Upload
jasper-obico
View
944
Download
8
Embed Size (px)
DESCRIPTION
Citation preview
2/17/2010
1
Post lab discussion
http://www.botany.hawaii.edu/faculty/Webb/BOT201/BOT201/201‐98Theme.htm#Plantae:%20Pterophyta
Vascular plants that do not produce seedsSpores onlyVascular tissues: tracheids and sieve cells
Description of Vascular Tissues which develop from Procambium
hi i id h d d iEverything inside the Endodermis
Proto means first.
2/17/2010
2
has a pith in the centerdivided Amphiphloic SiphonosteleConcentric vascular bundles with an Endodermis surrounding the bundle
Leaf gap
similar to the dictyostele but the bundles lack an endodermis and are collateral or bicollateral (open type)
perforations
collateral bundles (closed type) distributed in more that one ring within the Stem
no Endodermis
Division Psilotophyta
Division Lycophyta – Selaginella and dLycopodium
Division Pterophyta– ferns
Division Sphenophyta– horsetails or Equisetum
erect stems as well as Stolons and Rhizomes
can be epiphyticp p y
have Microphylls (leaves) and Roots
Branching is Dichotomous for both organs
2/17/2010
3
2/17/2010
4
Trabeculae‐ cells of the endodermis‐ highly elongated and span an air space
Rhizomatous, stolonRoots are dadventitious
Megaphyllpredominate organizational pattern for fern leaves is Pinnate.
produced complex stelar organization in some ferns
f h di d l hilLeafy stems have dissected steles while Rhizomes (produce few or no leaves) have relatively undissected steles.
No leaf gap with leaf gap startingto form
2/17/2010
5
cortex
endodermisxylemphloem
Aerial Stems & Rhizomes
Grooved JointedGrooved, Jointed
Microphyll, Whorled Arrangement
Leaves are fused and form a sheath around the stem at each node.
The number of tips signifies the number of leaves.
Hollow canals‐Cells Destroyed by Elongation
Central canal
2/17/2010
6
•Thick Walls
•Cutenized
•Rough Surface = Silicon
•(Nick name = Scouring Rush)
Sclerenchyma(Ridges)
Cortical (Vallecular) Canals
CollenchymaChlorenchyma
Opposite the ridges
S l lStele: eustele
caused by the destruction of Protoxylem during lElongation
May serve for conduction but not efficient
EndarchTracheids, in some vessels
lSieve elements metaxylem
protoxylem