Law of Segregation Or Law of Purity of gametes with example and mechanism of segregation

Law of Segregation Or Law of Purity of gametes :- Given by Mendel→ 

"When a pair of Constrasting characters remained together in F1 hybrid then both of them live together without Contaminating or blending or intermingling with each ather and get Segregated Completely and in pure form during the formation of gametes"

Example and mechanism of segregation-

• when homozygous red flowered plants are crossed with homozygous white flowered plant than parent plant always produce only one type of gammat as they are homozygous genotype that is red flowered plant and white flowered plant produce gametes 'R' and 'r' respectively.

• The gametes of both the plant, after cross pollination, produce F1 hybrid whose genotype is 'Rr' and phenotype is Red.

• Both the genes (R and r) of red and white colour respectively present together in F1 hybrid, but only red colour is expressed because the gene 'R' of red colour is dominant over the gene 'r' of white colour.

• Both the genes (R and r) live together for a long time in F1 hybrid but they do not affect each other. They neither mix together nor contaminate each other.

• During the gamete formation of F1 hybrid, two types of gametes will form in equal number. Half of the gametes will contain gene 'R' sand the other half will contain the gene 'r' .

• During self pollination this gametes  unite together in three possible combinations- 'RR', 'Rr' and 'rr' and two types of phenotypic plants will produce in F2 generation in which 75% are red flower plants and 25% are white flower plants .

• The appearance of white colour in F2 generation shows that gene 'r' of white colour lives together with the gene 'R' of red colour in F1 hybrid but 'r' gene neither mixes with it nor contaminate by it and gets separated from it during the gamete formation.

This law given by Mendel is called "Law of segregation" or "Law of purity of gametes".