In sweat pea, genes C and P are necessary for colours in flowers. The flowers are white in the absence of either or both the genes. What will be the percentage of coloured flowers in the offspring of the cross Ccpp × ccPp?
In sweat pea, genes C and P are necessary for colours in flowers. The flowers are white in the absence of either or both the genes. What will be the percentage of coloured flowers in the offspring of the cross Ccpp × ccPp?
The correct option is B 25%
This is an example of complementary genes. They are non-allelic genes which independently show a similar effect but produce a new trait when present together in the dominant form. In this case, the genes C and P will independently(CCpp and ccPP) produce white coloured flowers but when they come together in dominant condition (CCPP/CcPp), coloured flowers will be produced. The cross will take place as follows:
P: Ccpp x ccpP
Gametes: (Cp, cp) x (cp, cP)
F1: 1/4Ccpp : 1/4CcPp : 1/4 ccpp : 1/4 ccPp
(1/4 colored : 3/4 white)
Thus, 25% will be coloured.
25%
This is an example of complementary genes. They are non-allelic genes which independently show a similar effect but produce a new trait when present together in the dominant form. In this case, the genes C and P will independently(CCpp and ccPP) produce white coloured flowers but when they come together in dominant condition (CCPP/CcPp), coloured flowers will be produced. The cross will take place as follows:
P: Ccpp x ccpP
Gametes: (Cp, cp) x (cp, cP)
F1: 1/4Ccpp : 1/4CcPp : 1/4 ccpp : 1/4 ccPp
(1/4 colored : 3/4 white)
Thus, 25% will be coloured.
