CBSE Class 10 Answered

Dominant trait: The trait which can express its effect over contrasting trait is called a dominant trait. It is expressed even in the presence of one copy of an allele for a particular character in the gene, i.e., it is expressed in the heterozygous condition.

Example: Yy represents dominant trait for yellow seed colour. Seed is yellow even when single copy is dominant allele Y is present.

Recessive trait: The trait which cannot express its effect over contrasting trait or which gets suppressed by the contrasting trait is called a recessive trait. It is expressed only when two copies of an allele for a particular character in the gene are present, i.e., it is expressed in the homozygous condition and in the absence of corresponding dominant trait.

Example: yy shows recessive trait for green seed colour. It is expressed only when two copies of recessive allele yy is present.