Xylem and phloem lesson 2
-
Upload
tre-briercliffe -
Category
Education
-
view
3.873 -
download
0
description
Transcript of 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