Flowers are an important part of many plants. Plants use flowers to make other plants – to reproduce. Flowers have special parts, called stamens and pistils. When pollen from the stamen finds its way down through the pistil, the flower is pollinated, and seeds start to grow. The seeds eventually find their way to the ground, the seeds sprout, and more plants are born.
Plants have all different styles of flowers. Some flowers have patterns on them that guide bees and other insects to the pollen. Wheat flowers are long and stringy, so when the wind blows, pollen can float easily from stamen to pistil. Some flowers even smell like rotting meat to attract flies. The flies land, pick up pollen on their legs, and dust some of it onto the flowers’ pistils. Although flowers have different shapes, colors, and smells, all flowers make seeds to keep the plant population growing.
Every flower consists of a set of adaptations that help to ensure successful reproduction. For example, flowers often have bright colors, attractive shapes, and pleasing aromas. These traits help them attract insects and other animals that
will carry pollen grains from flower to flower. Pollination also occurs by means other than animals carrying the pollen. For some flowering plants, the wind plays an important role in transferring pollen from plant to plant.
The seed-bearing plants that produce flowers are called angiosperms. The flower produces the seeds, each of which contains a new plant embryo. The parts of the flower are usually found in four whorls, or rings. Petals are one of the four whorls. They attract pollinators. Sepals lie outside the petals. They protect the bud.
The reproductive organs, the stamens and pistils, make up the third and fourth whorls and lie inside the petals. A stamen is a male reproductive part. It consists of an anther that is held up by a filament. The anther produces pollen grains. A pistil is a female reproductive part. Its top is called the stigma. It is sticky to ensure that when pollen grains land on it, they stick to it. The middle supporting structure is the style, and the large base is the ovary, where the eggs are produced.
1. Bill Nye - Flowers! video
23 minutes - 23 points!
2. Go outside and find 7 flowers (different kinds!) -- locate the stamen and the pistil on each flower. 7 points.
3. Read Chapter 3, section 1 - about Gregor Mendel and his famous flying peas. 20 points.
50 points possible!
[Do you crave more science videos? Here's "The Biggest Flower in the World": https://www.youtube.com/watch?v=FHaWu2rcP94&list=PL47D0521D98A9EF1D&index=8]
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