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					~   Algae
~   Bryophytes
~   Ferns
~   Angiosperms
~   Gymnosperms
Evolution
Algae
      This is a collective name for a varied group
    of phyla with no one diagnostic feature. They
    are normally aquatic or live in damp terrestrial
    habitats. Subdivisions are mainly associated
    with biochemical differences related to
    photosynthesis.
  Algae are without roots, stems or leaves.
  All contain chlorophyll and so can make
 their own food by photosynthesis.
 The cells are long and their cellulose cell
 walls are covered by a layer of mucilage.
 The major are green, but some are brown
 or red.
               Feature of plant
Vascular tissue    no
support            Air sac, by water
sporophyte         no
gametophyte        no
Stem root leave    no
Water absorption   diffusion
Reproduction       Binary fission
dispersal          swim
Structure of algae
diatom
     Type of algae
Green algae   Brown algae
Volvox
analipus   egregia
Bryophytes
- Bryophytes are small green plants with simple
  leaves, stems but no roots.
- They grow close to ground, and usually do not
  grow more than 2cm in length.
- They do not have vascular tissue which enables
  the plant to grow tall, and which they have no
  support to be stiff.
- They are anchored in the ground by delicate
  structure called Rhizoid.
- They live in damp places.
- The life cycle of Bryophytes begins with
  the release of haploid spores. Spores that
  geminate begin cell division, this produces
  the filament that will eventually form a
  gametophyte.
Photo of bryophytes
moss
liverwort
Life cycle of bryophytes
Archegonia
               Feature of plant
Vascular tissue    No true
support            turgid
sporophyte         Only capsule parasite
                   gametophyte
gametophyte        Photosynthetic, mainly
Stem root leave    No real root but rhizoid
Water absorption   diffusion
Reproduction       Sexually archegonia, antheridia
dispersal          Capsule dry up, mechanical
 Ferns
- Ferns consist of true stems, roots, leaves and vascular
tissues.
- Their roots grow horizontally underground
- The preferred habitat of a fern is in the wetlands, or
in moist woody areas; they also prefer damp shaded
area.
- They need water for fertilization.
- As for reproduction, they reproduce by spores and
vegetatively by rhizomes, which are horizontal
underground stems.
Photo of ferns
Life cycle of ferns
               Feature of plant
Vascular tissue   simple
support           tracheid
sporophyte        Major, large, water resistant
gametophyte       Minor, small
Stem root leave   Have but root is simple as rhizoid
Water absorption rhizoid
Reproduction      Gametophyte archegonia antheridia
dispersal         Sorus dry up mechanical
Gymnosperms(conifers)
 Gymnosperms are large evergreen trees
  with seeds growing inside cones for
  reproduction.
 Most of them have needle-shaped leaves.
 It does not have flowers but seeds. The
  seeds are naked. They are not enclosed in
  food and borne on structure called cones.
  Example is pine.
     In conifers, the region of primary cell wall
    in the centre of the pit is thickened with a
    deposit of waxy material, forming a
    structure known as a torus. The phloem of
    conifers contains sieve cells, fibres, and
    parenchyma cells, but companion cells are
    absent.
Examples of gymnosperms

               Pine
               Feature of plant
Vascular tissue    have
support            woody
sporophyte         all
gametophyte        Minimize to cone
Stem root leave    have
Water absorption   root
Reproduction       cone
dispersal          wind
Angiosperms
 All angiosperms have flowers for
  reproduction.
 Their seeds are produced inside the ovary.
 Angiosperms form the dominant terrestrial
  vegetation today.
 They are found in a wide range of habitats
  and have even re-established themselves in
  freshwater and the sea.
- They are extremely well
  suited to life on land
  both in their morphology.
- They are divided into
  dicotyledons and
  monocotyledons.
Morphology of herbaceous
dicotyledon
Morphology of herbaceous
monocotyledon
 Lily
Comparison of moncotyledoneae
and dicotyledoneae
Life cycle of angiosperms
               Feature of plant
Vascular tissue    have
support            Turgid or woody
sporophyte         all
gametophyte        Minimize to flower
Stem root leave    have
Water absorption   root
Reproduction       Pollen by wind or insect
dispersal          Water wind animals mechanic
Summary of plant kingdom
                                   plant kingdom

                             flowering plants
                          non-                                    flowering plants

         plants without seeds                 plants with seeds    angiosperms

plant body does           plant body has        gynosperms
 not have roots,         leaves,stem and
stems and leaves         root or rootlike
                             structure

     algae         no vacsular    with vascular
                     tissues         tissues

                       moss           ferns
                   (bryophytes)
PRESENTED BY:

   TSANG MAN YEE 6B (26)
    YIK WAI TUNG 6B (31)

				
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posted:9/17/2012
language:English
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