Question

A corolla of five petals with vexillary aestivation is said to be-
A. Igulate
B. Bilabiate
C. Personate
D. Papilionaceous

Answer 1

Hint:-A plant's reproductive organs are flowers. Modified leaves that cover the reproductive parts of flowers are petals. Together, all of a flower's petals are named as corolla.

Complete step-by-step solution:-
Option A is incorrect. The Corolla in Asteraceae or Compositae is irregular and gamopetalous. It is ligulate, which occurs in the form of a strap or ray. They are zygomorphic and have a shape resembling a narrow tunnel. They could also have a flat upper section, e.g., Compositae ray florets.
Option B is incorrect. A zygomorphic, sympetalous corolla with the limb split into two lips is a bilabiate (means 'two-lipped') corolla. Usually, lamiaceae (the mint family) have bilabiate corollas. Zygomorphic, gamopetalous corolla, in which the petals are so fused together that two separate lips, e.g. Adhatoda, Ocimum, tend to be separated.
Option C is incorrect. Personate corolla is also known as masked or bilabiate corolla, but since two lips are very similar to each other, e.g. Linaria, the corolla's mouth is closed here.
Option D is correct. Papilionaceous flowers are flowers found in the plants of the subfamily of legume species with the distinctive irregular and butterfly-like corolla. The flowers have a bilateral corolla symmetry consisting of five vexillary aestivation petals. With its five petals arranged to resemble a butterfly, it is an irregular, polypetalous corolla. It consists, as in Papilionaceae members, of a posterior major vexillari, two lateral 'alae' and two anterior fused petals called 'keel.'
So, the correct answer is Option D.

Note:- The second axillary whorl consisting of petals is the Corolla. The corolla also protects the more important stamens and carpels inside, like the calyx. Usually brightly coloured or white, the petals that make up the corolla attract insects and birds for pollination.