Question

If hybrid red-flowered plants of pea are crossed back to the pure red-flowered parent, the progeny will show
A. All red-flowered plants
B. White-flowered plants
C. 50% red and 50% white-flowered plants
D. 3 red: 1 white-flowered plants

Answer 1

Hint: This is an example of a monohybrid cross as only a single character is considered in this cross.

Complete answer: The plant is hybrid red – it means the red color is dominant.
When this red hybrid plant is crossed back with a pure red flower, all the progeny will red in color as red is dominant.

So, the correct answer is option A. All red-flowered plants.

Note: It is a back cross because a hybrid red flower is crossed with its dominant parent. From the monohybrid cross, Mendel gave – the Law of segregation.
This law tells about the alleles segregated randomly when gametes are formed, each allele of one parent separates aimlessly into the gametes, so that half of the gametes of a parent can carry each allele.