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The Parts of a Flower
Most flowers are pollinated. When flowers are pollinated, pollen
must get to the top of the pistil. Some flowers are pollinated by the wind.
Others are pollinated by insects. Bees pollinate many kinds of flowers as they
feed on nectar and pollen. They go from flower to flower. They get food from the
flowers they visit. A bee’s hairy body picks up pollen in one flower. In the
next flower some of the pollen falls off. Some falls on the top of the pistil.
The top of the pistil is covered with a sticky substance. Pollen looks and feels
like fine dust. It is made of tiny, tiny grains. Through a microscope we can see
the shape of pollen grains. Pollen grains stick to the top of the pistil. Each
grain sends down a long, thin tube. The tube goes down inside the pistil. It
goes into one of the ovules. Material from the pollen grain moves down the tube
to the ovule. The ovule then grows into a seed. The pistil grows as the seeds
grow. It becomes a fruit. It holds the plant’s seeds. Flowers that are
pollinated have seeds. Seeds with One PartSome plants, such as corn, wheat, and rice, have seeds with only one part, called monocotyledons, or monocots for short. It is harder to split these apart to find the young plant. But whether a seed has one part or two, it contains food for the young plant to use until it is ready to make its own. The tulip, trillium, and iris are flowers that come from seeds with one part. Almost all seeds with one part form plants with flower parts (petals & stamens) in groups of three, such as 3, 6, or 9. Seeds with Two PartsThe wild rose, evening primrose, and violet are flowers that grow from seeds having two halves, called dicotyledons, or dicots for short. Most seeds with two parts form plants with flower parts (petals & stamens) in groups of 2, 4, or 5. Stems
The stems of plants are really transportation systems. Some tubes in the
stem carry water and minerals from the roots to the leaves. The leaves make
food. There are other tubes which carry food from the leaves to the rest of the
plant. Both kinds of tubes are usually found together in bundles in the stem. Leaves
Dicots have leaves with the veins in a network. Monocots have leaves with
veins that are parallel.
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