Leaf Anatomy
Close-up of leaf, showing conceptacles.
Conceptacle x.s., showing sterile "hairs", 25x.
Nonreproductive
conceptacles are visible on the leaf surface as dark spots. A cross-section
through one shows its structure. In a fertile conceptacle, the sterile
hairs would be accompanied by antheridia or oogonia.
Leaf x.s., 25x.
A
cross-section through the entire leaf shows differentiation into epidermis,
cortex, and medulla. The epidermis may be differentiated into a meristoderm
and cuticle.
(above) Leaf epidermis and outer cortex, 25x. Polarized.
(below) Leaf epidermis and outer cortex, 25x. Non-polarized.
Leaf surface, 63x. Partly polarized.
A
cross-section through the leaf surface shows both a pigmented epidermal
layer and an unpigmented inner cortical layer. Note the large size of the
cortical cells as compared to the epidermal cells. A partly polarized view
of the surface of the leaf also shows the pigmented epidermal cells.
(above) Leaf cortex, 160 x, unpolarized.
(below) Leaf cortex, 160x, polarized.
Leaf cortex and epidermis, stained with aniline blue. 100x.
(above)Medulla and cortex, stained with aniline blue, polarized. 100x.
(below) Medullary cells, 160x.
A
stained cross-section through the cortex shows the thick cell walls more
clearly. Note the absence of staining within the cells. A medullary cross-section
shows what may be the uptake of stain by the conductive cells (this image
is polarized, so the cell walls are birefringent). Non-stained images of
the medulla show the more densely pigmented and smaller cells, with thicker
cell walls as compared to the epidermis. Because of this pigmentation,
it is difficult to tell whether there is a great deal of stain uptake in
these cells.
(above) Transverse section through leaf, polarized and stained with aniline blue. Long axis is oriented vertically. 25x.
(below) Transverse section through medulla, axis oriented horizontally. 100x.
A
transverse section through the leaf shows the elongated medullary cells.
A closer view shows the presence of what look like sieve plates between
adjoining cells.
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