Plant Science Week 5

Flowers are found in many kinds of shapes, colors and petal display

Monocot flowers Wheat flowers Wheat flowers are not so attractive, but there is hope…… check out the Easter lily, which is also a monocot flower

Flowers Most flowers have four basic components: Sepals Petals Stamens Pistil

Sepals The outer most covering of a flower bud Protect internal parts of flower Fold back when flower opens and helps support it Individual sepals grouped together are known as the calyx

Petals Brightly colored modified leaves found in a circle just inside the calyx Attract insect pollinators because they secrete aromatic liquid, nectar Individual petals grouped together are known as the corolla

Stamens Male reproductive apparatus found just inside of corolla Consists of anther and filament Anther is a pollen producing structure Pollen, a yellowish powder, contains sperm cells Filament supports and lifts anther

Pistil The female reproductive organ, consisting of stigma, style and ovary, usually in the center of the flower, surrounded by the stamens Topped by a sticky structure known as stigma where the pollen lands Bottom of the pistil is a swollen base, the ovary, where seeds form from fertilized ovules Connecting the stigma and ovary is the style

Pollination and Fertilization Pollination is the transfer of pollen from an anther to a stigma and fertilization is the uniting of a sperm with an egg.

Let’s look at this flower again in terms of pollination and fertilization The pistil is The entire Female Reproductive apparatus The stamen is the Entire male Reproductive apparatus

Some Definitions Flower Reproductive organ of the plant Female reproductive structure of a flower composed of one/more carpels Pistil Anther A part of the stamen that produces pollen Filament The stalk that supports the anther Stamen The filament and anther together Pedicel The stalk of an individual flower (in an inflorescence) Recepticle The swollen tip of the pedicel where the flower parts are attached Sepal One of the parts of the calyx Stigma The sticky tip of the pistil Style A column of tissue that connects the ovary and stigma Ovary The structure that contains ovules

The part of the anther that produces pollen Pollen sac The part of the anther that produces pollen Pollen The small, light, powdery grains that contain male cells Inflorescence A group of flowers, in a definite arrangement on an axis Peduncle The stalk of an inflorescence, or of an individual flower