1 / 27

PLANT TISSUES

PLANT TISSUES. CHAPTER 7 General Botany. Tissues. - are group of ceIIs performing the same function - ceIIs that are structurally and/functionally similar Types: A. Meristematic tissues (meristems) B. Permanent tissues . A. Meristematic tissues.

steve
Download Presentation

PLANT TISSUES

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. PLANT TISSUES CHAPTER 7 General Botany

  2. Tissues - are group of ceIIs performing the same function - ceIIs that are structurally and/functionally similar Types: A. Meristematic tissues (meristems) B. Permanent tissues

  3. A. Meristematic tissues - composed of actively dividing ceIIs, responsible for the production of ceIIs. Kinds of meristems: • Apical meristems –found at the tip of stems & roots • Lateral meristems –a.k.a. cambia (singular:cambium) - 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

  4. B. Permanent tissues - tissues that attained their mature form and perform specific functions - they stop dividing Types: • Simple permanent tissues • Complex permanent tissues

  5. Simple permanent tissues -consist only of one kind of cells A. Dermal / surface tissue - external tissues - forms protective covering of the plant body a. epidermis b. periderm

  6. Epidermis - the outermost layer of the primary plant body - covers the leaves, floral parts, fruits, seeds, stems 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)

  7. Structure of epidermis

  8. Stomata -pores for gas exchange - present on one or both surfaces of Ieaves epidermaI ceIIInner waII of the guard ceII nucIeus stomataI porechIoropIast

  9. Cuticle – Iines the outer waII of the epidermal ceIIs - made up of waxy material that protects plants from desiccation

  10. trichomes – outgrowths of epidermal ceIIs -

  11. Periderm (Bark) -is the outermost layer of stems and roots of woody plants such as trees.

  12. B. Ground tissues 1. 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, fruits Functions: *basic metabolic function(respiration, photosynthesis (chIorenchyma in Leaf) & protein synthesis) *storage (potatoes, fruits, & seeds) *wound healing and regeneration

  13. chIorenchyma- a specialized parenchyma tissue found in the green parts of the shoot and performs photosynthesis.

  14. 2. CoIIenchyma -Greek word kolla which means “glue” - cells are elongated (up to 2mm long) with unevenly thickened walls ( thin on the sides but thick at the angles where 2 or more cells meet) - differentiate from parenchyma cells & are alive at maturity Functions: • Support & elasticity (stem surfaces & along leaf veins) • regeneration

  15. 3. 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 mature Types: 1. scIereids or stone cells 2. fibers

  16. fibers

  17. scIereids in pear fruit

  18. Complex Permanent Tissues Vascular 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 Ieaves • types 1. Xylem 2. phloem

  19. Xylem - GW xyIosw/c means “wood” - transports water and dissolved nutrients from the roots to aII parts of a plant. - direction of transport is upward 2 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.

  20. 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

  21. longitudinal section cross sectionPrimary xylem

  22. PhIoem - 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 directions Types 1. Primary phloem – differentiate from procambium and extends throughout the primary body of the plant. 2. Secondary phIoem – differentiates from the vascular cambium and constitute the inner layer of the bark.

  23. Sieve tube elements– main conducting ceIIs of phloem - elongated and non-nucleated - uniformly thin walled with the end walls perforated to from thesieve plate. - sieve tube element are attached end to end to form the sieve tube.

More Related