Page 28

155)

In corn, three dominant genes are necessary for aleurone colour. The genotype B_D_R_ is coloured. Any homozygous recessive for one gene is colourless. Predict the genotypes and phenotypes of the offspring of the cross BbDdRR Ă— BbDdrr Answer:

Phenotype: 9 colour; 7 colourless

Ratio of Genotypes 1 BBDDRr 2 BBDdRr 2 BbDDRr 4 BbDdRr 1 BBddRr 2 BbddRr 1 bbDDRr 2 bbDdRr 1 bbddRr 156)

In rats, the gene for the pigment (P) is dominant to no pigment (p). The gene for black (B) is dominant to the gene for cream (b). If a pigment gene (P) is absent, genes B and b are inoperative. Predict the genotypes and phenotypes of the F1 of a cross between a homozygous black rat and an albino homozygous for cream. Answer:

Genotype PpBb

Phenotype Black

27

Profile for mansour.m83m

Test Bank for Genetics 2nd Hartwell  

Test Bank Genetics 2nd Edition Hartwell 2017 (Test Bank Download) (9781259370885) (1259370887). Instant access. All chapter are included. Al...

Test Bank for Genetics 2nd Hartwell  

Test Bank Genetics 2nd Edition Hartwell 2017 (Test Bank Download) (9781259370885) (1259370887). Instant access. All chapter are included. Al...