title: Gravitational effects on biological systems.
abstract: The possible effects of the earth's gravitational field on biological systems have been studied from a quantitative point of view, focusing the attention to  a very simple system, a solution containing proteins, which biochemists might use in experiments. Gravity has been compared with other forces which are known to influence protein activity, including thermic agitation, weak electrostatic interactions, Van der Waals forces and viscous dissipation. Comparisons have been described in terms of the energy of the interaction per mole, referring to some physically simple cases and substances of biological interest. From this study it is evident that the earth's gravitational energy should be taken into account when considering the chemical behaviour of solutions containing substances that have high molecular weight, such as a typical protein, since its value is comparable to other weak interactions. Moreover, since solutions represent the basis of much more complex biological processes taking place inside cells, the influence of gravity should extend also to cellular biochemical behaviour, especially in presence of altered gravity, both in microgravity (such as on satellites orbiting around the earth), and in macrogravity (such as in a centrifugating biological system).
authors.affiliation: Dipartimento di Energetica "Sergio Stecco", Universita di Firenze, Italy. boncinel@sergio.de.unifi.it
authors.forename: P
authors.initials: P
authors.lastname: Boncinelli
authors.forename: P
authors.initials: P
authors.lastname: Vanni
mesh_terms: D055592:Biophysical Phenomena; D001703:Biophysics; D002468:Cell Physiological Phenomena; D006112:Gravitation; D008954:Models, Biological; D011506:Proteins / Q000737:chemistry
chemical_list: D011506:Proteins