2. 2006-2007 Kingdom Bacteria Kingdom Archaeabacteria Domaine Eukaryote Common ancestor Kingdom: Plants Photosynthetic Eukaryotes

3. Plants General characteristics eukaryotes autotrophs, photosynthetic cell wall cellulose not mobile

4. Transition from water to land Challenges to overcome Water conservation Reproduction without water Internal Transport Support

5. Preventing water loss Cuticle - waxy layer Lipids do not dissolve in water the cuticle creates a barrier that helps prevent the water in the plant’s tissues from evaporating into the atmosphere

6. Plant Diversity Mosses no water transport system (pipes) Ferns water transport, no seeds Conifers pollen & seeds Flowering plants flowers & fruit seed plants water transport system colonization of land

7. Overcoming challenges = Adaptations Symbiosis Tissues Roots/stems/leaves Reproduction Horomones Seeds!

8. Symbiosis Mutualistic associations played a key role in the initial occupation of organisms on land Mycorrihzae (fungi + plant) First plants = no roots Fungi absorbed minerals from rocks Plants now have access to minerals Fungi get free food Commensalism Parasitic

9. Plant Tissue All vascular plants have tissues 3 types Dermal tissue: covers plant’s entire body; serves to protect Ground tissue: performs photosynthesis, stores water and carbohydrates, surrounds and supports the transport tissues Vascular tissue: conducts water, minerals, nutrients and carbohydrates made by photosynthesis

10. Vascular Tissue (vascular bundles) Function – transport Composed of xylem and phloem Xylem: made of dead cells; transports water and minerals from the roots up to the leaves Phloem: transports nutrients and carbohydrates to other parts of the plant

11. Roots Anchor plant in place Absorb water/dissolved minerals from environment Store excess food Root hairs Increase absorptive surface area

12. Leaves Composed of mesophyll tissue and veins (vascular tissue in bundles) Leaves vary greatly in size and shape Function of leaves Photosythesis/energy production Gas exchange transpiration

14. Leaf – external anatomy

15. Leaf – internal anatomy Main organs of photosynthesis in plants Vein Mesophyll Stoma Guard Cells Xylem & Phloem Cuticle Epidermis

16. Leaf Structures Cuticle – waxy covering; prevents water loss through evaporation Mesophyll – majority of leaf; contains vascular tissue; photosynthesis Palisade Spongy

17. Stomata (stoma) – tiny openings on underside of leaf; gas exchange Guard cells – control opening and closing of stomata

18. Leaves and Transpiration Transpiration – water loss through evaporation

19. Stems (shoots) Function – support & house vascular tissue Above ground Main axis of plant Structural adaptation allow plants to overcome obstacle of gravity Connection between roots and leaves

20. XIII. Reproduction Seedless Spores Dependent on water for reproduction Seed bearing Seeds Not dependent on water for reproduction

21. Interdependence within plants Plant systems are dependent on each other If one fails, the rest will fail Roots depend on sugars synthesized by photosynthetic leaves Stems depend on water/minerals absorbed from soil by roots & sugars synthesized by leaves Leaves depend on water/minerals absorbed by roots & support/transport of stem