Hawaiian
Ethnobotany-Anatomy-13 
Hawaiian
Ethnobotany-Anatomy-13 
Ground Tissue-3
Sclerenchyma is the principal Support Tissue in Plants.
Its cells have
extremely Thick & highly Organized
Walls.
The Walls are often impregnated with Lignin. This gives
them the strength of Steel.
The cells are often elongated & have overlapping end walls which adds strength. These cells
are called Fibers.
Fibers occur in cylindrical bundles which resemble the
steel rods in reinforced concrete.
Fiber Bundles are often associated
with Vascular Tissue.
They may also surround Vascular Bundles like a sheath. The term
Fibrovascular Bundle is used for the
latter.
 Stem of the Wax Plant (Hoya): The Parenchyma cells have pink walls. There is a band of Sclerenchyma cells which have stained Blue. |
  Sclerenchyma cell from Hoya |
 Cross-section of Asparagus Stem: A continuous band of Sclerenchyma can be seen. |
 |
 Podocarpus Leaf Section with prominent Sclerenchyma |
 Sclerenchyma Cell from Podocarpus Leaf: Note the extremely thick Cell Wall! |
 Section through a Fiber Bundle: The red stain indicates the presence of Lignin. |
 The cell walls of these Fibers occupy most of the cell volume. These are also Lignified. |
 Fibers isolated from Oak: These do not look strong but when many occur together they are strong enough to support trees that are several hundred feet high. Note the overlapping end walls on the Fibers to the right ..........  |
 |
 Large Fibrovascular Bundle from makaloa: Note the Fibers which surround the Vascular Tissues (Phloem & Xylem) |
 Some Sclerenchyma cells can have elaborate shapes. This is an Astrosclereid from Water-lily. These may deter herbivory. |
