3. Roots, Stems and Leaves  Roots  Absorption  Root hairs increase surface area  Mycorrhizae are symbiotic fungi that help plants absorb nutrients.  Types  Fibrous- shallow, increased surface area(monocots)  Tap – deep, used for storage(dicots)  Adventitious – climbing roots, above ground

4. Stems  Parts  Nodes  Internodes  Auxillary buds  Terminal buds – apical dominance  Modified Stems  Stolons – above ground horizontal (strawberries)  Rhizomes – below ground horizontal (tubers)

5. Modified Shoots

6. Rhizomes

7. Stolons of Strawberries

8. Underground Stem

9. Tubers

10. Root Hair Radish

13. Leaves

14. Plant Tissues  Dermal – epidermis  Protection  Layer of tightly packed cells  Waxy cuticle prevent water loss  Vascular  Xylem – Tracheids and vessel elements  Phloem – sieve tube members and companion cells.  Ground  Between dermal and vascular tissue  Pith and Cortex  Function – photosynthetic, storage and support.  Cortex of a dicot stem- both storage and support(large trees)

16. Primary and Secondary Walls

17. Types of Plant Tissues

18. Parenchymal  Structure  No primary wall  Thin flexible  Least specialized  Large vacuoles  Ground tissue is primarily parenchymal.

19. Parenchymal Tissue

20. Collenchymal  Structure  Thicker primary walls than parenchymal cells.  Primary walls have uneven thickness  No secondary wall.  Found in young growing herbaceous plant stem.  Function  To provide flexible support for growing plants

21. Collencymal Tissue

22. Sclerencymal Tissue  Structure  Thick secondary wall  Much more rigid than collencymal tissue.  Dead at maturity and cannot elongate  Deposited in tissues of the plant that are not growing.  Found in bark, wood, nut shells, hemp  Makes pears gritty.  Two types of cells – fiber cells and sclereids.  Function  Support

23. Fiber Cells

24. Sclereids

26. Stem Structure

28. Leaf Anatomy

30. Behold The Stomata!

32. Leaf Anatomy

33. Root Structure

34. Monocot Root

35. Dicot Root

36. Plant Growth

37.  Plants exhibit indeterminate growth  Grows throughout its entire lifetime.  Annuals, biannuals, perenials Growth Tissue is called Meristematic tissue.  Apical Meristem  Primary growth - vertical growth  Tips of roots and shoots  Lateral Meristem  Secondary growth - horizontal growth  Rings in a tree can determine its age.  Cambiums  Vascular Cambium – xylem and phloem  Cork Cambium – cork and bark  Pericycle –roots and root hairs.

38. Primary Root Growth

39. Beware of The Primordial Leaf

40. Secondary Growth  Most Monocots don NOT exhibet secondary growth.  Vascular Cambium gives rise new vascular tissue  Xylem towards the center of the stem.  Older xylem is towards the center of a tree.  Older xylem is dead  Fills with sap and provides support  Phloem towards the exterior.  Older phloem is closer to the bark.

41. Cork Cambium  Produces cork to exterior  Primary epidermis splits and falls off  Cork cambium cells secrete a waxy substance called suberin and die.  Cork and cork cambium provide protection and are called the periderm.  Cork cambium does not change diameter.  Old phloem and bark slough off.  Lenitcles are openings in the cork cambium.

42. Secondary Growth