Question

What are the two alleles for flower color in Snapdragon?

Answer 1

Hint: The process in which two true-breeding parents are crossed and give off an intermediate offspring, also known as heterozygous, is called incomplete dominance. It is also known as partial dominance or intermediate inheritance. In incomplete dominance, the variants or alleles are not expressed as dominant or recessive; rather, the dominant allele is expressed in a reduced ratio.

Complete answer:
Genes are the most initial and functional unit of heredity. It means that genes form our DNA structure and are responsible for all the genetic characters that we have. In humans, one from each parent, everyone has two copies of each gene, known as an allele. These alleles of a gene are responsible for the variations and distinctiveness of each individual. These different variations of a particular gene are known as an allele.
Antirrhinum majus is the generic name for the Snapdragon flower. The Snapdragon flower is also called the dragon flower because of its similar appearance to the face of a dragon.
 In incomplete dominance, both of the alleles in a heterozygous condition incompletely express themselves. In this, the dominant allele cannot completely hide the effect of the recessive allele.
So, if a Cross pollination occurs between a red snapdragon and white snapdragon flower, it will result in a pink snapdragon flower. This shows that neither the white allele or red allele is dominant.
The pink color results from the mixing of both the two alleles that are white allele and red allele. The dominant red allele is represented by RR and rr represents the recessive white allele. In F1 generation, Rr will be the genotype of pink colored progeny of parent snapdragon. In F2 generation, when two heterozygotes are crossed, it will result in 1 red colored snapdragon, 2 pink colored snapdragon and 1 white colored snapdragon, in the ratio 1:2:1.

Note:
Codominance is a type of inheritance in which the alleles of a gene pair in a heterozygote are completely expressed. As a consequence, the phenotype or physical characters of the offspring are a combination of the phenotype of the parents. Thus, the trait is neither dominant nor recessive. Codominance in humans is represented by individuals with type AB blood group. A person inheriting the alleles IA and IB will have a type AB blood because IA and IB are codominant and therefore will be expressed together.