(Зx+2y — 4) х (x-y+2)
Answers
(a) Heterozygous: The condition in which a pair of homologous chromosomes carries dissimilar alleles for a particular character.
For example –
A daughter (XXo) from a normal homozygous mother for colour vision (XX) and a colour blind father has one normal and one defective allele (XoY).
Certain tongue rollers are heterozygous with Rr genotype.
(b) Homozygous: The condition in which a pair of homologous chromosomes carries similar alleles for a particular character.
For example –
A colorblind daughter (XoXo) will have both the X chromosomes with defective alleles.
A non-roller will have rr (homozygous) genotype.
(c) Pedigree Chart: A pedigree chart is a diagram that shows the occurrence and appearance or phenotypes of a particular gene or organism and its ancestors from one generation to the next. In the pedigree chart, males are shown by squares and females by circles.