Chapter 29

1. Plant Tissues Chapter 29

2. Volcano is located in southwestern Washington state In 1980 it erupted, blowing 500 million metric tons of rock and ash outward Ash and lava devastated about 40,500 acres of what had been forest Mount Saint Helens Eruption

3. Plants moved into the empty habitat almost immediately Fireweed and blackberry were early colonists In less than ten years, willow and alders were on the scene Recovery

4. The angiosperms are seed-bearing vascular plants In terms of distribution and diversity, they are the most successful plants on Earth The structure and function of this plant group help explain its success Success of the Angiosperms

5. Shoots • Produce food by photosynthesis • Carry out reproductive functions • Roots • Anchor the plant • Penetrate the soil and absorb water and dissolved minerals • Store food Shoots and Roots

6. Shoot Apical Meristem primary meristems active epidermis, ground tissues, primary vascular tissues forming epidermis, ground tissues, primary vascular tissues forming primary meristems active Root Apical Meristem Fig. 29-3a, p.494

7. a The cellular descendants of apical meristems divide, grow, and differentiate. They form three primary meristems, the activity of which lengthens shoots and roots: Protoderm epidermis Ground meristem ground tissues Procambium primary vascular tissues Fig. 29-3a1, p.494

8. vascular cambium cork cambium thickening Lateral Meristems Fig. 29-3b, p.494

9. Angiosperm Body Plan EPIDERMIS • Ground tissue system • Vascular tissue system • Dermal tissue system VASCULAR TISSUES GROUND TISSUES SHOOT SYSTEM ROOT SYSTEM Fig. 29-2, p.494

10. Monocots and Dicots: 1 cotyledon 2 cotyledons 4 or 5 floral parts 3 floral parts Netlike veins Parallel veins 3 pores 1 pore Vascular bundles in ring Vascular bundles dispersed

11. Made up of only one type of cell Parenchyma Collenchyma Sclerenchyma Simple Tissues

12. Most of a plant’s soft primary growth Pliable, thin walled, many sided cells Cells remain alive at maturity and retain capacity to divide Mesophyll is a type that contains chloroplasts Parenchyma: A Simple Tissue

13. fibers of sclerenchyma vessel of xylem parenchyma phloem simple and complex tissues inside the stem stem epidermis Fig. 29-6, p.496

14. Specialized for support for primary tissues Makes stems strong but pliable Cells are elongated Walls thickened with pectin Alive at maturity Collenchyma: A Simple Tissue

15. Supports mature plant parts • Protects many seeds • Thick, lignified walls • Dead at maturity • Two types: • Fibers: Long, tapered cells • Sclereids: Stubbier cells Collenchyma: A Simple Tissue

16. collenchyma parenchyma lignified secondary wall Fig. 29-7, p.496

17. Composed of a mix of cell types Xylem Phloem Epidermis Complex Tissues

18. Xylem • Conducts water and dissolved minerals • Conducting cells are dead and hollow at maturity vessel member tracheids

19. sieve plate of sieve tube cell one cell’s wall pit in wall companion cell a b c Fig. 29-8, p.497

20. Transports sugars Main conducting cells are sieve-tube members Companion cells assist in the loading of sugars Phloem: A Complex Vascular Tissue sieve plate sieve-tube member companion cell

21. Covers and protects plant surfaces Secretes a waxy, waterproof cuticle In plants with secondary growth, periderm replaces epidermis Epidermis: A Complex Plant Tissue

22. photosynthetic cell leaf surface cuticle epidermal cell Fig. 29-9, p.497

23. Regions where cell divisions produce plant growth • Apical meristems • Lengthen stems and roots • Responsible for primary growth • Lateral meristems • Increase width of stems • Responsible for secondary growth Meristems

24. activity at meristems Apical Meristems new cells elongate and start to differentiate into primary tissues Shoot apical meristem new cells elongate and start to differentiate into primary tissues Root apical meristem activity at meristems

25. immature leaf shoot apical meristem lateral bud forming cortex vascular tissues pith Fig. 29-10a2, p.498

26. immature leaf shoot apical meristem descendant meristems (orange) b Sketch of the shoot tip, corresponding to (a) Fig. 29-10b, p.498

27. Protoderm Ground meristem Procambium Tissue Differentiation Epidermis Ground tissue Primary vascular tissue

28. Increase girth of older roots and stems Cylindrical arrays of cells Lateral Meristems vascular cambium cork cambium thickening Figure 29.20.a Page 504

29. immature leaf Shoot Development shoot apical meristem procambium protoderm procambium ground meristem epidermis cortex primary phloem procambium Figure 29.10  Page 498 primary xylem pith

30. immature leaf shoot apical meristem descendant meristems (orange) cortex primary phloem primary xylem pith Stepped Art Fig. 29-10b-d, p.498

31. Vascular cambium Cork cambium Tissue Differentiation Secondary vascular tissue Periderm

32. Outermost layer is epidermis Cortex lies beneath epidermis Ring of vascular bundles separates the cortex from the pith The pith lies in the center of the stem Internal Structure of a Dicot Stem Figure 29.11.a Page 499

33. Internal Structure of a Monocot Stem • The vascular bundles are distributed throughout the ground tissue • No division of ground tissue into cortex and pith Figure 29.11.b Page 499

34. vessel in xylem meristem cell epidermis cortex vascular bundle pith sieve tube in phloem companion cell in phloem Fig. 29-11a, p.499

35. air space vessel in xylem collenchyma sheath epidermis vascular bundle pith sieve tube in phloem companion cell in phloem Fig. 29-11b, p.499

36. Common Leaf Forms DICOT MONOCOT petiole axillary bud blade node sheath blade node Figure 29.12.a,b Page 500

37. Leaves are usually thin • High surface area-to-volume ratio • Promotes diffusion of carbon dioxide in, oxygen out • Leaves are arranged to capture sunlight • Are held perpendicular to rays of sun • Arranged so they don’t shade one another Adapted for Photosynthesis

38. POPLAR (Populus) OAK (Quercus) MAPLE (Acer) leaflet RED BUCKEYE (Aesculus) BLACK LOCUST (Robina) HONEY LOCUST (Gleditsia) Fig. 29-12c,d, p.500

39. Leaf Structure UPPER EPIDERMIS cuticle PALISADE MESOPHYLL xylem SPONGY MESOPHYLL phloem LOWER EPIDERMIS one stoma CO2 O2 Figure 29.14.b Page 501

40. Leaf Vein (one vascular bundle) leaf blade cuticle leaf vein Upper Epidermis Palisade Mesophyll stem xylem Spongy Mesophyll Water, dissolved mineral ions from roots and stems move into leaf vein (blue arrow) Lower Epidermis 50m phloem cuticle-coated cell of lower epidermis Photosynthetic products (pink arrow) enter vein, will be transported throughout plant body one stoma (opening across epidermia) Oxygen and water vapor diffuse out of leaf at stomata. Carbon dioxide in outside air enters leaf at stomata. Fig. 29-14, p.501

41. A type of parenchyma tissue • Cells have chloroplasts • Two layers in dicots • Palisade mesophyll • Spongy mesophyll Mesophyll:Photosynthetic Tissue

42. Xylem and phloem; often strengthened with fibers In dicots, veins are netlike In monocots, they are parallel Leaf Veins: Vascular Bundles

43. Leaf Veins Fig. 29-15a, p.501

44. Leaf Veins Fig. 29-15b, p.501

45. Root Systems Fibrous root system of a grass plant Taproot system of a California poppy Figure 29.19 Page 503

46. Root cap covers tip Apical meristem produces the cap Cell divisions at the apical meristem cause the root to lengthen Farther up, cells differentiate and mature Root Structure Figure 29.16.a Page 502

47. Outermost layer is epidermis Root cortex is beneath the epidermis Endodermis, then pericycle surround the vascular cylinder In some plants, there is a central pith Internal Structure of a Root

48. pith cortex epidermis VASCULAR CYLINDER primary xylem primary phloem Fig. 29-17, p.503

49. Ring of cells surrounds vascular cylinder Cell walls are waterproof Water can only enter vascular cylinder by moving through endodermal cells Allows plant to control inward flow Function of Endodermis

50. Both increase the surface area of a root system Root hairs are tiny extensions of epidermal cells Lateral roots arise from the pericycle and must push through the cortex and epidermis to reach the soil Root Hairs and Lateral Roots new lateral root