Leaf Anatomy
Cross Section of a Leaf
Leaf Tissues
A leaf is considered a plant organ and typically consists of the
following tissues:



An epidermis that covers the upper and lower surfaces
An interior parenchyma called the mesophyll
An arrangement of veins (the vascular tissue).
Epidermis
The epidermis is the outer one- or multi-layered group of cells
covering the leaf.
The epidermis has several functions:
- protection against water loss (a vaxy cuticle)
- regulation of gas and water vapor exchange (stomata)
- secretion of metabolic compounds
- absorption of water (in some species) .
A multi-layered epidermis
Mesophyll
means "middle of the leaf", i.e. the tissues of a leaf that are
located in between the layers of epidermis and carry on
photosynthesis.
The mesophyll of the leaf consists of parenchyma tissue.
Since the mesophyll cells contain chloroplasts the tissue is
also referred to as chlorenchyma .
Chlorenchyma cell
Functions of the Mesophyll
In most dicot leaves the mesophyll is differentiated into
palisade parenchyma (A) and spongy parenchyma (B).
The palisade cells are responsible for photosynthesis because
they contain chloroplasts.
The spongy mesophyll, together with the intercellular air
spaces, allow for the interchange of gases
Vascular Tissue
Vascular tissue is a complex tissue.
 The primary components of vascular tissue
are the xylem and phloem. These two tissues transport fluid
and nutrients.
 Vascular tissue is organized into discrete strands called
vascular bundles.
Cross Section of Papyrus Leaf
e epidermis
bb bulliform cells(they cause the leaf to roll up in response
to low water availability )
skl sclerenchyma
cs vascular bundle
Clivia leaf cross section
silná kutikula, ztlustlá epidermis
The epidermis has a thick cuticle.
European Yew (Taxus baccata)
Cross Section of a Needle
X – xylem
f - phloem
skl –
sclerenchyma
e – epidermis
ku – cuticle
ka – cambium
pp – palisade
parenchyma
hp – spongy
parenchyma
Rubber fig (Ficus elastica)
Cross Section of a Leaf
pp - palisade parenchyma
e - epidermis
cs - vascular bundle
hp - spongy parenchyma
ku - cuticle
st - stoma
Resources
Internet:
http://www.ueb.cas.cz/laboratory_of_pollen_biology/pdf_subo
r/anatomie_list.pdf
http://cs.wikipedia.org/wiki/List#Anatomick.C3.A1_stavba_lis
tu
http://botany.upol.cz/atlasy/anatomie/anatomieCR28.pdf
commons.wikimedia.org
http://www.uri.edu/cels/bio/plant_anatomy/
www.sci.muni.cz/~anatomy/leaves/html/papyrus_1.htm
Thanks for your attention
Lenka Rydvalova