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Vascular Systems in plants – an introduction to plant anatomy. Cells & Tissues. Organization into structural entities. Endodermis. Pericycle. primitive vascular plants. Lycopodium gnidiodes. primitive vascular plants. Lycopodium claviatum. PROTOXYLEM. PROTOXYLEM PHLOEM.
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Vascular Systems in plants – an introduction to plant anatomy Cells & Tissues. Organization into structural entities.
Endodermis Pericycle primitive vascular plants Lycopodium gnidiodes
primitive vascular plants Lycopodium claviatum
PROTOXYLEM PROTOXYLEM PHLOEM Detail of a cross section of the stem of Psilotum primitive vascular plants Psilotum has no leaves or roots!
XYLEM PHLOEM TRABECULA primitive vascular plants Trabeculae are modified endodermal cells – pericycle surround vascular bundle.
PERICYCLE PHLOEM ENDODERMIS primitive vascular plants Rumohra
PHLOEM FIBERS FIBERS PROTOPHLOEM Encephalartos. Gymnosperm
PHLOEM RAY TRACHEIDS CAMBIUM PHLOEM Araucaria (Gymnosperm)
EXTERNAL PHLOEM INTERNAL PHLOEM Cucurbita
Zea maysMonocotyledon. (Atactostele) highly advanced
Nymphoides stem Hydrophytes have a reduced xylem component in the vascular system. Here, only a few XYLEM VESSELS are visible. The phloem on the other hand appears to be well-developed, and consists of sieve tubescompanion cells and phloem parenchyma. 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
cambium The pine leaf sunken stomate In Gymnosperm leaves such as the pine leaf, the vascular system is reduced to the central region. You should be able to see two vascular bundles in this example. The xylem is composed of TRACHEIDS and the phloem of SIEVE CELLS and ALBUMINOUS CELLS. endodermis vascular bundle endodermis