Plant tissues

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Plant tissues

  1. 1. By iTutor.com T- 1-855-694-8886Email- info@iTutor.com
  2. 2. TissuesA group of closely associated cells that performrelated functions and are similar in structure.
  3. 3. Plant Tissues Tissues in plants that divide throughout their life. Plant tissues can be classified as:  Growing or Meristematic tissue  Permanent tissue Permanent tissue Meristematic tissue
  4. 4. Meristematic tissues The growth of plants occurs in certain specific regions.  This is because the dividing tissue,  Known as meristematic tissue Composed of actively dividing ceIIs, responsible for the production of ceIIs. Capacity for division is restricted to certain parts of the plant body called meristems  Which are active throughout the life of the plant body.
  5. 5. Meristematic tissues
  6. 6. Meristematic tissuesKinds of meristems:• Apical meristems – found at the tip of stems & roots• Lateral meristems – a.k.a. cambia - found along the sides of roots & stems - increase width or diameter of stems & roots - types: 1. vascular cambium 2. cork cambium• Intercallary meristems – found at the bases of young leaves & internodes - responsible for further lengthening of stems & leaves
  7. 7. Permanent tissues Tissues that attained their mature form and perform pacific functions. They stop dividing Types: • Simple permanent tissues • Complex permanent tissues
  8. 8. Dermal / surface tissue Simple permanent tissues - consist only of one kind of cellsA. Dermal / surface tissue - external tissues - forms protective covering of the plant body a. Epidermis b. Periderm
  9. 9. Permanent tissues• Epidermis - the outermost layer of the primary plant body - covers the leaves, floral parts, fruits, seeds, tems and roots - generally only one layer thick with cuticle - composed mostly of unspecialized cells, either parenchyma and/or sclerenchyma - contains trichomes, stomata, buIIiform ceIIs (in grasses)
  10. 10. Structure of epidermis
  11. 11. Stomata• Stomata - pores for gas exchange - present on one or both surfaces of Leaves.
  12. 12. Cuticle Cuticle – Lines the outer waII of the epidermal ceIIs - made up of waxy material that protects plants from desiccationCuticle Layer of the leaf
  13. 13. TrichomesTrichomes – outgrowths of epidermal ceIIs
  14. 14. Periderm (Bark)• Periderm (Bark) is the outermost layer of stems and roots of woody plants such as trees.
  15. 15. Ground tissues1. Parenchyma - are the general purpose ceIIs of plants - cells are rounded in shape & have uniformly thin walls found in all parts of the plants. - living at maturity, have large vacuoles - location Ieaf, stem (pith), roots, fruitsFunctions:*basic metabolic function (respiration, photosynthesis (chIorenchyma in Leaf) & protein synthesis)*storage (potatoes, fruits, & seeds)*wound healing and regeneration
  16. 16. Parenchyma
  17. 17. ChIorenchyma2. ChIorenchyma - A specialized parenchyma tissue found in the green parts of the shoot and performs photosynthesis. - differentiate from parenchyma cells & are alive at maturityFunctions: Support & elasticity (stem surfaces & along leaf veins) Segeneration
  18. 18. ScIerenchyma3. ScIerenchyma  sclerenchyma cells which are non-living and lack protoplasts at maturity  Have thick, lignified secondary walls  Provide strength and support in parts that have ceased elongating or matureTypes: 1. ScIereids or stone cells 2. Fibers
  19. 19. Complex Permanent TissuesVascular TissuesSpecialized for long-distance transport of water and dissolved substances.Contain transfer ceIIs, fibers in addition to parenchyma and conducting ceIIs.Location, the veins in IeavesTypes: 1. Xylem 2. phloem
  20. 20. XylemXylem GW xyIos w/c means “wood” transports water and dissolved nutrients from the roots to aII parts of a plant.  Direction of transport is upward.There ate two types• Primary xylem – differentiates from procambium in the apical meristem & occurs throughout the primary plant body.• Secondary xylem – differentiates from vascular cambium & is commonly called wood.
  21. 21. Xylem
  22. 22. Xylem• Xylary elements – the conducting cells in xylem - 2 kinds of xylary elements: – tracheids – the only water conducting cells in most woody, non flowering plants. – vessel elements – occur in several groups of plants, including angiosperm. - both are elongated, dead at maturity, lignified secondary cell walls. Tracheids Vessel elements
  23. 23. PhIoemPhIoem - Greek word phloios meaning, “bark” - transports dissolved organic / food materials from the Ieaves to the different parts of the plant - glucose in phloem moves in aII directionsTypes1. Primary phloem – differentiate from procambium and extends throughout the primary body of the plant.2. Secondary phloem – differentiates from the vascular cambium and constitute the inner layer of the bark.
  24. 24. PhIoemSieve tube elements  main conducting ceIIs of phloem  elongated and non-nucleated  uniformly thin walled with the end walls perforated to from the sieve plate.  Sieve tube element are attached end to end to form the sieve tube.
  25. 25. PhIoem
  26. 26. Call us for more information: Visit1-855-694-8886 www.iTutor.com

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