Why do all plants need a transport system?
All living things take substances from environment and return wastes. Every cell of a plant needs a regular supply of water and nutrients. Many cells inside the plant are far away from the supply, they wouldnt not receive enough nutrients without a transport system.
Xylem and phloem in the young root..
Vascular bundles are found in the centre of a young root. There is a central core of Xylem, usually the shape on an 'X'. Phloem is found in between the arms of the X-shaped Xylem. This arrangement provides strength to withstand the pulling forces to which roots are exposed. Around Vascular bundle is a sheath of cells called the endodermis, which gets water into the xylem vessels. Inside the endodermis is meristem cells.
Xylem and Phloem in stem ..
Vascular bundles found at outer edge of the stem. Ring like arrangement provides strength and flexibility to withstand the bending forces to which stems and branches are exposed. Xylem is found towards inside of each vascular bundle. Phloem is found towards outside of vascular bundle. In between these two is the cambium, which is a layer of meristem cells that divide to produce either new xylem or phloem.
Xylem and Phloem in the leaf..
Vascular bundles form the midrib and veins of a leaf. A dicotyledon leaf has a branching network of veins that get smaller as they spread away from the midrib. Within each vein, xylem can be seen on top of the phloem.
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