PLANT TISSUES

• Tissue


  A group of cells that perform a common function and have a common origin that has been modified to perform that particular cell function
• Types of tissues


  • Meristematic
  • Permanent
• Meristematic tissues


  • Small sized living cells, No intercellular space, Distinct cell nucleus, Small central vacuoles, No chloroplast, Large number of mitochondria
• Types of meristematic tissues

  • Apical meristems (shoot/root apex, axillary bud)
  • Intercalary meristems (nodes)
  • Lateral meristems (lateral stems, roots)
• Permanent tissues


  Tissues that lose the ability to divide and become specialised to perform a known function
• Types of permanent tissues

  • Simple permanent
  • Complex permanent
• Parenchyma


  • Living cells, Isolated with a large central vacuole, Nucleus present peripherally in cytoplasm, Cell wall is thin and made up of cellulose, Intercellular spaces
• Collenchyma


  • Living cells, Thickened corners of the cell wall, May or may not have intercellular spaces, Elongated cells with polygonal cross section
• Sclerenchyma


  • All cells are dead, Lignin is deposited on cellulose cell wall, No intercellular space, Forms central lumen
• Phloem


  • Sieve tube elements, Companion cells, Phloem parenchyma, Phloem fibers
• What's a tissue? 


  Group of cells with a common origin that's modified to perform a particular function
• What's meristematic? 


  Divide by meiosis to produce new daughter cells