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• Reproduction – process of producing new organism of the same species
• Asexual reproduction – only one parent is involved
• Binary fission – single cell divides into two daughter cells which are nearly equal in size and ability to grow. E.g. binary fission in amoeba
• Multiple fission – During unfavourable environment, the amoeba becomes almost round and forms a hard covering around the cell called cyst. In Cyst nucleus divides into many Daughter Nuclei by repeated division.
• Budding – The nucleus of parent cell divides forms outgrowth on the cell body called as bud. The bud Increases in Size, Separates and Grows further. This type of reproduction is called Budding.
• Asexual reproduction in multicellular organisms
  • Fragmentation – Spirogyra grows and multiply rapidly in presence of water and nutrients and the filament of spirogyra undergoes fragmentation thus numerous new filaments are produced. These filament grows and develops into Mature Filaments.
  • Regeneration – Organisms have ability to grow into separate individuals from pieces of their body called as regeneration. E.g. planaria
  • Vegetative propagation – Vegetative parts of the plants are roots, stems, leaves and buds. When new plant is formed from these parts then the mode of reproduction is vegetative propagation.e.g. Reproduction in potatoes
  • Spore formation – Organisms like Rhizopus develops a blob-on-a-stick structures called as Sporangia which contains spores. Spores get nourishment inside the sporangia. That can grow into new Rhizopus individuals. Spores are protected by thick wall until they come in contact with moist surface then they starts growing.
• Parts of flower:
  • In plants, flowers are a functional unit with regards to sexual reproduction. Various parts of flower are
  • Carpel: It is a Female Reproductive Part of flower. It is present in the center of the flower. It is made up of stigma, style and ovary. Stigma is Sticky Terminal Part where Pollen Grains germinate. Style is Middle Elongated Part on top of which stigma is located. Ovary is Swollen Bottom Part contains Ovules. Ovules contains female germ cell called as Egg Cell.
  • Stamen: It is a male reproductive part of flower. It is made up of two parts anther and Filament. Anther is a bilobed i.e. it has two parts. Anther produces Pollen Grains. Pollen grains produce Male germ cells. Filament is a Supportive part of anther.
  • Sepal: The sepals are green-leaf like structures that protects the developing flower bud.
  • Petal: The petals are colourful structures of flower. These attract insects for Pollination.
• Unisexual flowers – flowers having either male or female reproductive organ are unisexual flowers.
• Bisexual flowers – flowers having both male and female reproductive organs are bisexual flowers
• Sexual reproduction in plants
  • Pollination – transfer of pollen grain from anther to stigma
  • Self pollination – transfer of pollen grain in same flower or different flowers of the same plant
  • Cross pollination – transfer of pollen grain from one flower to another flower of different plants is cross pollination
  • Fertilization – Pollen grains land on stigma of the flower and a pollen tube starts growing out from the pollen grain. Pollen tube grows towards the ovary through the style. Each pollen tube carry two male gametes. These male gametes are released near the egg i.e. female germ cell. One male gamete fuses with egg cell to form zygote which later divides multiple times to form embryo. Another male gamete fuses with secondary nucleus in the embryo sac to form endosperm which act as food store for the developing embryo. Since fertilisation occurs twice thus fertilisation in plants is called double fertilisation.
• Seed dispersal – transportation of seed away from the parent plant is called seed dispersal
• Modes of seed dispersal
  • Seed dispersal by wind
  • Seed dispersal by floating on water
  • Seed dispersal by animals
  • Seed dispersal by bursting