Chapter 35 - Plant Structure

5,411 views
4,595 views

Published on

Published in: Technology, Education
0 Comments
9 Likes
Statistics
Notes
  • Be the first to comment

No Downloads
Views
Total views
5,411
On SlideShare
0
From Embeds
0
Number of Embeds
184
Actions
Shares
0
Downloads
273
Comments
0
Likes
9
Embeds 0
No embeds

No notes for slide

Chapter 35 - Plant Structure

  1. 1. AP Biology 2006-2007 Plant Anatomy
  2. 2. AP Biology Basic plant anatomy 1  root  root tip  root hairs
  3. 3. AP Biology Plant Body Hierarchy  Tissue  Cells with a common function  Organ  3 basic organs  Roots  Stems  Leaves
  4. 4. AP Biology Roots  Roots anchor plant in soil, absorb minerals & water, & store food  fibrous roots (1)  mat of thin roots that spread out  monocots  tap roots (2)  1 large vertical root  also produces many small lateral, or branch roots  dicots  root hairs (3)  increase absorptive surface area 2 1 3
  5. 5. AP Biology Basic plant anatomy 2  root  root tip  root hairs  shoot (stem)  nodes  internodes  buds  terminal or apical buds  axillary buds  flower buds & flowers
  6. 6. AP Biology Modified shoots stolons (strawberries) rhizome (ginger) tuber (potato) bulb (onion)
  7. 7. AP Biology Basic plant anatomy 3  root  root tip  root hairs  shoot (stem)  nodes  internodes  buds  terminal or apical buds  axillary buds  flower buds & flowers  leaves  mesophyll tissue  veins (vascular bundles)
  8. 8. AP Biology Leaves  Function of leaves  photosynthesis  energy production  CHO production  gas exchange  transpiration simple vs. compound
  9. 9. AP Biology succulent leaves Modified leaves tendrils (peas) spines (cacti) colored leaves (poinsetta)
  10. 10. AP Biology
  11. 11. AP Biology  Both systems depend on the other  roots depend on sugars produced by photosynthetic leaves  shoots depend on water & minerals absorbed from the soil by roots Interdependent systems water & minerals sugars
  12. 12. AP Biology Plant TISSUES  Dermal  epidermis (“skin” of plant)  single layer of tightly packed cells that covers & protects plant  Ground  bulk of plant tissue  photosynthetic mesophyll, storage  Vascular  transport system in shoots & roots  xylem & phloem
  13. 13. AP Biology Plant CELL types in plant tissues  Parenchyma  “typical” plant cells = least specialized  photosynthetic cells, storage cells  tissue of leaves, stem, fruit, storage roots  Collenchyma  unevenly thickened primary walls  support  Sclerenchyma  very thick, “woody” secondary walls  support  rigid cells that can’t elongate  dead at functional maturity If I’d only had triplets!
  14. 14. AP Biology Parenchyma  Parenchyma cells are unspecialized, thin, flexible & carry out many metabolic functions  all other cell types in plants develop from parenchyma
  15. 15. AP Biology Collenchyma  Collenchyma cells have thicker primary walls & provide support  help support without restraining growth  remain alive in maturity the strings in celery stalks are collenchyma
  16. 16. AP Biology Sclerenchyma  Thick, rigid cell wall  lignin (wood)  cannot elongate  mostly dead at maturity  Cells for support  xylem vessels  xylem tracheids  fibers  rope fibers  sclereids  nutshells  seed coats  grittiness in pears
  17. 17. AP Biologytracheids vessel elements Vascular tissue Aaaah… Structure–Function again! vessel element dead cells  Xylem  move water & minerals up from roots  dead cells at functional maturity  only cell walls remain  need empty pipes to efficiently move H2O  transpirational pull
  18. 18. AP Biology Phloem: food-conducting cells  carry sugars & nutrients throughout plant sieve tube companion cell living cells plasmodesmata sieve plate
  19. 19. AP Biology Phloem: food-conducting cells  sieve tube elements & companion cells
  20. 20. AP Biology Phloem  Living cells at functional maturity  cell membrane, cytoplasm  control of diffusion  lose their nucleus, ribosomes & vacuole  more room for specialized transport of liquid food (sucrose)  Cells  sieve tubes  sieve plates — end walls — have pores to facilitate flow of fluid between cells  companion cells  nucleated cells connected to the sieve-tube  help sieve tubes Aaaah… Structure–Function again!
  21. 21. AP Biology Vascular tissue in stems dicot trees & shrubs monocot grasses & lilies collect annual rings
  22. 22. AP Biology Vascular tissue in roots: dicot xylemphloem
  23. 23. AP Biology xylem phloem Vascular tissue in roots: monocot
  24. 24. AP Biology Putting it all together  Obtaining raw materials  sunlight  leaves = solar collectors  CO2  stomates = gas exchange  H2O  uptake from roots  nutrients  uptake from roots
  25. 25. AP Biology Plant Growth  Apical meristem  Growth in length  Primary  Lateral meristem  Growth in diameter  Secondary
  26. 26. AP Biology
  27. 27. AP Biology  Woody plants grow in height from tip  primary growth  apical meristem  Woody plants grow in diameter from sides  secondary growth  lateral meristems  vascular cambium  makes 2° phloem & 2° xylem  cork cambium  makes bark Growth in woody plants Primary phloem Primary xylemSecondary phloem Secondary xylem Annual growth layers Lateral meristems Primary xylem Primary phloem Bark Epidermis
  28. 28. AP Biology Primary growth of roots  Root cap  Protects root as it grows  Cell division (mitosis)  Cells small  Cell elongation  Cell differentiation  Cells mature into final cell types
  29. 29. AP Biology Primary growth of stems  Shoot apical meristem  Dividing cells at shoot tip  Develop from axillary bud on stem’s surface
  30. 30. AP Biology Secondary plant growth: vascular cambium  Adds secondary xylem & phloem  Thickens roots & stems  Heartwood  Close to center  Does not transport water  Sapwood  Transport xylem sap  Outer layers
  31. 31. AP Biology Secondary plant growth: cork cambium  Periderm  Cork cambium & tissues  Produces thick covering  Protects from water loss  Phelloderm  Thin layer of parenchyma  Secondary tissue  Exterior of cork cambium  Suberin - waxy

×