can anyone help me with the final questions?

Question

1. In four-o’clock flowers red petals are incompletely dominant over white petals, producing pink petal flowers in the heterozygous stage. What would be the probability of having white offspring if two pink flowered plants were crossed?

2. In humans, there are three alleles for blood types, A = IA, B = IB, and O = i. Type A and B are co-dominant alleles and type O is recessive. Could a man with type AB blood be the father of a child with type O blood if the mother was heterozygous for type A blood?

Answer 1

1.  Genotype of red flowers is RR, white flowers is WW and pink flowers is RW. When two incomplete-dominant heterozygous plants are crossed, the genotypic (RR:RW:WW) and phenotypic (Red:Pink:White) ratio of the progeny will be 1:2:1.  Probability of white flowers progeny is 1/4 or 0.25.

 

Heterozygous plants produce R and W gametes.  Try to  make a Punnett square with each parent's gametes to find the possible genotypes and phenotypes of the offspring.

 

 

2.  No, blood type AB father can never have  a child with type O blood type.

Genotype of type AB blood is I^AI^B, type O blood is ii.  Type AB does not have the i allele and type O blood needs two i alleles one from each parent.