Plant Diversity I

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Plant Diversity I
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Plant Kingdom is Monophyletic one common ancestor

• Primary Products main metabolic pathways
• Amino acid synthesis
• Production of cellulose
• Products needed for growth and development

• Secondary Products products for survival but not
  central
• metabolic needs
• Protection
• Waxes of cuticle
• Lignin hardens cell walls of woody tissue
• Sporopollenin polymer resistant to harsh
  environments

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EmbryophytesKey adaptation for success on land
Gametangia organ of sterile cells protecting
gametes egg is fertilized in female gametangia

• Alternating
• Generations
• Gametophyte (1n)
• Sporophyte (2n)

Heteromorphic
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Plant Phylogeny
Gametangia/sporopollenin
Flowering Plants
Seed Develops
Vascular Tissues
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Classification
Division Phylum
Charophytes green algae closely related to
plants

• Homologies
• Chloroplasts chlorophyll b and beta-carotene
  match
• Biochemical cellulose, peroxisomes
• Mitosis.Meiosis similar in both.
• Sperm ultrastructure
• Genetic Relationship nuclear genes and
  ribosomal RNA

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Delayed Mitosis
Charophytes modern ones do not have alterations
of generations. Most release gametes in water
for fertilization to take place. Clues looked at
in Coleochaete Retains the eggs, after
fertilization
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Bryophytes

• First moved to land (gametangia development)
• Male sperm antheridium
• Female egg archegonium
• Need water to reproduce
• No vascular tissue to carry water
• Lack Lignin fortified tissue for support
• Gametophyte prominent generation

• Division Bryophyta mosses
• Division Hepatophyta Liverworts
• Division Anthocerphyta Hornworts

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Origin of Vascular Plants

• Two Systems
• Subterranean Root System
• Aerial Shoot System

• Two Conducting Tissues
• Xylem tube shape cells carry water and mineral
  from roots
• Phloem living tissue w/ food conducting cells,
  distribute
• sugars, a.a, organic nutrients.

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Seedless Vascular Plants

• Sporophyte in dominant, larger, and more complex.
• Homosporous plant producing single type of
  spore
• Heterosporous produces two type of spores (water
  ferns only)
• Megaspore develop into female gametophytes
  bearing
• archegonia
• Microspores develop into male gametophytes with
• antheridia