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0. Seed-bearing Plants fall into two major categories. Angiosperms. Gymnosperms. 0. Seed-bearing Vascular Plants fall into two major categories. Gymnosperms – seeds naked on surface of cone scale Angiosperms – seeds enclosed in a ripened ovary and flowers are produced. - PowerPoint PPT Presentation
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Seed-bearing Plants fall into two major categories
Gymnosperms
Angiosperms
Seed-bearing Vascular Plants fall into two major categories
• Gymnosperms – seeds naked on surface of cone scale
• Angiosperms – seeds enclosed in a ripened ovary and flowers are produced
GYMNOSPERM CHARACTERISTICS
• From Greek words gymnos (naked) and sperma (seed)
• Both Male and Female cones
Land Plants
Bryophytes Pteridophytes
Bryophytes
Pteridophyte
Gymnosperms
Angiosperms
Flowers and Fruits
Vascular Tissue
Seeds
Seed-bearing plants also produce pollen
Five Living Seed Plant Phyla
• Cycadophyta
• Ginkgophyta
• Pinophyta or Coniferophyta
• Gnetophyta
• Anthophyta
Gymnosperms
Angiosperms
Living Gymnosperm Phyla
Cycadophyta - Cycads
Gnetophyta - Gnetophytes
Ginkgophyta - Ginkgos
Conifers - Pinophyta or Coniferophyta
Conifers – the most conspicuous and common gymnosperms
Conifers
About 70 genera with about 630 species
Conifers
• Conifers are well represented in the fossil record
Sequoia affinis
Conifers are of great ecological importance
• Conifers are the dominant members of the vast Boreal forests (Taiga)
Conifers are of great ecological importance
• Conifers are very important members of many types of ecosystems
Conifers are of great economic importance
• Edible Seeds• Crates, Boxes,
Matchsticks, Furniture
• Telephone Poles• Turpentine and
Rosin (Resin)• Fuel (Pitch)• Pulpwood• Ornamentals• Pharmaceuticals
(Taxol)
There are Seven Living Families of
Conifers
Pinaceae - Pine familyAraucariaceae - Araucaria familyPodocarpaceae - Yellow-wood familySciadopityaceae - Umbrella-pine familyCupressaceae - Cypress familyCephalotaxaceae - Plum-yew familyTaxaceae - Yew family
Five of the Most Familiar Groups of Conifers
Norfolk Island Pines
Junipers and Cedars
Yews
Sequoias and Redwoods
Pines, Firs, Spruces
The Largest, Tallest, and the Oldest Plants
are Conifers.All found in California• Giant Sequoias of the
California Sierras are the largest
• Coastal Redwoods are the tallest
• Bristlecone pines of the California White Mountains are the oldest
Pines - genus Pinus of the family Pinaceae
• Most familiar of all conifers
• About 90 species
Vegetative Characters of Pine
Pine Stems
• Extensive branching• Christmas tree shape• Very woody
Pine Leaves
• Needles produced in clusters (fascicles) of 1 to 5
Pine – Reproductive Structures
Pines produce pollen and seeds in cones
Pines are MoneciousIndividual plants produce both pollen cones and
seed cones
C
Seed Cone
Pines are MoneciousIndividual plants produce both pollen cones and seed
cones
C
Pollen Cone
Pollen cones produce pollen
C
Pine Pollen• Wind pollination is facilitated by
pollen morphology.
Ovulate or Seed Cones Produce Seeds
C
Young seed cone
Mature seed cone
Cone scale
Conifer Seed reminder
Bald Cypress
Juniper
Giant Sequoia
PineYew (aril)
Conifer Cones
Conifer Leaves
Map of Living and Fossil Members of Taxodiaceae (Redwood Family)
Dawn Redwood Metasequoia glyptostroboides and Coastal Redwood Sequoia sempervirens
Cycadophytathe Cycads
Cycads Appeared on Earth 250 MYA
• Greatest abundance and diversity during the Jurassic
• Declined sharply during the Cretaceous radiation of the angiosperms.
Cycad seeds are toxic to humans• Cyanobacteria in roots of cycads• Flying foxes eat neurotoxic cycad seeds• Humans eat the flying foxes• Humans get sick (neurological disorders)
Cycads
MexicanAustralian
African
Only Cycad Native to the US
Zamia integrifolia
Atala Butterfly
Cycads contain cycasin, a toxic secondary plant chemical. Cycads are toxic to humans, dogs and livestock. Cycasin is found in the atala butterfly and other organisms find it distasteful and avoid eating it.
Host Plant for
In Florida
Gymnosperms
Cycads
Ginkgos
Conifers
Bryophytes Pteridophytes
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