xylem and phloem lesson 2

Label and annotate the phloem, xylem and meristem on the laminates

2. Flowering plants have two tissues to transport materials, xylem and phloem. The diagram below shows the outline of a transverse section of the root of a dicotyledonous flowering plant.Sketch in and label the areas occupied by the xylem and phloem.

[Total 2 marks]Booklet Page 6

Memorise this….

Recreate!

Xylem

XylemHollow Dead cells end to endContinuous Tubes (Narrow)Strengthened with Lignin

Pits in wallAllow movement across

No cell contents, no nucleus or cytoplasm, no end walls

Structure/Feature How adaptation worksDead cells aligned end to end in a continuous columnNarrow tubesLignin deposited in the wallsPits in the lignified wallsNo end walls or cell content

How Xylem is Adapted for its role:

Page 7

Memorise this….

Recreate!

Phloem

Two types of cell: Sieve Tube elements and Companion Cells

Sieve Tube elements:

Little cytoplasm and no nucleusEnd to end to make a tube

Cross walls perforated by pores – Sieve plates

Phloem

Companion Cells

Large nucleus and dense cytoplasm

Lots of mitochondria – ATP for active processes

Linked by plasmodesmata

Structure/Feature How adaptation worksSieve tube element

Mitochondria in companion cellLittle cytoplasm

plasmodesmata

How Phloem is Adapted for its role:

Label diagrams in booklet and make sure key words defined

On mini wb:1.Describe the structure of a xylem vessel2.Why do xylem vessels have pits3.Explain why sieve tube elements are not true cells

Xylem Phloem

Both Xylem and Phloem