Flowers are the reproductive organs of angiosperms, plants that produce seeds in an enclosed structure. A flower is a special type of plant part, and flowers are also called bloom or blossom. Flowers are beautiful to look at and they have a sweet smell. Some flowers can be eaten, and some flowers are used to make medicines.
The parts of a flower are the petals, stamens, pistils, and sepals. The petals are usually the showiest part of the flower, and they attract insects or other animals to pollinate the flower. The stamens are the male parts of the flower; they produce pollen grains that contain the male gametes (sperm cells). The pistils are the female parts of the flower; they receive pollen grains and produce ovules (egg cells). The sepals protected the bud before it blooms.
Most flowers bloom in springtime, but there are some that bloom in summer or autumn. Bulbs such as daffodils and tulips need a period of cold weather (winter) before they will bloom. This is called vernalization . Some desert plants such as cacti only bloom after a rainstorm because their seeds require water to germinate .
The main purpose of a flower is reproduction . To do this, flowers use pollination . Pollination is when pollen from the male parts (stamen) gets transferred to the female parts (pistil). This can happen in different ways: by wind , by water , or by animals such as birds , bees , butterflies , moths , flies , wasps , beetles , bats , monkeys , lemurs , possums , rodents ; even lizards and snakes ! When pollination happens, fertilization takes place and this is when the egg cell(s) inside the pistil(s) get(s) fertilized with sperm cell(s), forming a seed . Once fertilization occurs, fruits and vegetables can develop – these contain seeds too!