NONVASCULAR

1
NONVASCULAR PLANTS
2

• Bryophytes
• 3 phyla
• most primitive plants
• closer to plants than to algae
• mostly terrestrial
• have alternation of generations
• produce spores
• no vascular tissue so size is less than 1 in
  height
• need H2O to reproduce sexually (sperm must
  swim to egg)

3

• Phylum Bryophyta
• I. general characteristics
• mosses found in every land environment
• pioneer plants 1st species to inhabit barren
  areas
• create layer of soil on rocks that can support
  other plants
• trigger new biological communities
• help prevent soil erosion

4
General Characteristics contd

• sphagnum (peat moss) peat bogs in Ireland,
  Northern Europe, New England, Northern Asia
• peat is partially decomposed plant matter
• produces acid which slows down decomposition
• sphagnum retains H2O

5
Sphagnum moss
6
Peat moss bog in Norway
7
Bog person
8

• 2. Structures
• rhizoids rootlike structures that hold
  gametophytes to soil
• gametophytes make up carpet of moss, usually
  less than 1 tall
• sporophytes at the top of gametophytes, produce
  spores

9
Gametophytes
10
Sporophytes
11

• 3. Life Cycles
• Sexual
• gametophytes produce gametes in antheridia (male)
  and archegonia (female)
• archegonium produces a single egg by mitosis
• under damp conditions, sperm break out of
  antheridia and swim to archegonia.
• Sperm fertilizes egg at base of the archegonium
  forms diploid zygote.
• Zygote forms an embryo which develops into a
  sporophyte

12
Archegonium
13
Antheridium
14
Sporophyte
15

• Asexual
• moss sporophyte is a thin stalk that grows from
  the end of the gametophyte which provides
  nourishment
• cells at tip of sporophyte form a capsule
• capsule cells undergo meiosis to form identical
  haploid spores (this is called homospory)
• when spores are mature, capsule splits open,
  spores disperse and form new gametophytes

16

• Phylum Hepatophyta
• liverworts (Marchantia)
• grow in moist shady areas
• have thin leaf-like structures arranged along a
  stem-like axis
• thalloid form flat body w/ flat upper lower
  surfaces
• all liverworts lie flat so that leaf-like
  structures may absorb H2O (no vascular tissue or
  roots)
• some species have umbrella-like reproductive
  structures
• 
  
  

17
Marchantia - liverworts
18
(No Transcript)
19

• Phylum Anthocerophyta
• Hornworts
• resemble liverworts in structure and habitat
• like algae, each cell has one large chloroplast
  instead of many small ones

20
Hornwort
21
SEEDLESS VASCULAR PLANTS
22

• Phylum Psilotophyta
• whisk ferns
• have no roots or leaves
• spores are produced at the end of short branches
• thought to resemble early land plants
• epiphytic (grow on other plants but do not harm
  plant)
• up to 1 tall
• habitat tropical temperate climate as far
  north as S. Carolina

23
Whisk ferns
24

• Phylum Lycophyta
• club moss (ground pine)
• strobilus conelike structure which contains
  sporangia that make spores
• examples
• lycopodium used in Xmas decorations spores
  are use to create special effects. Spores can
  cause life-threatening allergies.
• Selaginella resurrection plant curls up in
  ball during drought. When H2O is added plant
  uncurls turns green in hrs.

25
Lycopodium
26

• Phylum Sphenophyta
• horsetails (Equisetum)
• have jointed stems where photosynthesis occurs
• stems have scale-like leaves contain silica
• spores are produced in conelike structures
• were called scouring rush by European colonists
  were used to scrub pots

27
Horsetails
28
F e r n s
29

• Phylum Pterophyta
• ferns
• appeared 350 million yrs. ago
• range in size from .4 in. to 16 ft. (tree ferns)
• habitats aquatic, temperate, tropical, Arctic,
  or deserts
• Structures
• - rhizome underground stem
• - fiddleheads tightly coiled new leaves (some
  are edible)
• - fronds mature fern leaves

30
Fern Life Cycle 1. most ferns are homosporous (
produce identical spores) 2. fern sporophyte
grows from the gametophyte 3. sporophyte is
dominant generation 4. gametophytes are tiny
flat plants held to the soil by rhizoids 5.
antheridia archegonia form on under surface of
gametophyte 6. during wet periods, sperm is
released from antheridia and swims to archegonia
fuses w/ egg to form zygote
31
Fern sporophyte
32
Fern gametophyte
33
Fern cycle contd

• 7. zygote grows into embryo which becomes a
  young fern
• 8. sporangia grow on underside on fronds
• some ferns produce clustered sporangia called
  sori
• 9. sporangial cells undergo meiosis to make
  haploid spores
• 10. spores are carried on air currents, land on
  the ground, and then grow into new gametophytes

34
Fern with sori