Plants

1
Plants

• Water Transport and Reproduction

2
How water moves into a plants roots and up the
stem

• Root pressure The pressure created when water
  enters the tissues of the root of plants.
• This pressure is not enough however to move the
  water up a very tall plant or tree. In order to
  move water over a long distance the tree needs
• Capillary action
• transpiration

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How water moves up a plants stem

• Capillary Action The tendency of water to rise
  in a thin tube.
• Water molecules are attracted to one another by a
  force called cohesion.
• When water molecules are attracted to another
  substance that is called adhesion.

4
Transpiration

• Transpiration the evaporation of water from the
  leaves of plants.
• This process causes osmosis to occur.
• When the water leaves the leaves it causes a pull
  from below of water in through the roots.

evaporation
Pulling of water
5
Life cycle of Gymnosperms

• They produce 2 types of cones.
• 1. pollen cones
• 2. seed cones
• Reproduction takes place inside the cones.

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Pollen Cones

• Male cones
• Produce the male gametophytes called pollen
  grains.
• The pollen grain will then divide into two sperm
  nuclei.

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Seed Cones

• Female cones
• Produce the female gametophytes
• Much larger then pollen cones
• In the cone at the base of each scale there are 2
  ovules.
• These ovules contains hundreds of thousands of
  cells.
• When the gametophytes mature they are ready for
  fertilization.

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Pollination

• Takes 2 years to complete
• Males release enormous numbers of pollen grains.
• Pollen is carried by the wind, insects, and birds
  to the female cones.

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Fertilization Development

• If a pollen grain lands near a female ovule, the
  grain splits open and grows a pollen tube.
• The pollen tube grows until it is large enough to
  reach the female egg.
• The seed is created from the joining of both male
  and female gametophytes.

10
Flowers and their parts

• Sepals The tiny leaf like structure at the base
  of the flower.
• Enclose the bud before it opens
• Petals Brightly colored found inside sepal.
• Attract insects and other pollinators to the
  flower.

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Flowers and their parts continued

• Stamen The male part
• Contains the anther and filament
• Filament long thick stalk that supports the
  anther.
• Anther oval sac that produces pollen grains
  (gametophytes)
• Carpel The female part
• Contains the ovary, style, stigma

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Life Cycles of Angiosperms

• Reproduction takes place inside the flower.