Motion biological role

The individual HA molecules are present in solutions in random coil conformation and occupy large hydrated volume. This depends on the molecular mass of HA as well as on its concentration When the concentration increases, the motion of the molecular segments becomes more restricted [143]. As an important consequence, such crowded molecular system has significant viscous and elastic properties. The biological role of the HA in vitreous body and in the joint was interpreted according to these rheological properties [144]. 

NMR is a powerful and versatile tool for structural studies of biological RNAs and complexes they form with other nucleic acids, proteins, and small molecules. The goal of these studies is to determine the role that structure and dynamics play in biological function. NMR has the capacity to determine high-resolution structures, as well as to map RNAiligand interfaces at low resolution. Most structures of RNA and RNA-ligand complexes are under 20 KDa in size however, recent advances allow for determination of solution structures of complexes up to 40 kDa. NMR can also probe dynamic motions in RNA on micro- to millisecond time scales. A number of biologically relevant internal motions such as... 

It is interesting that work on the internal motions of the molecules that produce lyotropic mesophases is more advanced. This is mainly because of the importance of the microscopic properties of these systems in solubilization and interfacial problems, problems which are encountered in industry as well as in cell membrane biology. The structural and functional roles of lipid molecules in biomembranes are much discussed investigations of the physicochemical properties of lipid media thus might provide orientations for biological studies. Moreover, the findings on the flexibility of the paraffinic chains in lyotropic mesophases might also be relevant to similar problems in thermotropic mesophases. 

To increase the reliability of assessing the role of the World Ocean in the global carbon cycle, a more detailed description is needed of the production processes in ocean ecosystems. Along with the physical and chemical processes of transformation and motion of carbon in the ocean medium, the biological processes play an important role. In particular, phytoplankton, just like the nutrient elements, assimilates dissolved C02 from saltwater. As a result, an organic substance is formed that partially goes to the nutrient chains of the trophic pyramid of a given basin of the World Ocean and partially descends to bottom sediments. The totality of all the... 

One big issue of the post-Genome Project era is proteomics since proteins play crucial roles in virtually all biological processes such as enzymatic catalysis, coordinated motion, mechanical support, etc. [1]. A protein is a long polymer of amino acids, and folds into a regular structure for its biological function. 

Proton-coupled electron transfer (PCET) reactions play a vital role in a wide range of chemical and biological processes. For example, PCET is required for the conversion of energy in photosynthesis [1] and respiration [2], In particular, the coupling between proton motion and electron transfer is involved in the pumping of protons across biological membranes in photosynthetic reaction centers [1] and in the conduction of electrons in cytochrome c [3]. In addition to biological processes, PCET is also important in electrochemical processes [4, 5] and in solid state materials [6]. 

In Chapter 13, you learned that diffusion is the mixing of gases or liquids resulting from their random motions. Osmosis is the diffusion of solvent particles across a semipermeable membrane from an area of higher solvent concentration to an area of lower solvent concentration. Semipermeable membranes are barriers with tiny pores that allow some but not all kinds of particles to cross. The membranes surrounding all living cells are semipermeable membranes. Osmosis plays an important role in many biological systems such as kidney dialysis and the uptake of nutrients by plants. 

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