NEET BIOLOGY

Detailed explanation-1: -Recessive alleles are only expressed when no dominant allele is present. In most sexually reproducing organisms, each individual has two alleles for each gene (one from each parent). This pair of alleles is called a genotype and determines the organism’s appearance, or phenotype.

Detailed explanation-2: -Codominance occurs when the alleles do not show any dominant and recessive allele relationship. However, each allele from homozygote is able to add phenotypic expressions in the offspring or simply the “mix” of each allele. The offspring’s phenotype is an intermediate of the parents’ homozygous traits.

Detailed explanation-3: -Recessive alleles only show their effect if the individual has two copies of the allele (also known as being homozygous?). For example, the allele for blue eyes is recessive, therefore to have blue eyes you need to have two copies of the ‘blue eye’ allele.

Detailed explanation-4: -Co-dominant genes Not all genes are either dominant or recessive. Sometimes, each allele in the gene pair carries equal weight and will show up as a combined physical characteristic. For example, with blood groups, the A allele is as ‘strong’ as the B allele. The A and B alleles are said to be co-dominant.

Detailed explanation-5: -In codominance, both alleles are completely expressed. If you crossed a red flower with a white one and the alleles were codominant, you might get flowers that are red and white in patches. If the alleles were incompletely dominant, the flowers would be pink because the traits blend.