Question

Read the statements given below and choose the correct option.

Assertion (A): In Mirabilis jalapa (4 O’ clock plant), a cross between Red flowered plant and White flowered plant (both homozygous) produced Pink flowered plant in F₁ generation.

Reason (R): In this plant, flower colour is controlled by pleiotropic genes.

(A) If both A and R are true and R is the correct explanation of A.

(B) If both A and R are true and R is not the correct explanation of A.

(C) If A is true and R is false.

(D) If both A and R are false.

Answer 1

(C) If A is true and R is false.

Mirabilis jalapa (4 O’ clock plant) exhibits Incomplete dominance. Both the genes of an allelomorphic pair, i.e. Red (R) and White (r) express themselves partially. Thus, the F₁ hybrid is Pink flowered plant which is intermediate between the Red and White varieties.