Question

When a true-breeding red flower plant is crossed with a true-breeding white flower plant, the resulting generation shows all pink flower plants. Explain.

Answer 1

Incomplete dominance:

1. True breeding is a type of breeding in which both parents produce offspring with the same phenotype.
2. This tells the parents are homozygous.
3. True breeding occurs in plants when plants self-pollinate.
4. It produces offspring of the same variety.
5. A plant with red flowers will produce seeds with red flowers.
6. The trait is passed down through true-breeding to subsequent generations.
7. In this case, both parents are dominant and recessive.
8. The appearance of the pink flower is not known as blending.
9. It is because different alleles do not combine.
10. They segregate from each other during gamete formation.
11. It results in the pink flower.
12. This is referred to as incomplete dominance.
13. Genotypic ratio = 1: 2: 1 i.e. RR:rr:rr
    
14. The phenotypic ratio = 1: 2: 1 red:pink:white