Plants - Download as PowerPoint by pengxiang

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 An Overview of
 What are Plants?
 Trees ,flowers,
  vegetables, fruits, field
  crops like wheat, rice,
 Some plants are food
  sources for human.
 Without plants most life
  on earth is not possible.
Plant Characteristics

 Plants range in size from    Desert Paintbrush

  microscopic water ferns
  to giant sequoia
 They adapted to nearly       Desert Sunflower
  every environment (frigid,
  ice bond polar regions
  and others grow in hot
  dry deserts.
                               Desert Willow
 Plant Cells
 A plant cell has cell
  membrane, a nucleus, and
  other cellular structures.
  They have cell walls that
  makes them different than
  animal cells.
 Plant cells contain
  chlorophyll. It is found in
  chloroplast (Green).
 They have vacuole that
  stores pigment and regulates
Origin and Evolution of Plants

 The ancestors were probably
  ancient green algae that lived in
 Today, plants and green algae
  have the same types of
  chlorophyll and carotenoids that
  red, yellow, orange.
 Fossils are not good clue for
  plants. They usually decay
  before they become fossilize.
  Cooksonia a fissile of one of
  these plants.
 Exact origin of flowering plants
  is not known.
  Life on Land
 Earth has more sunlight and
  CO2 for Photosynthesis. Long
  time ago more plant adapted
  to land easily.
 Plants give off oxygen. This
  paved the way for organism
  that depends on Oxygen.
 Shallow pool provides water to
  green algae to survive.
 They make processes of
 When it dries they dies. Water
  moves in and out. (Osmosis).
 Cuticle and Cellulose

 Stems ,leaves and flowers
  are covered by cuticle that is
  a waxy, protective layer
  secreted by cells onto
  surface of the plants.
 Cuticle slows loss of water.
 Cellulose is chemical
  compound that plants can
  make out of sugar. It forms
  tangled fibers in cell walls.
  These fibers provide
 structure and support.
 Some water resistant spores
  helps plant reproduce
 Other plants adapted by
  producing water resistant
  seeds in cones or in flowers
  that developed into fruits.
Classification of
 Vascular :have tube like
  structures that carry water
  and substances
 Nonvascular: Do not have
  tubelike structures.
 Scientist use Binomial
 Quesrcus Alba (White Oak)

 Plants are made up of stems root
  leaves flowers. What else?
 Most plants grow from seeds.
 What plants do not grow from seeds.
 They are thick and only 2cm and 5
  cm height.
 Most have stalks that look like stems
  and green, leaflike growths. (rhizoid)
 They absorb water and distributed to
  their cell membranes.
 They do not have flowers and
  reproduce by spores. Mosses,
  liverworts, hornworts.
 They have green, leaflike
  growths arranged around a
  central stalk.
 Their rhizoids are made of
  many cells.
 Stalks grow from moss parts.
 Spores are produced in the
  caps of these stalks.
 They are usually found in dump
  area and on tree trunks.

 They are thought
  to be useful in
  treating diseases
  of liver.
 Wort means “herb”
  liverwort means
  “herb for liver”
 They are leaflike
  flattened bodies.
 Most of them are less
  than 2.5 cm diameter
  and have flattened
  body. They have only
  one chloroplast in
  their each cell.
 Their spore producing
  structure is tiny horns
  of cattle.
 Nonvascular plants
 and The environment
 Mosses and liverwort can grow on
  long and dry periods , also grow
  in thin soil and in soils where the
  other plants do not grow.
 Their spores are carried out by
  wind. They start to grow easily.
  they are among the first plants to
  grow in new disturbed area.
 Organism that are the first to grow
  in new and disturbed areas are
 They build the soils therefore the
  other organism move in that area.
 Seedless Vascular plants
 Like ferns vascular
  seedless plant can
  grow big and thick
  because they can
  carry the water
  and minerals from
  soil to their leafs.
Club Mosses
 Ground pines and Spike mosses are
  groups of plants that often are called
  club mosses.
 Spores are produced at the end of
  stem in structures like pinecones.
  They are endangered.
 Spike mosses resemble ground
  pines. Some of them adapted to
  desert condition.
 When water us scarce they curls
  and unfurl seem dead. When water
  becomes available the resurrection
  plants unfurls its green leaves and
  making food again.
 The stem structure of horse
  tails is unique among the
  vascular plant. The stem is
  jointed and has a hollow center
  surrounded by a ring of
  vascular tissue.
 Spores are produced in
  conelike structure at the end of
 The stems of horsetail contain
  silica a gritty substance found
  in sand.
 Horsetail has been used fro
  polishing objects, sharpening,
  tools, and scouring cooking
Importance of Seedless
 Dead plants are turned into coal ( took
  million years )
 The same is process is happening on
  bogs which are poorly drained areas
  of land contain decaying plants.
 Overtime, slow decaying plants
  process without oxygen are
  compressed into substance called
 Peat is used for energy source in
  Russia and Ireland.
 Seedless vascular plants are used for
  gardening and medicine, Their root
  can be used for food source too.
 What did you eat
 Carrot, apple, watermelon,
  peanut butter?
 Most of plant you familiar
  with are seed plants that
  have leaves and stems
 They have seed that
  contain embryo and food.
 They are classified into two
 A) Gymnosperms
 B) Angiosperms
 They do photosynthesis with
 Upper and lower surface layer
  covered with thin layer called
  Epidermis ( cuticle coats)
 Small opening are called
  STOMATA (it allows plant to take
  in take out water CO2 and oxygen)
 Each stomata surrounded by two
  guard cells
 Below the upper layer is called
  PALISADE LAYER ( it is rich for
  chlorophyll) What does it mean?
  (2pt )
 Between palisade and lower
  epidermis is spongy layer.
 The trunk is really
  the stem.
 Materials move
  between root and
  leaves through the
  vascular tissue.
 Stems can be
  herbaceous( soft)
  or woody( hard,
 Water and other substances
  enter through tree from its
 It has vascular tissue
 Roots anchors to soil to prevent
  plant being blown away.
 They can be found above –
 Roots can store food. (carrots
  and beets)
 Plants use this stored food to
  grow. (Some store water)
 They perform absorbing oxygen
  such as plant which live in
Vascular tissue
 Three tissues
 A) Xylem: hollow tubular
  cells that are stacked one
  on top the other to from a
  structure called vessel. It
  transports dissolved
  materials and supports
  plant.                                                   tracheids
 B) Phloem: Tubular that
  are stacked to form
  structure called tubes.
  They move food.
 C) Cambium: produces
  most of the new xylem and
  phloem cells.
 The oldest trees. Bristlecone
  pine tree is 4900 years old.
 Gymnosperms are vascular
  plants that produce seeds that
  are not protected by fruit.(
  Naked seed) (They are
  needlelike green)
 They are classified A) conifers,(
  pines, firs, spruces, redwoods)
  B) cycads, C) ginkgoes, D)
 Conifers produce two types of
  cones ;Males and female. seeds
  develop on the female one.
 Angiosperm :A vascular plant
  that flowers and has fruit that
  contains one or more seeds.
 They grow everywhere. The
  fruits develops from a part or
  parts of one or more flowers
 Some plants flower are not
  recognized .they are nor
  colored. ( Ash flower)
 Some flower parts develop
  into fruit. Most fruits contain
  seed like apple. All fruits are
  nor juicy. The fruit of vanilla
Monocots and Dicots
 A cotyledon is part of
  seed ,used fro food
  storage. mono mean one
  di mean two.
 Many important foods
  come from monocots
  including corn rice wheat
  and barley. Lilies and
  orchids too.
 Dicots also produce
  familiar foods such as
  peanuts green beans,
  peas. apples., and
  oranges. maple, oak, elm
Life cycle of Angiospems
 Annuals complete life cycle in one growing season
 Biennials live for two seasons; flowers form in
   second season
 Perennials grow and produce seeds year after year

Figure 30.3 Winged seed of a   Fruit adaptations that enhance seed

White Pine (Pinus strobus)     dispersal: Red berries (left), dandelion (right)
Dandelion seed dispersal
Importance of seed plants

 •The most economically important plants on earth
 are the angiosperms. They form the basis of diets for
 most animals. grains barley, wheat, legumes, peas,
 •They are used to produce waxy substance resin that
 are used in soap, paint, varnish, and some

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