3. Complete dominance: Inheritance of black and red colour in cattle

10. Inheritance of ABO blood group in human P generation Female x Male Phenotype blood group A blood group B Genotype I A /I A I B /I B Gametes All I A All I B F 1 Genotypes All I A /I B F 1 Phenotypes All blood group AB Interbreeding F1 F 1 generation Female x Male F 1 Phenotype blood group AB blood group AB F 1 Genotype I A /I B I A /I B F 1 Gametes ½ I A , ½ I B ½ I A , ½ I B F 2 genotypes ¼ I A /I A , ½ I A /I B ¼ I B /I B F 2 Phenotypes ¼ blood group A ½ blood group AB ¼ blood group B F 2 Phenotypic ratio 1:2:1 for blood group A: blood group AB : blood group B

18. Agouti (banded) hair Agouti Non-agouti Eumelanin Phaeomelanin

25. The inheritance of X-linked genes: red eyes and white eyes in Drosophila melanogaster P generation parent 1 x parent 2 Parental phenotype Female, red - eyes Male, white eyes Parental genotype X w+ X w+ X w Y Gametes all X w+ ½ X w , ½ Y F 1 generation F 1 genotype ½ X w+ X w , ½ X w+ Y F 1 phenotype ½ female, red eyes ½ male, red eyes Interbreeding F 1 generation parent 1 x parent 2 F 1 phenotype Female, red eyes Male, red eyes F 1 genotype X w+ X w X w+ Y F 1 Gametes ½ X w+ , ½ X w ½ X w+ , ½ Y

29. (i) Genotypes A and B rank differently in the two environments

30. (ii) Genotypes A and B rank the same in the two environments i.e B is the best in both environment, but the advantage of B is much less in environment 2