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IT’S A
GREEN WORLD
Transport in plants
Transpiration - recap
 Private life of plants - xylem, phloem
animation
Starter
How can you tell the age of a tree stump?
Count the growth rings
Tree rings showing variation in
growth from year-to-year, a
function of changes in climate
Transport in plants
Learning objectives
 Relate plant structure
to function
 Describe the
arrangement of xylem
and phloem in plants
 Describe the structure
of xylem and phloem and
relate it to function
Success criteria
Students should be able
to:
 Identify the xylem in
plant stems
 Draw a diagram showing
the basic structure and
arrangement of xylem
and phloem in roots,
stems and leaves.
How are plants adapted for transport?
The structures of cells and tissue in different parts of the
plant are adapted to allow transportation of essential
materials.
Flowers allow the plant to reproduce
Leaves are entry and exit
points for the gases
needed by plants.
Stems connect the roots to
the leaves, flowers and fruits.
They contain cells specially
adapted for transportation of
water, minerals and sugars.
Roots absorb water and
minerals from the soil.
Which cells transport nutrients?
Plants contain two types of cell adapted for transportation.
Xylem cells transport water and minerals
up the stem from the roots to the shoots
and leaves. This transport occurs in one
direction only.
Phloem cells transport sugars produced
in the leaves up
and down the stem to growing and
storage tissues.
The cells are arranged in plants as vascular bundles.
Both phloem and xylem form continuous systems connecting roots,
stems and leaves.
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© Boardworks Ltd 2007
Inside a plant stem
Transport in plants
 Examine the plants that have been
standing in dye for 2 days.
 Can you identify the xylem?
What are vascular bundles?
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© Boardworks Ltd 2007
Transport in plants
Using the textbook draw the
arrangement of the vascular bundles
(xylem and phloem) in:
 A root
 A stem
 A leaf
How is xylem adapted for transportation?
Remember that water and
minerals travel in xylem
vessels.
Xylem vessels are strengthened
by a substance called lignin.
Lignin is produced in dead cells.
The thick walls of xylem cells also
help support plants.
How is phloem adapted to transportation?
Phloem cells are living and carry
sugars.
The sugars are carried to
growing parts and storage
parts such as fruit.
The cells are sometimes called
sieve tubes and are separated
by structures with holes called
sieve plates.
Cells in the vascular bundles
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© Boardworks Ltd 2007
Transport in plants
Learning objectives
 Relate plant structure
to function
 Describe the
arrangement of xylem
and phloem in plants
 Describe the structure
of xylem and phloem and
relate it to function
Success criteria
Students should be able
to:
 Identify the xylem in
plant stems
 Draw a diagram showing
the basic structure and
arrangement of xylem
and phloem in roots,
stems and leaves.