- Describe the shape of the guard cells and normal epidermal cells.
- Which epidermal cells have chloroplasts?
- Describe the wall thickness around the guard cells and account for any visible differ-
ences.
We will now look at parenchyma, collenchyma and sclerenchyma cells. Together these
tissue types are referred to asground tissues. Ground tissues are located in the region
between epidermal and vascular tissue.
Parenchyma tissue DUMMY
Parenchyma tissue forms the majority of stems and roots as well as soft fruit like tomatoes
and grapes. It is the most common type of ground tissue.
Figure 5.9: Parenchyma tissue found in cells responsible for storage.
Parenchyma
Structure Function
Thin-walled cells. Thin walls allow for close packing and
rapid diffusion between cells.
Intercellular spaces are present between
cells.
Intercellular spaces allow diffusion of
gases to occur.
Parenchyma cells have large central
vacuoles.
This allows the cells to store and regulate
ions, waste products and water. Also
function in providing support.
Specialised parenchyma cells known as
chlorenchymafound in plant leaves
contain chloroplasts.
This allows them to perform a
photosynthetic function and responsible
for storage of starch.
Some parenchyma cells retain the ability
to divide.
Allows replacement of damaged cells.
122 5.3. Plant tissues