Leaves
 When
the leaf blade is in one piece, it is
called simple.
 Examples
of plants with this type of leaf are
corn, oak, and fig.
 When
the leaf is made up of two or more
leaflets, it is called compound.
 These
leaves may be pinnately compound or
palmately compound.
 Pinnately
compound leaves have a single
stalk with many leaflets.
 Examples
of this kind of leaf are mesquite,
rose, and pea.
 Palmately
compound leaves are made up of
many leaflets, but all are attached to the
stalk at one point.
 Examples
of this kind of leaf are the Virginia
creeper, poison ivy
 What
is venation?
 The arrangement of veins in the leaves is called
venation. The two types are parallel and netted.
 Parallel venation- veins run in the same direction.
Example: most grasses.
 Netted venation- veins that form a net. Examples:
flowers, mulberry, cottonwood.
 The two types of netted venation are pinnately and
palmately
Netted
Parallel
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Epidermal Cells- protects underlying cells from damage.
Cutin/ Cuticle- layer of wax, keeps plants from drying out.
Guard Cells- regulate the release of water and gasses.
Stomata- opening in the leaf that allow gas exchange and
water movement.
Palisade layer- rich in chlorophyll
Spongy layer- cells that exchange gasses, border the
intercellular chamber.
Vascular Bundle- vein system consisting of phloem and
xylem tissues. Phloem transports food from the leaf to
other part of the plant, while the xylem transports water
and dissolved minerals to the leaves.
Intercellular Chamber- allows for the free movement of
water from cell to cell
 “Why

do plants have leaves?”
Answer: leaves are the main source of energy for
plants