Presentation From Lavender

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Presentation From Lavender
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Video on seed dispersal

• http//www.youtube.com/watch?vzbQ1jWl3AOM

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Other methods on dispersal

• In order to deal with the realities of dispersal,
  plants have evolved specific structures and
  strategies to carry their seeds throughout the
  environment. Some seeds have two lateral wings to
  help them glide. Dandelions and salsifies use
  umbrella-like parachutes instead. Other seeds are
  known as "helicopters" or "whirlybirds" because
  they have spinning wings.
• 2. The wind is not the only method for seed
  dispersal. Seeds also can hitch rides on animals,
  preferably winged animals such as insects, bats
  and birds, as they usually travel the greatest
  distances. Other methods include travel by water
  and "ballistics" that fling seeds away from the
  plant at great speeds.

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Why Is Seed Dispersal Important To Plants?

• After plants have already fertilized and grown
  seeds, dispersal is the last important step
  before the new offspring finally establish
  independence on their own. There are a number of
  reasons why seed dispersal is integral to the
  survival of a plant species, but the methods of
  dispersal are varied.

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• Before they can grow into new plants, seeds need
  to leave the seed pod. If all the seeds a plant
  produced landed just underneath the parent plant,
  they would be too crowded, and the established
  large plant might not leave them enough light or
  water for them all to develop properly. When you
  plant seeds too thickly in a pot, you can see
  that they grow tall and leggy, and each plant is
  weak and spindly. The various methods of seed
  dispersal are designed to ensure that as many
  seeds as possible have a good chance of growing
  up to produce seeds of their own.

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• On some plants native to Australia and South
  Africa, the seedpods may need the heat of the
  natural bush fires occurring in these areas to
  open and release their seeds, which are then
  dispersed by other means.

                         
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• Sometimes, the pod or fruit containing the seeds
  is carried away from the parent plant sometimes,
  individual seeds are spread to a new location.
  The size and shape of the seedpod or the seeds
  influences how they are dispersed. The main
  methods plants use to disperse their seeds to
  places with better growing conditions than
  directly under the parent plant include gravity,
  animals, force, wind and water. Often, a plant
  will spread its seeds by a combination of these
  methods. For instance, a fruit falling to the
  ground by gravity might then be carried away by
  animals, or a seed blown by the wind might land
  in water and be transported somewhere else before
  germinating.

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Quiz time!!!!!

• Q1Name 1 type of dispersal of seeds.
• Ans Water/ Force/ Wind/ Animal/ Splitting/
  Gravity
• Q2 What does the seed need to leave first before
  it can grow into a new plant?
• AnsThe seed pod

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Quiz time!!!!!

• Q3Are individual seeds spread to a new location?
• Ans Yes
• Q4what will happen when the seed is fertilised
  and grown seeds?
• Ansdispersal

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By Khee Ing , Azmina ,Ryan ,Justin.?

• Thank you for listening to our presentation