Download VASCULAR PLANTS

VASCULAR PLANTS
CELLSTISSUESORGANSORGANS
FORM AND FUNCTION
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Everything about a vascular plant is geared
towards one process…
 PHOTOSYNTHESIS
 CO2 + H2O C6H12O6 + O2
PLANT CELLS
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Recall: plant cells have cell walls,
chloroplasts and large central water vacuole.
OVERVIEW – ROOT AND SHOOT
SYSTEM
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Root system is below
the ground
Shoot system is above
the ground and can
include stems, leaves
and sometimes flowers.
ORGANS
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Leaf: primary site of photosynthesis
Stem: conduction of water and dissolved
minerals and sugars and structure and
support
Root: anchorage; absorption of water and
dissolved minerals
Flower: seed production
TISSUES
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Each type of tissue is continuous throughout
the plant structure
Each tissue contains cells that are adapted to
perform a specific function
GROUND

Has multiple functions and makes up most of
the inside of a plant
–
–
–
Parenchyma: storage, photosynthesis, gas
exchange, protection, tissue repair and
replacement.
Collenchyma: support surrounding tissues,
provided flexibility for plant, tissue repair and
replacement
Schlerenchyma: support of the mature plant
DERMAL

the outer layers of cells that
form a protective covering
for the plant
– Includes the epidermis
and the periderm
 Guard cells are cells
found in the upper
and lower epidermis
of leaves and
perform gas
exchange through
the stoma (hole)

Trichomes – tiny
growths on the
leaves and stems of
some plants that can
make the plant
appear fuzzy or
wooly. Help keep
leaf surfaces cool
and some secrete
toxic substances that
repel herbivores.
 Root
Hairs: fine hair like structures that cover
the surface of the root of a plant. They
increase the surface area available for gas
exchange and absorption of water by the roots.
VASCULAR
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System of tubes that run lengthwise
throughout the stem of a plant and connect
the roots to the leaves
What system in animals does this remind you
of?
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XYLEM: transports water
and dissolved minerals from
roots to leaves (ONE WAY!!)
Consists of tracheids and
vessel elements. Vessel
elements are long
continuous tubes formed
from dead, hollow,
cylindrical cells arranged
end to end. Tracheids are
dead cells that taper at the
ends and overlap one
another
XYLEM IS DEAD!!

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Pholem transports organic nutrients (sugars)
often from the leaves (source) to wherever
the sugars are needed (sink). The roots can
store excess sugar, but actively growing
regions may need the sugar. It just depends.
This process is known as TRANSLOCATION
How does phloem work?
MERISTEMATIC TISSUE
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Its kind of like the stem cells for plants
Undifferentiated embryonic plant tissue from
which all other plant tissues develop
These tissues contain cells which are
undergoing rapid division
–
–
Apical or intercalary meristems – found along
stems or at the base of leaf blades
Lateral meristems – increases circumference or
girth of stems