FBS 21 (Bryophytes, Angiosperms, Gymnosperms)

• Bryophytes (liverworts, hornworts, mosses)

  1. Unspecialized vascular tissue
  2. No roots (absorptive structures)
  3. Dominant generation gametophyte
  4. Sporophyte attached to gametophyte
  5. Water needed for fertilization
• SEEDLESS VASCULAR PLANTS:

  DIVISION PTERIDOPHYTA

  1. Commonly known as ferns
  2. About 12,000 spp. primarily in the tropics
  3. Ophioglosopsida
  4. Marattiopsida
  5. Felicopsida – the largest group
  6. 145 genera 930 spp., 278 endemic spp
• Ferns and Allies

  Seedless vascular plants include two major groups of plants: the Lycophytes (about 1000 species, including the club mosses and the genera Selaginella and Isoetes), and the ferns and allies, including the horsetails, whisk ferns, and other ferns. These lineages share a number of characteristics. They are the earliest set of lineages to have evolved vascular tissue (xylem and phloem).
• Lycopodiophyta:

  Lycophytes are a division of vascular plants, also known as tracheophytes, which includes several plant families such as club mosses (Lycopodiaceae), spike mosses (Selaginellaceae), and quillworts (Isoetaceae).

  
  

  They are characterized by small, herbaceous plants with simple leaves, often arranged spirally along their stems. Lycophytes reproduce via spores, which are produced in structures called strobili or cones
• Lycophytes: Lycopodiaceae

  (15 genera / 375 species)
• Lycophytes: Isoetaceae

  (1 genus, 150 species)
• Lycophyta:

  1. Selaginellaceae
  2. Isoetaceae
  3. Lycopodiaceae
  4. Equisetaceae
  5. Psilotaceae
  6. Ophioglossaceae
  7. Leptosporangiate ferns (Osmundaceae)
• Leptosporangiate ferns (sporangium wall of 1 cell layer)

  .worldwide distribution, diverse habitats (200 genera / 9000 species)

  Osmundaceae

  • sporangia not arranged in sori
  • heterosporic
  • aquatic
  • sporangia in sporocarps
• Polypodiophyta (Ferns):

  • Ferns are a diverse group of plants characterized by large, compound leaves called fronds, which are typically divided into leaflets known as pinnae.
  • They reproduce via spores, which are produced in structures called sporangia located on the undersides of the fronds in clusters called sori.
  • These spores germinate to form small, heart-shaped gametophytes, which produce sperm and eggs that fuse to form a new sporophyte generation.
• Pteridophytes typically have larger, compound leaves

  known as fronds, which are divided into leaflets called

  pinnae. The leaflets may be further divided into smaller segments called pinnules.
• Polypodiophyta: Polypodiaceae

  • sporangia in sori
  • diverse morphology
  • diverse habitats
• Polypodiophyta: Cyatheaceae

  tree ferns w/ arborescent trunks

  sporangia in sori
• SEED PLANTS:

  • Cycadophyta
  • Ginkgophyta
  • Pinophyta
  • Gnetophyta
• The Seed Plants:

  This neat little package called a seed is an innovative step in plant evolution that helped some plants thrive in terrestrial ecosystems.

  Seeds allowed plant embryos to withstand freezing, desiccation, and ultraviolet light damage in terrestrial environments while providing energy storage (endosperm).
• Gymnosperms are a group of seed- producing plants that are characterized by the absence of a protective covering or enclosure around their seeds. The term "gymnosperm" comes from the Greek words "gymnos," meaning "naked," and "sperma," meaning"seed."

  
  

  Unlike angiosperms (flowering plants), which produce seeds enclosed within a fruit, gymnosperms produce seeds exposed on the surface of specialized structures, such as cones or cones- like structures.
• THE GYMNOSPERM:

  • Gymno = naked, sperm = seed

  • Seeds are develop at the tip or surface of appendage.

  • In the Philippines, we have 4 divisions, 4 classes, four orders, 6 families, 12 genera and 33 species

  • 18% species endemism

  • No exclusive genus
• DIVISION GINKGOPHYTA:

  • Represented by single species Ginkgo biloba known as “Maidenhair tree”

  • Dichotomously veined, fan-shaped leaves, deciduous trees, dioecious

  • Ovules of Maidenhair tree are exposed and occur singly at the tips of fertile branches

  • Sperm cells are flagellated
• DIVISION CYCADOPHYTA:

  • Single class and order, 3 families, 185 species

  • 4 species in single family in the Philippines

  • palmlike leaves that bear no resemblance to leaves of other living gymnosperms

  • Dioecious, pollen and ovules are formed in sporangia that occur in simple cones

  • Sperm cells are flagellated and can reach up to 400 micrometers in diameter
• DIVISION CONIFEROPHYTA:

  • About 550 spp.,

  • 2 classes (Coniferopsida and Taxopsida) each with single order

  • In the Philippines, Coniferopsida is represented by 23 species, 10 genera, and 3 families, while Taxopsida is represented by lone species Taxus sumatrana.

  • w/ non motile sperm cells
• Division Coniferophyta:

  • commonly known as conifers, refers to a division within the plant kingdom
  • characterized by cone-bearing trees and shrubs.
  • These plants typically have needle-like or scale-like leaves and produce seeds enclosed in cones.
  • Conifers are mostly evergreen and include familiar species such as pine, spruce, fir, and cedar.
  • Monoecious: Plants produce both male and female strobili on the same plant.
  • Typically wind pollinated
• Gymnosperms

  Taxaceae

  • linear leaves
  • usually dioecious
  • solitary ovules
  • fleshy, brightly
  • colored aril
  • Taxus = source of taxol
  • 5 genera / 20 species
  • Hemisphere temperate - tropical
• Gynosperms

  Cupressaceae s.l. (s.l. = sensu lato = “in the broad sense” (including Taxodiaceae)

  • scale-like or linear leaves (persistent on branchlets, alternate, opposite or whorled)
  • usually monoecious sometimes dioecious in Juniperus
  • ovulate cones (cone scales peltate or flat seeds, 1-20 per scale, 2 lateral wings)
  • tallest trees Sequoia
  • most massive trees Sequoiadendron
  • Metasequoia = “living fossil” described from fossils in 1941, discovered alive in China in 1944
  • 29 genera / 120 species
  • temperate - subtropical, worldwide
• Gymnosperm: Cuppressaceae s.l.

  Xanthocyparis vietnamensis (Discovered in 1999 in Vietnam, Published in 2002, Shares morphological features with Chamaecyparis nootkatensis)
• Gymnosperm: Pinaceae

  • linear leaves (abcising from branchlets, alternate or fascicled)
  • monoecious
  • ovulate cones
  • cone scales flat
  • seeds 2 per scale
  • terminal wing
  • longest lived trees Pinus longaeva (bristlecone pine)
  • 10 genera/ 220 species
  • north temperate
• Division Gnetophyta: Ephedra

  • 50 desert species
  • jointed green stems
  • source of ephedrine (blood vessel constrictant)
• Division Gnetophyta: Welwitschia

  1. 1 species, Namibian desert
  2. two persistent leaves only
• Division Gnetophyta: Gnetum

  • 40 tropical species
  • lianas & trees
  • leaves with reticulate venation
• DIVISION GNETOPHYTA

  • includes 3 genera and 71 species that are grouped into one class
  • the only gymnosperms that possess vessels, and undergo double fertilization
  • Philippine gnetophytes is represented with 4 species under only one genus, Gnetum
  • Combine gymosperm and angiosperm characters
  • * vessels in wood
  • * flowerlike structures
  • * double fertilization
  • * seeds not enclosed in a carpel