labeo rohita fingerlings were reared in freshwater and exposed to different concentrations of lead nitrate. after the exposure, one fish was sacrificed from each dose and the gill arches were removed. the ultrastructural changes on the gills of this cyprinid fish were investigated through scanning electron microscope (sem). lead treated gill tissues showed certain marked changes such as uplifti...

BACKGROUND Human settlements are of increasing interest to ecologists, a fact demonstrated by the recent cluster of book-length treatments of the topic (Forman 2008, McDonnell et al. 2009, Gaston 2010, Niemelä et al. 2011, Wilson 2011, Forman 2014). The natural world as a fascinating feature of towns and cities has a much longer history (e.g. Fitter 1945), and has also played a strong part in l...

The regulation of Rho of plants (ROP) in morphogenesis of leaf epidermal cells has been well studied, but the roles concerning regulators of ROPs such as RhoGDIs are poorly understood. This study reports that AtRhoGDI1 (GDI1) acts as a versatile regulator to modulate development of seedlings and leaf pavement cells. In mutant gdi1, leaf pavement cells showed shorter lobes in comparison with tho...

To investigate the involvement of the yolk-sac membrane in ion absorption, developmental changes in whole-body cation contents, cellular localization of vacuolar-type H(+)-ATPase (V-ATPase), and size and density of pavement and chloride cells in the yolk-sac membrane were examined in tilapia (Oreochromis mossambicus) larvae in fresh water (FW) and those transferred to seawater (SW) at 2 days be...

The Minnesota Department of Transportation (Mn/DOT) Office of Materials and Road Research advances the state of the practice of pavement design, construction, and maintenance by conducting and participating in pavement and materials research projects, implementation of research results, and supporting practitioners. One of the many research strategies is the study of tire-pavement noise using M...

Plastids are multifunctional, pleomorphic organelles of purported endosymbiotic origin that in plants and green algae display a characteristic double membrane envelope (Wise, 2007). All plastids originate fromcolorless proplastids, and a simple pigmentation-based classification distinguishes chloroplasts from other plastids by the presence of chlorophyll, chromoplasts by the predominance of oth...

Hagfish (Eptatretus burgeri) are agnathous and are the earliest vertebrates still in existence. Pavement cells adjacent to the mitochondria-rich cells show orthogonal arrays of particles (OAPs) in the gill of hagfish, a known ultrastructural morphology of aquaporin (AQP) in mammalian freeze-replica studies, suggesting that an AQP homolog exists in pavement cells. We therefore cloned water chann...

Plastids are multifunctional, pleomorphic organelles of purported endosymbiotic origin that in plants and green algae display a characteristic double membrane envelope (Wise, 2007). All plastids originate fromcolorless proplastids, and a simple pigmentation-based classification distinguishes chloroplasts from other plastids by the presence of chlorophyll, chromoplasts by the predominance of oth...

Dicot leaves are composed of a heterogeneous mosaic of jigsaw puzzle piece-shaped pavement cells that vary greatly in size and the complexity of their shape. Given the importance of the epidermis and this particular cell type for leaf expansion, there is a strong need to understand how pavement cells morph from a simple polyhedral shape into highly lobed and interdigitated cells. At present, it...

Cells dissociated from normal prelactating mouse mammary glands or from spontaneous mammary adenocarcinomas, when grown at high density on an impermeable substrate, form nonproliferating, confluent, epithelial pavements in which turgid, blister-like domes appear as a result of fluid accumulation beneath the cell layer. To compare the structure of the fluid-segregating cell associations in norma...