Plant Reproduction and Pollination

Plant Reproduction

• Plants reproduce sexually and asexually to pass on their genes.
• Sexual reproduction involves two parents contributing genetic material (DNA).
• Gametes (sex cells) from parent plants combine in fertilization.
• Seeds produced are not identical to either parent.
• This genetic diversity increases survival.

Sexual Reproduction in Flowering Plants

• Sexual reproduction in flowering plants is called pollination.
• Flowers contain male (stamen) and female (pistil) reproductive organs.
• The stamen has an anther (containing pollen - male gametes) and a filament.
• The pistil has an ovary (containing ovules or eggs), a style, and a stigma.
• Pollen must be transferred to the stigma for fertilization.

Pollination Methods

• Self-pollination: a plant's own pollen fertilizes its ovules.
• Cross-pollination: pollen from one plant is transferred to another.
• Cross-pollination increases genetic diversity.
• Pollinators (e.g., bees, butterflies, birds) move pollen between plants.
• Flowers' colors and scents attract pollinators.

Fertilization and Fruit Development

• Fertilization: male gametes (pollen) join with female gametes (egg or ovules).
• Fertilization forms fruit containing seeds.
• Fruits vary in form, e.g., fleshy (oranges), dry (acorns).
• Animals disperse seeds when eating fruit.

Asexual Reproduction

• Asexual reproduction involves one parent and creates genetically identical offspring (clones).
• Clones lack genetic diversity, reducing adaptability and disease resistance.
• Methods include vegetative propagation and fragmentation.
• Vegetative propagation produces offspring from plant parts, e.g., tubers, corms, rhizomes.
• Fragmentation: new plants grow from broken parts of parent plants, e.g., liverworts, mosses
• Apomixis: some plants produce seeds without fertilization.

Additional Notes

• Not all plants have large, brightly coloured flowers (e.g., grasses).
• Some flowering plants are angiosperms, and others are non-flowering (e.g., mosses, ferns, conifers).
• Horticulturists use asexual reproduction (e.g., cuttings) to propagate new plants.
• Coco de mer seeds are the largest of any plant.