Organization structure and function

Toxicologic research (Chapter 8) on the effects of ozone in laboratory animals has demonstrated that exposure to airborne ozone at less than 1 ppm for a few hours produces numerous changes in cell and organ structure and function. The lowest concentrations that produce these changes differ somewhat among different species of laboratory animals and with the effect under observation. However, several functional and morphologic indexes of response to ozone are altered with exposures to concentrations of about 0.2-0.5 ppm over periods ranging from a few minutes to several weeks. 

In the living organism structural and functional proteins are continuously synthesized and degraded within hours to days (Mitch and Goldberg, 1996). 

Nusrat A, Chen JA, Foley CS, et al. The coiled-coil domain of occludin can act to organize structural and functional elements of the epithelial tight junction. J Biol Chem 2000 275 29,816-29,822. 

Recently, the author advocated the application of the systems approach in the analysis and synthesis of a biotechnological process ( 1). The hierarchy of a biological system involves structural, functional, descriptive, control and dynamic organization. Structural and functional hierarchies of a biotechnological process are depicted in Tables I and II. In Table II a compartmental level is omitted. This is possible as long as the translocation of substances between organelles and cytoplasm is not important. The scheme of functions should be understood in both directions,... 

Wiltz, D., et al. Extracellular Matrix Organization, Structure, and Function. Calcific Aortic Valve Disease (2013)... 

Physiological effects of air pollution are deperrdent on dosage, the ability of the exposed organism to metabolize and excrete the pollution, and the type of pollutant. Many pollutants affect the futretiotring of the respiratory tract some change the structure and function of molecules others can enter the nucleus and turn getres otr or off atrd some cause chromosomal aberrations or mutations that result in cancer. 

Much of our knowledge of the structure and function of endocytic receptors is based on the analysis of the LDL receptor gene family. Member s of this extended gene family can be found in a variety of species ranging from roundworms to insects, to vertebrates. Ten receptors exist in mammalian organisms, all of which share common structural motifs required for receptor-mediated... 

Disturbances that increase water scarcity promote the physical uniformity of river systems and the decrease of biological diversity in streams and rivers. The structure and functioning of heavily impacted river systems become mutually and strikingly similar, irrespective of the river s origin and the climate. The more intense and persistent the disturbance, the greater is the resemblance. On the other hand, river organisms use resources most efficiently in spatially heterogeneous chaimels, and under moderate disturbance frequencies, rather than in steady conditions, to which they are not adapted. 

The state of communities and ecosystems can be described according to both structural and functional parameters (see Chapter 14 in Walker et al. 2000). Functional analyses include the measurement of nutrient cycling, turnover of organic residues, energy flow, and niche metrics. Structural analyses include the assessment of species present, their population densities, and their genetic composition. 

The Langmuir-Blodgett (LB) technique was successfully applied for the deposition of thin protein layers (Langmuir and Schaefer 1938, Tiede 1985, Lvov et al. 1991). LB organization of protein molecules in film not only preserved the structure and functionality of the molecules, but also resulted in the appearance of new, useful properties, such as enhanced thermal stability (Nicolini et al. 1993 Erokhin et al. 1995). 

These may be produced by grouping together multiple cell models to form virtual tissue segments, or even the whole organ. The validity of such multi-cellular constructs crucially depends on whether or not they take into account the heart s fine architecture, as cardiac structure and function are tightly interrelated. 

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