NEETBotanyMorphology of Flowering Plants
Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): Flowers of pea and bean exhibit zygomorphic symmetry and vexillary aestivation. Reason (R): In these flowers, the largest standard petal overlaps the two lateral wing petals, which in turn overlap the two smallest anterior keel petals. In the light of the above statements, choose the most appropria
Options
- ABoth (A) and (R) are correct and (R) is the correct explanation of (A)
- BBoth (A) and (R) are correct but (R) is not the correct explanation of (A)
- C(A) is correct but (R) is not correct
- D(A) is not correct but (R) is correct
Correct answer
A. Both (A) and (R) are correct and (R) is the correct explanation of (A)
Step-by-step solution
Assertion (A) is correct: Pea and bean flowers are zygomorphic (bilaterally symmetrical) and show vexillary aestivation (papilionaceous corolla). Reason (R) is correct and correctly explains (A): The specific arrangement described in (R) defines vexillary aestivation. Because the petals are of unequal sizes and arranged in this specific overlapping manner (one standard, two wings, two keel petals), the flower can only be divided into two equal halves through one particular vertical plane, which makes it zygomorphic