Flower Anatomy

• The style supports the stigma, while the ovary contains one or more ovaries where seeds develop from fertilized eggs.
• Ovules are found on the inner walls of the ovary.
• The receptive surface is the stigma.
• • The anther and the filament makes up the stamen (the flower's 'male' sex organ).
  • The stigma, style, ovary and ovules make up the carpel (the flower's 'female' sex organ).
• A flower with both male and female parts is called perfect.
• Flowers that have only male or female parts are imperfect flowers.
• Flowers that have only male or female parts are imperfect flowers.
• The sepal protects the flower bud when it is developing.
• The petal attracts insect pollinators to the flower.
• Pollen grains are produced by the anthers.
• The stamen produces pollen grains which contain sperm cells.
• Reproduction in Plants:

  
• Self-pollination

  • Self-pollination happens when pollen from an anther is transferred to the stigma of the same or a different flower on the same plant.
  • The offspring produced are identical to the parent plant, so a disadvantage of this is a lack of genetic variation.
  • An advantage of this is that if a plant is not able to reproduce by cross-pollinating (there are no pollinators nearby), they can still reproduce through self-pollination.
• Cross-pollination

  • Cross-pollination is the transfer of pollen from the anther of one flower to the stigma of a flower on a different plant.
  • This introduces genetic variation into the offspring, so they are able to respond to the environmental changes.
• Fertilization

  • After pollination, a structure called a pollen tube grows out of the pollen grain down the style.
  • The male gamete travels down the pollen tube to the ovule inside the ovary.
  • Fertilization is when the nucleus of a male gamete fuses with the nucleus of a female gamete (the ovule).