Gender

• In some species of angiosperms, the flower contains both sex organs. In others, separate male and female flowers may grow on the same plant. Still other species produce completely separate male and female plants.
  
  

Pollen

• The stamen is the male organ of the flower. While stamens vary in size and shape, depending on the species of plant, they usually hold an anther at the end. The anther makes pollen, a powdery substance that carries the sperm cells of the plant.
  
  

Female Organs

• In the center of the plant is the female sex organ, called the pistil. The pistil is made up of the stigma at the tip, and the style, which extends from the stigma to the ovary at the base of the flower. Within the ovary are ovules that eventually become seeds.
  
  

Pollination

• In some angiosperms pollination occurs spontaneously, without the help of external forces. In other species, help is required. Wind, rain or physical interaction with animal species, such as honey bees, provide means of pollination.
  
  

Fertilization

• The stigma, the exposed area the end of the pistil, is coated with a sticky substance that captures any pollen grains that touch it. Sperm cells leave the pollen grains and travel through the stigma and style into the ovary.
  
  

Seed Development

• Once in the ovary, the sperm cells bond with the ovules to complete the fertilization process. The petals and stamens eventualy fall off, and the ovary grows to form a seed pod of some type. The ovules mature into seeds that eventually will be disbursed to propagate the plant.