This tissue becomes the endosperm, which is utilized by the developing sporophyte. Flowers are modified leaves. These may resemble the showy petals, but often are small, green structures. Collectively, the sepals are called the calyx . Petals are the showy portion that we usually think of as the flower.
Petals act to attract pollinators to the plant.
Collectively, the petals are called the corolla. The next layer in contains the male parts of the flower, which are called stamens . The male parts of the flower are sometimes collectively called the androecium . The innermost layer of a flower is the female portion, which consists of three parts. A pistil contains one or more carpels , which enclose one or more ovules.