28378B

28378B
Caption: Stem surface of a prickly pear cactus (Opuntia spp.) showing sunken stomata. Cacti typically have sunken stomata, which are an adaptation to drought conditions. An additional adaptation to a harsh environment is the fine covering of wax across the leaf or stem surface. Stomata (plural of stoma) are tiny openings in the epidermis of a plant that are surrounded by pairs of crescent-shaped cells, called guard cells (specialized parenchyma cells), that facilitate gas exchange. Stomata are present in the sporophyte generation of all land plant groups except liverworts. Prickly pear cacti typically grow with flat, rounded platyclades that are armed with two kinds of spines; large, smooth, fixed spines and small, hair like spines called glochids that easily penetrate skin and detach from the plant.
Magnification*: x34
Type: SEM
Copyright 2008 Dennis Kunkel Microscopy, Inc.
Keywords: 07.01.08,28378B,leaf,leaf stoma,leaf stomata,leaf stomate,leaf stomates,plant,plants,stoma,stomata,stomate,stomates,guard cell,guard cells,leaf epidermis,leaf surface,gas exchange,plant cell,plant cells,desert plant,desert plants,succlent plants,Cactaceae,Opuntia,prickly pear,prickly pear cactus,prickly pear cacti,cacti,cactus,stem stoma,stem stomata,stem stomate,stem stomates,platyclade,platyclades,glochids,parenchyma cell,parenchyma,parenchyma cells,plant cuticle,wax cuticle,plant epidermis,drought,drought plant,drought plants,stem surface,succulent plant