Ultrastructure of cells

Many UVB-induced physiological effects such as declining photosynthetic rates can be related not only to damaged biomolecules, but also to ultrastructural changes in organelles or membranes (Holzinger and Lutz 2006). Typical alterations include 

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Muhlethaler K 1975 The ultrastructural of cells. In Davies P (ed) Historical and current aspects of plant physiology A symposium honoring F. C. Steward. NY State Coll Agr Life Sci Cornell Univ Ithaca, 226 - 242... 

P. M. Elias, S. H. Yuspa, M. Gullino, D. L. Morgan, R. R. Bates, and M. A. Lutzner, In vitro neoplastic transformation of mouse skin cells Morphology and ultrastructure of cells and tumors, / Invest. Dermatol. 62, 569-581 (1974). 

Pickett-Heaps, J.D. (1967). The effects of colchicine on the ultrastructure of dividing plant cells, xylem wall differentiation and distribution of cytoplasmic micrombules. Dev. Biol. 15, 206-236. 

Hussey, R.S. and Mims, C.W. (1991) Ultrastructure of feeding tubes formed in giant-cells induced in plants by the root-knot nematode Meloidogyne incognita. Protoplasma 162, 99-107. 

Hussey, R.S., Mims, C.W. and Westcott, S.W.I. (1992) Ultrastructure of root cortical cells parasitized by the ring nematode Criconemella xenoplax. Protoplasma 167, 55-65. 

The site of pheromone production is varied amongst the insects just as there are variable structures in the different orders. Several reviews are available detailing the ultrastructure of these glands [9-11]. Evidence that pheromone biosynthesis occurs in these cells and tissues requires that the isolated tissue be shown to incorporate labeled precursors into pheromone components. In the more studied model insects this criteria has been met. 

Experiment 5. Observation under transmission electron microscope We compared the TEM ultrastructure of the seed coat and endosperm of control and rue-treated seeds The palisade layer of treated seed appears thicker than in the control (Figs 6A and 7A), while comparison between aleuronic cells of the control and treated cells (Figs. 6B and 7B), reveals that the cells of the control are healthy with some evident organelles such as the nucleus and the rough endoplasmic reticulum and other structures, the plastid, the plasmodesmata, conspicous constrictions, protein bodies and... 

Lesser, M.P. and J.M. Shick. 1990. Effects of visible and ultraviolet radiation on the ultrastructure of zoox-anthellae (Symbiodinium sp.) in culture and in situ. Cell Tiss. Res. 261 501-508. 

HosakaY, Taguchi K, Iwamoto T, Kuroda K, Tsuruoka H, Xu H, Hamaoka T. Ultrastructure of murine tumour cell lines defective in MHC class I expression before and after interferon-y treatment. J Electron Microsc 1998 47 495-503. 

Casern, M. L., Tran, L. P. P., and Moore, A. M. F. (2002). Ultrastructure of the major ampullate gland of the black widow spider, Latrodectus hesperus. Tissue Cell 34, 427-436. 

Paul NA, Cole L, de Nys R, Steinberg PD (2006) Ultrastructure of the gland cells of the red alga Asparagopsis armata (Bonnemaisoniaceae). J Phycol 42 637-645 Paul VJ, Cruz-Rivera E, Thacker RW (2001) Chemical mediation of macroalgal-herbivore interactions ecological and evolutionary perspectives. In McClintock JB, Baker BJ (eds) Marine chemical ecology. CRC, pp 227-265... 

Because disrupted tissue preparations were unsatisfactory, attempts were made to work either with more organized systems such as tissue slices (liver-Krebs) or to identify and isolate the intracellular organelles involved in the reactions. Cytochemical procedures were developed in the 1930s and 1940s to locate sites of reaction in situ in cells (Chapter 9). Examination of cell ultrastructure became possible when the electron microscope was introduced after 1945. Techniques for the isolation of cell organelles, notably mitochondria, were developed about this time (Chapter 9). 

Electron micrographs of cell ultrastructure become available. 

Figure 11.1 Ultrastructure of the human lung alveolar barrier. The tissue specimen is obtained via lung resection surgery. (A) Section through a septal wall of an alveolus. The wall is lined by a thin cellular layer formed by alveolar epithelial type I cells (ATI). Connective tissues (ct) separate ATI cells from the capillary endothelium (en) within which an erythrocyte (er) and granulocyte (gc) can be seen. The minimal distance between the alveolar airspace (ai) and erythrocyte is about 800-900 nm. The endothelial nucleus is denoted as n. (B) Details of the lung alveolar epithelial and endothelial barriers. Numerous caveolae (arrows) are seen in the apical and basal plasma membranes of an ATI cell as well as endothelial cell (en) membranes. Caveolae may partake transport of some solutes (e.g., albumin). (C) ATII cells (ATII) are often localised in the comers of alveoli where septal walls branch off. (D) ATII cells are characterised by numerous multilamellar bodies (mlb) which contain components of surfactant. A mitochondrion is denoted as mi.

For a detailed description of the ultrastructure of wood and the cell wall, the reader is referred to the comprehensive texts listed above. Briefly, the cell wall of wood is composed of a number of discernable layers (Figure 2.2). These are divided into the primary (P) and secondary (S) layers the secondary layer is further subdivided into the Sj, S2 and S3 layers. The primary layer is the first to be laid down when the cell is formed and is composed of microfibrils, which have an essentially random orientation that allows for expansion of the cell to occur as cell growth takes place. The secondary layer is subsequently formed, with each of the sub-layers exhibiting different patterns in the way the microfibrils are oriented, as illustrated in Figure 2.2. Of these, the 83 layer occupies the... 

Figure 2.2 A schematic of the ultrastructure of the wood cell wall, showing the middle lamella, the main cell wall layers and the associated microfibrillar orientation.

Dvorak M, Halacka K. 1975. Ultrastructure of liver cells in pig at normal conditions and after administration of small doses of heptachlorine. Folia Morphol 23 71-76. 

Woodcock, C.L.F. (1973) Ultrastructure of inactive chromatin. J. Cell Biol. 59, 368a. 

Cultured hamster trachea exposed to crocidolite showed histologic and ultrastructural evidence of cytotoxicity, regeneration, and fiber transport into the submucosa (Mossman et al., 1977). The full range of cell reactions could be induced by fibrous materials on tissue sections. 

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