Parts of a Flower

Flowers Flowers are the reproductive structures of a flowering plant.  Flowers are the primary structures used in grouping plant families. Function: Reproduction – beginning with pollination and fertilization Advertisements and rewards to lure pollinators

Parts of a Flower A flower is made up of rings The outermost ring is made of SEPAL The next ring inside of the sepal are the PETALS Inside the petals are a ring of STAMEN And last, in the CENTER of the flower is the PISTIL

Pistil Stigma – Sticky surface on top of pistil that traps pollen The Pistil is the Female reproductive organ of a flower. The Pistil produces the Female sex cells called ovules (egg cells). Stigma – Sticky surface on top of pistil that traps pollen Style – Tube-like structure that connects stigma to ovary Ovary – Found at bottom of flower, contains ovules. Turns into fruit. Ovules – Female sex cells that gets fertilized by pollen

Ovules Pistil Stigma Style Ovary

Stamen Stamen are the Male reproductive organs of a flower. The stamen produce the Male sex cells called pollen cells. Anther – Located on top of the stamen, pollen is created and stored here Filament – Located on the stamen, thread-like stalk that supports anther

Ovary Ovules Stamen Anther Filament

Petals Usually colorful petal-like structures making up the “flower” Surrounds reproductive structures Collectively called the corolla   They may contain perfume and nectar glands. 

Ovary Petals Ovules

Sepals Sepal are found at the base of the flower Sepal look like green petals Sepals help protect the developing bud Collectively called calyx

Sepals Ovary Ovules

Perfect Flower vs. Imperfect Flower Perfect Flower- Both male and female reproductive parts are found on the flower Imperfect Flower – Only male or female parts are found on a flower Pistillate  – Flowers containing only female parts Staminate – Flowers containing only male parts

Pollen Male sex cell Normally a powder found on the anther A sugary substance that attracts insects Pollination is the act of transferring pollen grains from the male anther of a flower to the female stigma Seeds can only be produced when pollen is transferred between flowers of the same species

How does pollen get from one flower get from one flower to another? Flowers must rely on vectors to move pollen. These vectors can include wind, Water Birds Insects Butterflies Bats other animals that visit flowers. We call animals or insects that transfer pollen from plant to plant “pollinators”.

Pollination Pollination is usually the unintended consequence of an animal’s activity on a flower Pollen from the anthers of Flower 1 is deposited on the stigma of Flower 2. 0nce on the stigma, pollen may “germinate,” which means that a “pollen tube” forms on the sticky surface of the stigma and grows down into the ovule of the plant. This growth can result in: Successful fertilization (pollen unites with ovule) of the flower and the growth of seeds and fruit; or, A plant can be only partially fertilized, in which the fruit and/or seeds do not fully develop; or, The plant can completely fail to be pollinated, and may not reproduce at all.

Self Pollination vs. Cross Pollination Self-pollinating - the plant can fertilize itself Cross-pollinating - the plant needs a vector (a pollinator or the wind) to get the pollen to another flower of the same species.

Sexual reproduction in a flowering plant has FOUR main stages Pollination: This is when pollen lands on a new flower Fertilization: This is when the pollen and ovules meet to create a seed Seed dispersal: This is when the seed is spread around, away from the plant that made it Germination : This is when the seed opens up and begins to sprout.