Plant Tissues

• What is a tissue?

  A group of more or less similarly diffrenated calls which performa common funcion
• What are the types of Plant tissues

  • Meristematic tissue
  • Permanent tissue
• Meristematic tissue


  Actively dividing tissue in which new cells are formed by mitosis. The cells are not yet differentiated to perform specific functions
• Differentiation


  The process during which cells or tissues undergo a change in size, shape and structure in order to perform specific functions
• Apical meristem


  Groups of cells that are found within roots and stems and are responsible for growth in length
• What are the characteristics of Apical meristem

  • Cell walls are thin
  • Vacuoles are absent
  • Cells are relatively small
  • Cells are cube-shaped
• Function of Lateral meristem

  Responsible for the increase in thickness or girth of the plant
• Permanent tissueproperties


  • Cell nuclei are large and functional
  • There are no intercellular spaces
  • Cells are highly specialised and perform specific functions
• Plant tissues

  • Epidermis
  • Parenchyma
  • Vascular tissue (xylem and phloem) -Sclerenchyma -Collenchyma
• Plant tissues


  • Dermal tissue
  • Vascular tissue
  • Ground tissue
• Dermal tissuefunction


  • Covers the plant body
  • Includes guard cells, other trichomes
• Vascular tissuefunction


  • Transports materials in the plant
  • Includes xylem and phloem
• Ground tissuefunction


  • Performs a variety of functions
  • Makes up the bulk of the plant
• Simple tissues


  Composed of one cell type
• Complex tissues


  Composed of multiple cell types
• Is a Vascular tissuea complex or simple tissue

  A complex tissue
• Woody plants have a vascular cambium that allows secondary growth and a periderm (bark) is formed
• Parenchyma


  • The most common type of plant tissue
  • Thin-walled cells with varied functions
• Collenchyma


  • Irregularly thickened cell walls, especially at the corners
• Sclerenchyma


  • Hard and thick cell walls
  • Cells are dead at maturity
• Sclerenchyma cells provide structural support and protection
• Plant tissues


  • Simple tissues
  • Compound tissues
• Simple tissues


  • Ground tissues
  • Dermal tissue
  • Vascular tissues
• Ground tissues

  Perform a variety of functions and make up the bulk of the plant body
• Dermal tissues


  Cover and protect the plant organs
• Vascular tissues


  Responsible for transport in the plant
• Tissues consisting of one cell type only are simple tissues, while those consisting of more than one cell type are compound tissues
• Vascular tissue is a compound tissue
• Epidermis


  Covers herbaceous plants, tears and dries out in woody plants and is replaced by periderm (bark)
• Tissue systems in plants

  • Dermal tissue system
  • Vascular tissue system
  • Ground tissue system
• Parenchyma


  • Thin-walled cells with large vacuoles
  • Rounded to elongated
  • Can contain chloroplasts
  • Intercellular spaces occur
• Collenchyma


  • Irregularly thickened walls, especially in the corners
  • Cells remain alive when mature
  • Found as strands in herbaceous plants
• Sclerenchyma


  • Hard and thickened walls
  • Mature forms have dead cells
• Types of sclerenchyma


  • Sclereids
  • Fibres
• Sclereids


  Have different shapes and are only found in the shells of nuts and the stones of fruit
• Fibres


  Elongated cells with pointed ends, occur in groups in wood, the inner part of bark and as part of vascular tissue
• Functions of parenchyma


  • Photosynthesis
  • Storage
  • Secretion
  • Meristematic function
  • Filling tissue
  • Aerenchyma
• Functions of collenchyma


  • Provides support
  • Strengthening in plant structure
  • Can photosynthesize when the cells contain chloroplasts
• Sclerenchyma


  A tissue that is well-suited for strengthening and support
• Herbaceous plants are covered with epidermis. In woody plants the epidermis tears and dries out eventually and a periderm (bark) is formed