homologs separate, not the replicated chromosomes.

12. No. Yes.

13. All. All.

14. One or two, depending on whether they are both in one codon, or end up in adjacent codons (the last of three bases in one and the first of three bases in the next).