Pavement cells

Gillmor et al. 2002). The embryos of nonconditional AtCESAl mutants are radially swollen in appearance, indicating decreased elongation even at early stages. Although the pattern of cell division appears relatively normal, incompletely formed cell walls are observed frequently (Beeckman et al. 2002). The epidermis of the mutants is markedly affected with an apparent complete loss of guard cells and pavement cell crenulation (Beeckman et al. 2002). 

Wendelaar Bonga, S.E., and J.C.A. Van der Meij (1989). Degeneration and death, by apoptosis and necrosis, of the pavement and chloride cells in the gills of the teleost Oreochromis mossambi-cus. Cell Tissue Res. 255 235-243. 

Figure 4.13. Illustration of the MCPA. The lattice is uncoupled into cells (here of four sites) forming a pavement. The real configuration around a single cell is replaced by a lattice of effective (identical) cells, determined by the vanishing of the mean scattering on the central cell.

The epithelial cells are closely packed together like a pavement, forming not only an effective barrier to most micro-organisms, but also for active substance absorptirMi. The low permeability of the cornea is due to the presence of tight junctions between the epithelial cells. The superficial corneal epithelial cells are exfoliated from the ocular surface, their average life is 4—8 days. 

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