Sepals and the underside of the petals of the Sunflower (Helianthus annuus).

What does the sepal do in a sunflower?

A sepal (/ˈsɛpəl/ or /ˈsiːpəl/) is a part of the flower of angiosperms (flowering plants). Usually green, sepals typically function as protection for the flower in bud, and often as support for the petals when in bloom.

What are sunflowers petals called?

In the common sunflower, the outer yellow petals are called ray flowers, and the center is composed of numerous disk flowers crowded together. The entire head is subtended by numerous green bracts called phyllaries.