Inside the bud, a tiny but complete flower forms. The sepals protect the bud before it opens. Over time, the bud opens and blossoms into a mature flower and the sepals look like little green leaves at the base of the flower. The flower is the sexually reproductive part of the plant. The petals of the flower are often very noticeable, brightly colored, and strongly scented in order to attract pollinators. This is a very exciting stage of the plant life cycle!
The plant life cycle starts with a seed; every seed holds a miniature plant called the embryo. There are two types of flowering plant seeds: dicots and monocots. An example of a dicot is a bean seed. It has two parts called cotyledons in addition to the embryo. The cotyledons store food for the plant. Cotyledons are also the first leaves that a plant has-they emerge from the ground during germination. Monocots have only one cotyledon-the corn seed is an example. Both kinds of seeds have the beginnings of a root system as well. The hard outside of the seed is called the seed coat and it protects the embryo. Some seeds are capable of growing even after many years if they are kept cool and dry.
The plant life cycle starts when a seed falls on the ground. There are many different kinds of plant life, but the flowering plants, or angiosperms, are the most advanced and widespread due to their amazing ability to attract pollinators and spread seeds. Flowers are more than beautiful objects to look at or decorate with; they serve a very important purpose in the reproduction of plants. The major stages of the flower life cycle are the seed, germination, growth, reproduction, pollination, and seed spreading stages.
When a seed falls on the ground, it needs warmth and water in order to germinate; some seeds also need light. Dicots have seed coats that soften with moisture. After being planted in the soil for a few days, the seed absorbs water and swells until the seed coat splits. Monocots have harder seed coats that do not split, but stay in one piece. The stem, called the hypocotyl, pushes through the soil along with the cotyledons, or seed leaves; this is called germination, or sprouting. The tiny root pushes down and grows, looking for water and nutrients. Soon the cotyledons fall off and the first true leaves emerge. It is important that the seed is planted in the right place at the right time in order for it to germinate. Some seeds need to go through a fire in order to sprout, such as prairie grasses. Some need to go through the stomachs of animals, or be scraped. Different seeds have different needs!
Some flowers have only male parts, and some have only female parts. In others, the male and female structures are far apart. These plants depend on insects, birds, animals, wind, water, or other pollinators to carry pollen from the male flowers or male parts to the female flowers or female parts. Without pollinators, there would be no seeds or new plants in these plant species. . Even flowers that can self-pollinate benefit from being fertilized by pollen from a different plant, which is called cross pollination, because cross pollination results in stronger plants.
Learn about all of the different stages in the growth cycle of a flower, from seed to bloom and beyond.