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Unformatted text preview: all starting with the letter “P”. Characteristics of cork • Several layers of thin walled and flattened cells that die at maturity • Walls have suberin (waxy fat impermeable to water; the same chemical found in the casparian strips of the root endodermis layer, and in the abscission zone in leaves. Walls may also contain lignin.) • Provides mechanical protection to stem • There may be a region of parenchyma cells produced interior to the cork cambium, too. The cork parenchyma cells can be called phelloderm (another term that can be ignored). Early cork Lenticels Lenticels in Bark Cork is generally impervious to fluids and gases so that special structures for gas exchange are required to provide oxygen to the living cells of the secondary growth region. Lenticels are weak "eruptions" of parenchyma cells through which gases can diffuse. Lenticels also contribute to the appearance of bark...
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This note was uploaded on 01/08/2012 for the course BIO 213 taught by Professor Makina during the Fall '09 term at SUNY Stony Brook.
- Fall '09