Twisted aestivation is characterized by sepals or petals doing what?

• A. They just touch at margins without overlapping
• B. They are fused at the base
• C. They overlap one another in any direction
• D. They overlap one another in a pattern/a particular direction

Answer: (D)

Aestivation patterns describe how the sepals or petals come together in the bud before opening. Twisted aestivation means each petal or sepal overlaps the next in a consistent direction around the circle, so the edges form a twisting, helical arrangement as the flower opens. This specific directional overlap creates the visible twist, distinguishing it from other patterns. It’s not just edges touching (that’s valvate), nor is it about fusion at the base, and it isn’t the broad, direction-agnostic overlap of general imbrication. So the key idea is that the petals or sepals overlap one another in a pattern following a particular direction, producing the twist.