dermal, vascular, and ground which are continuous throughout the plant.
the dermal tissue protects against pathogens, herbivores, and drought and aids in absorption of water, minerals, and carbon dioxide.
vascular tissues (xylem and phloem) facilitate the long distance transport of substances.
ground tissues function in storage, metabolism, and regeneration.
parenchyma cells are relatively unspecialized and thin walled cells that retain the ability to divide; they perform most of the metabolic functions of synthesis and storage. collenchyma cells have unevenly thickened walls; they support young, growing parts of the plant. sclerenchyma cells sclereids and fibers have thick, lignified walls that help support mature, nongrowing parts of the plant.
tracheids and vessel elements, the water conducting cells of xylem, have thick walls and are dead at functional maturity.
sieve tube elements are living but highly modified cells that are largely devoid of internal organells; they function in the transport of sugars through the phloem of angiosperms.