NEET BIOLOGY

Detailed explanation-1: -Diploid organisms that are homozygous for a gene have two identical alleles, one on each of their homologous chromosomes. The genotype is often written as YY or yy, for which each letter represents one of the two alleles in the genotype. The dominant allele is capitalized and the recessive allele is lower case.

Detailed explanation-2: -One member of each homologous pair of chromosomes in inherited from each parent. Both alleles for a trait are the same in an individual. They can be homozygous dominant (YY), or homozygous recessive (yy).

Detailed explanation-3: -The correct answer: The genotype which shows the character of homozygous dominant is D. SS.

Detailed explanation-4: -An organism with two dominant alleles for a trait is said to have a homozygous dominant genotype. Using the eye color example, this genotype is written BB. An organism with one dominant allele and one recessive allele is said to have a heterozygous genotype. In our example, this genotype is written Bb.

Detailed explanation-5: -When the gametes join in the zygotes of the F1 generation, each individual receives one dominant allele and one recessive allele (Yy), and thus all of the F1 generation shows the dominant phenotype (e.g. yellow peas).