NEET BIOLOGY

Detailed explanation-1: -Vexillum is used to refer to the standard, large posterior petals of papilionaceous flowers (corolla). The posterior large bilobed petal of the papilionaceous corolla is called standard or vexillum. They overlap the two smaller lateral petals known as alae or wings.

Detailed explanation-2: -So, the correct answer is ‘Papilionaceae’.

Detailed explanation-3: -The vexillum or standard, the outermost posterior petal, is large, two lateral petals are known as the wings or alae, and the two anterior and innermost petals are fused to form a boat-shaped structure known as the keel or carina in vexillary aestivation. As a result, vexillum is found in the Papilionaceae family.

Detailed explanation-4: -Vexillary aestivation is the special arrangement where one large petal covers the other smaller petals. The two innermost, boat-shaped petals are called keels in this aestivation. The plants of Papilionaceae or legume family exhibit the ideal examples of vexillary aestivation.

Detailed explanation-5: -In the Fabaceae family vexillary aestivation is found. Vexillary aestivation is the arrangement of petals where the smaller petals are covered by one large petal. Vexillum is the larger petal, while the two curved petals which are laterally positioned are called wings. Keels are the two inmost boat-shaped petals.