Question

Match the aestivation patterns.

• A. Imbricate
• B. Vexillary
• C. Twisted

Answer 1

The mode of arrangement of sepals or petals in a floral bud with respect to the other members of the same whorl is known as aestivation. The main types of aestivation are valvate, twisted, imbricate, quincuncial and vexillary.

A. When sepals or petals in a whorl just touch one another at the margin, without overlapping, it is said to be valvate.
B. If one margin of the appendage overlaps that of the next one and so on as in china rose, it is called twisted.
C. If the margins of sepals or petals overlap one another but not in any particular direction, the aestivation is called imbricate.
D. Quincuncial aestivation is generally seen in pentamerous flowers with five petals. Two petals have both edges on the exterior or overlapping, two have both ends interior and the fifth petal has one exterior edge and one interior edge.
E. In pea and bean flowers, there are five petals of unequal sizes, the largest (standard) overlaps the two lateral petals (wings) which in turn overlap the two smallest anterior petals (keel); this type of aestivation is known as vexillary or papilionaceous.