Flowers
Home Up Energy & Growth Flowers Other Plants Plant Behavior

 

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.
           
Every kind of flower has its own kind of pollen. The pollen grains of daisies will help make only daisy seeds. The pollen grains of apple blossoms will help make only apple seeds.

 

Seeds with One Part

            Some 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 Parts

            The 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.
           
Dicot stems. In a dicot stem the bundles of tubes are arranged in a ring around the edge of the stem. As the dicot stem grows older, it forms a new ring of tubes every year. Dicot trees get thicker each year by adding a new layer of tubes. Some of last year’s layer becomes wood. The layers look like rings when the stem is cut across. Each year a new layer of wood is added.
           
Monocot stems. In a monocot stem the bundles of tubes are scattered throughout the stem. In monocots the bundles of tubes stay scattered, even when the plant gets older. The tubes get larger, but no new layers are added.

 

Leaves

            Dicots have leaves with the veins in a network. Monocots have leaves with veins that are parallel.