1. Tardigrade
  2. Question
  3. Biology
  4. When two pure pea plants one having round seeds and the other having wrinkled seeds are crossed, their offsprings have:

Q. When two pure pea plants one having round seeds and the other having wrinkled seeds are crossed, their offsprings have:

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Solution:

The gene which controls starch synthesis in pea also controls the shape of the seeds. Thus, it is a pleiotropic gene. The dominant allele B and recessive allele is b.
BB: Round seeds with large starch grain
Bb: Round seeds with intermediate starch grain
bb: wrinkled seeds with small starch grain
Thus, if the shape of seed is considered as the phenotype, alleles show complete dominance, whereas for starch grain, it shows incomplete dominance. In the given example, BB x bb produces Bb which are all heterozygotes having round seeds with intermediate starch grain.