Question

When a snapdragon plant bearing pink colour flower was selfed, it was found that, 69 plants were having red coloured flowers. What would be the number of plants bearing pink flower and white flower. Show with the help of Punnett square. Identity the principle of inheritance involved in this experimen?


class 12thCBSE Biology sample paper

Answer 1

In a snapdragon plant the phenotype ratio is 1:2:1. if 69 plants having red coloured flowers then the number of pink flowers will be 138 and the number of white flowers will be 69.

Answer 2

 a) If the pink coloured snapdragon flower is selfied and produce 69 red colouerd flowers then ,There will be 138 pink flower bearning plants and 69 white flower bearing plants.

 b)           gamete             R                      r

                  R                  RR                   Rr

                  r                    Rr                    rr

      

  Phenotypic ratio -  red : pink : white        ===       1  :   2    :  1

 c)The principle of inheritance involved in this type of experiment is

         Incomplete dominance