A corolla is the ring of petals on a flower, the part that's usually the most colorful and eye-catching. When you look at a daisy, rose, or tulip, the corolla is what you're admiring: those delicate petals arranged in a circle around the flower's center.

The corolla serves a crucial purpose beyond looking beautiful. Those bright colors and interesting shapes attract bees, butterflies, and hummingbirds, which help the flower reproduce by carrying pollen from one flower to another. A sunflower's yellow petals form its corolla, while a rose's soft red or pink petals create its corolla.

Different flowers have dramatically different corollas. Some are simple, with just a few petals arranged in a basic pattern. Others are elaborate, with dozens of overlapping petals in complex formations. The shape and color of a corolla help scientists identify what kind of flower they're looking at.

Scientists distinguish the corolla from the calyx, which is the ring of small green leaflike parts (called sepals) that you can see at the base of many flowers, protecting the flower bud before it opens. Together, the corolla and calyx make up the perianth, which is the non-reproductive part of the flower that protects and advertises.