1. Providers of the Planet
The Plant Kingdom
Providers of the Planet

2. Why study/preserve plants?
So you can:
Breathe  plants process CO2 and give off O2
Eat  all food was made because of plants
Use energy  Ancient plants formed coal
Have raw materials  cotton to lumber
Create new medicines/drugs  non-stop research
Save money  on home heating and cooling
Impress your girlfriend  they like roses 
Have nice landscaping  impress neighbors and increase property values!
Slow/stop/reverse global warming  process CO2
Be a good steward of the environment!

3. Challenges of Life on Land
Obtaining resources from two places at once
Staying “afloat” in air
Maintaining moisture
Reproducing

4. Obtaining Resources From Two Places at Once
Resources required for photosynthetic plant are found in air and soil
Light and CO2 found above ground
Water and minerals found below ground.
Adaptation – Vascular System

5. Staying “Afloat” in Air
Air does not provide support to plants
Plants stand upright because they contain strong and rigid tissue
Adaptation – Lignin: chemical that hardens the plants’cell walls
Lignin is the main component of wood

6. Maintaining Moisture
Most plants are exposed to dry air, but cellular processes must still take place in an aqueous environment
Adaptation – Cuticle: waxy surface that coats the leaves, helping the plant body retain water
Adaptation – Stomata: microscopic pores that allow for gas exchange
Cuticle slows down the gas exchange of CO2 and O2 between the surrounding air and the inside of leaves

7. Reproducing on Land
Plants must keep their gametes and developing offspring from drying out in the air
Plants must have some means for dispersal other than water current
Adaptation – Production of gametes in protective cells
sperm travel within pollen
embryos are eventually dispersed as seeds, enclosed in protective coats

8. Adaptations:
1. Some plants developed Vascular Tissues
Vascular tissues - system of tubes to move water and nutrients (plants have leaves, stems, and roots

9. Adaptations:
2. Cuticle - surface of plant covered with this waxy layer to reduce water loss
3. Spores - more effective way to reproduce

10. Continuing adaptations
Thorns, poison, bad taste, etc.  ward off predators
Woody tissue  support
Seeds  protected/distributed in fruit

11. Bryophytes Non–vascular plants Examples Small size mosses
Require H2O for sexual reproduction
Examples
mosses
liverworts
hornworts
Water and nutrients transported by osmosis and diffusion – can only move material short distances
Larger gametophyte (dominant generation)

12. Teraphytes Seedless Vascular Plants Water needed for fertilization
Drought–resistant spores
Examples
Ferns
club Mosses
horsetails
Vascular system allows them to grow larger
Larger Sporophyte

13. Gymnosperms Gymnosperms (+ seeds) Seeds Wind pollination
Gymnos = naked
Sperma = seed
Wind pollination
Diploid generation
Examples
conifers
cycads
ginkgo
gnetophytes
Seeds protect plant, provide nutrients, permit them to survive long periods of unfavorable conditions, allow for dispersal far from parent plant.
Greatly Reduced Gametophytes
Male gametophyte = pollen
Female gametophyte = form with the seed

14. Gymnosperms
The tallest living plants are the redwoods of California and Oregon
The oldest trees in the world are the bristlecone pines. Some are ~5,000 years old!
Seeds protect plant, provide nutrients, permit them to survive long periods of unfavorable conditions, allow for dispersal far from parent plant.
Greatly Reduced Gametophytes
Male gametophyte = pollen
Female gametophyte = form with the seed

15. Angiosperms Flowers Fruits Endosperm Examples roses apple trees
Angeion = case
Sperma = seed
Endosperm
Examples
roses
apple trees
corn
tomatoes
Most recent group of plants to evolve. Most successful
Flowers promote pollination and fertilization. Bright colors and strong scents attract pollinators
Fruits main function is to promote seed dispersal

16. Evolution of Plants Bryophyte Seedless Seeded Pterophyte Gymnosperm
Angiosperm
Plant Kingdom
Non-vascular Plants
Tracheophyte

17. Other ways to classify plants
Size – taller plants need vascular tissue
Woodiness
Woody plants (trees, shrubs, vines)
Herbaceous plants (flowers, grasses)
Reproduction (seeds or no seeds, fruit vs. cones)
Life span
Annual  one year life span (petunia, impatiens)
Biennial  two year life span (hollyhock)
Perennial  live many years (trees, lilies, roses)