vascular systems in plants – an introduction to plant anatomy cells & tissues. organization...
TRANSCRIPT
Vascular Systems in plants – an introduction to plant anatomy
Cells & Tissues. Organization intostructural entities.
Lycopodium
gnidiodes
PericycleEndodermis
primitive vascular plants
Lycopodium claviatum
primitive vascular plants
PROTOXYLEM
Psilotum has no leaves or roots!
PROTOXYLEM
PHLOEM
Detail of a cross section of the stem of Psilotum
primitive vascular plants
TRABECULA
XYLEMPHLOEM
Trabeculae are modified endodermal cells – pericycle surround vascular bundle.
primitive vascular plants
Rumohra
ENDODERMIS
PERICYCLE
PHLOEM
primitive vascular plants
FIBERS
PROTOPHLOEM
PHLOEM FIBERS
Encephalartos.Gymnosperm
PHLOEM
TRACHEIDS
RAY
CAMBIUM
PHLOEM
Araucaria (Gymnosperm)
INTERNAL PHLOEM
EXTERNAL PHLOEM
Cucurbita
Zea mays Monocotyledon.
(Atactostele) highly advanced
Nymphoides stem
Hydrophytes have a reduced Hydrophytes have a reduced xylem component in the xylem component in the vascular system. Here, only a vascular system. Here, only a few XYLEM VESSELS are few XYLEM VESSELS are visible. The phloem on the visible. The phloem on the other hand appears to be well-other hand appears to be well-developed, and consists of developed, and consists of sieve tubessieve tubes companion companion cellscells and and phloem phloem parenchymaparenchyma. I. I
Several ASTROSCLERIEDS can be seen interspersed with the ground parenchyma
Ligustrum (Privet) Leaf
Advanced foliage leaf, dicotyledon.Note mesophyll divided into upper palisade and lower spongy layer.Smaller veins (like these) are embedded within the mesophyll, between palisade and spongy layers.
These are MINOR veins
Zea mays leaf
The pine leaf
In Gymnosperm leaves such as the In Gymnosperm leaves such as the pine leaf, the vascular system is pine leaf, the vascular system is reduced to the central region. You reduced to the central region. You should be able to see two vascular should be able to see two vascular bundles in this example.bundles in this example.The xylem is composed of The xylem is composed of TRACHEIDSTRACHEIDS and the phloem of and the phloem of SIEVE CELLSSIEVE CELLS and and ALBUMINOUS ALBUMINOUS CELLS.CELLS.
vascular bundlecambium
endodermis
endodermis
sunken stomate