IT’S A IT’S A GREEN GREEN WORLDWORLD

Transport in Transport in plantsplants

Transpiration - recapTranspiration - recap

Private life of plants - xylem, phloem Private life of plants - xylem, phloem animationanimation

StarterStarterHow can you tell the age of a tree How can you tell the age of a tree

stump?stump?

Tree rings showing variation in growth from year-to-year, a function of changes in climate

Count the growth rings

Transport in plantsTransport in plants

Learning objectivesLearning objectives Relate plant structure Relate plant structure

to functionto function

Describe the Describe the arrangement of xylem arrangement of xylem and phloem in plantsand phloem in plants

Describe the structure Describe the structure of xylem and phloem of xylem and phloem and relate it to functionand relate it to function

Success criteriaSuccess criteria

Students should be able Students should be able to:to:

Identify the xylem in Identify the xylem in plant stemsplant stems

Draw a diagram Draw a diagram showing the basic showing the basic structure and structure and arrangement of xylem arrangement of xylem and phloem in roots, and phloem in roots, stems and leaves.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.

Leaves are entry and exit points for the gases needed by plants.

Roots absorb water and minerals from the soil.

Stems connect the roots to the leaves, flowers and fruits. They contain cells specially adapted for transportation of water, minerals and sugars.

Flowers allow the plant to reproduce

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Which cells transport nutrients?

The cells are arranged in plants as vascular bundles.

Plants contain two types of cell adapted for transportation.

Phloem cells transport sugars produced in the leaves up and down the stem to growing and storage tissues.

Xylem cells transport water and minerals up the stem from the roots to the shoots and leaves. This transport occurs in one direction only.

Both phloem and xylem form continuous systems connecting roots, stems and leaves.

Inside a plant stem

Transport in plantsTransport in plants

Examine the plants that have been Examine the plants that have been standing in dye for 2 days.standing in dye for 2 days.

Can you identify the xylem?Can you identify the xylem?

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What are vascular bundles?

Transport in plantsTransport in plants

Using the textbook draw the Using the textbook draw the arrangement of the vascular arrangement of the vascular bundles (xylem and phloem) in:bundles (xylem and phloem) in:

A rootA root

A stem A stem

A leafA leaf

How is xylem adapted for transportation?

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.

Remember that water and minerals travel in xylem vessels.

The sugars are carried to growing parts and storage parts such as fruit.

How is phloem adapted to transportation?

Phloem cells are living and carry sugars.

The cells are sometimes called sieve tubes and are separated by structures with holes called sieve plates.

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Cells in the vascular bundles

Transport in plantsTransport in plants

Learning objectivesLearning objectives Relate plant structure Relate plant structure

to functionto function

Describe the Describe the arrangement of xylem arrangement of xylem and phloem in plantsand phloem in plants

Describe the structure Describe the structure of xylem and phloem of xylem and phloem and relate it to functionand relate it to function

Success criteriaSuccess criteria

Students should be able Students should be able to:to:

Identify the xylem in Identify the xylem in plant stemsplant stems

Draw a diagram Draw a diagram showing the basic showing the basic structure and structure and arrangement of xylem arrangement of xylem and phloem in roots, and phloem in roots, stems and leaves.stems and leaves.