Principles of Biology

Biology can be a very complex science, and its principles are not always easy to define. Defining life itself is not easy, either, and there has been no totally satisfactory definition of life. As more and more is known about subcellular structures that prey on living things (e.g., prions and viruses), it is clear that the demarcation between living and nonliving things is not well defined. 

Living things are not passive players. All living things actively attempt to control their environments to better suit them. If that is impossible, they either become dormant until environmental conditions change or else they die. Sometimes (e.g., the case of the seeds) it is difficult to distinguish between dormancy and death. So, perhaps it is easier to define life as anything that isn t dead. See Section 6.23 for further explanation. 

Life is redundant. There are many redundant features incorporated into living things. This makes life very robust. Because of redundant structures and processes, living things will 

FIGURE 5.0.1 The BU is at least partly defined by and helps to define the snrrounding physical, chemical, and biological environment. 

Coexistence of species requires that each adapts to a different ecological niche. Otherwise their competition would be detrimental to one or both, to the extent of disappearance. See Section 5.4. 

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Using the principles of biological olfaction, electronic nose systems contain arrays of different types of cross-reactive vapor-sensitive sensors. While it is difficult to discriminate analytes entirely by their responses to a single type of sensor, using an array of sensors yields response patterns that can readily distinguish many different vapors. Ideally, the response mechanisms of the sensors are highly varied and encompass both physical and chemical phenomena1. 

Varela, F. J. (1979). Principles of Biological Autonomy. North Holland/Elsevier. 

Danilevsky, N.N., Ivanov, L.S., Kautish, I. and Veriati-Marinescu, F. (1979). Fisheries potential resources (In Russian). In The Principles of Biological Productivity of the Black Sea (K.S. Tracheva and Yu.K. Benko, eds), pp.291-299. Naukova Dumka, Kiev. 

Karzinkin, G.S. (1952). The Principles of Biological Productivity of Water Bodies (In Russian). Pishchepromizdat, Moscow, 372 pp. 

Lewalter J, Korallus U, Harzdorf C, et al. 1985. Chromium bond detection in isolated erythrocytes A new principle of biological monitoring of exposure to hexavalent chromium. Int Arch Occup Environ Health 55 305-318. 

Spencer,H. 1884. The Principles of Biology. D. Appleton Co., New York. Spiegelman, S. 1967. An in vitro analysis of a replicating molecule. American Scientist, 55, 3-68. 

In 1954, the book by Professor B.N. Tarusov "Principles of Biological Effects of Radioactive Emissions" was published [1] the book made a great impression on me. The author, an outstanding Soviet biophysicist. Head of the Biophysics Department at the Faculty of Biology of the Moscow State University, put forward a hypothesis that the development of radiation-induced disease is associated with the induction of ramified chain reaction of oxidation of fats of cellular shells (membranes), the oxidation products are very toxic for the cell. 

Despite their favourable properties, peptide-based drugs are under-represented in the pharmaceutical market. This discrimination is usually due to their poor bioavailability, which sometimes necessitates non-oral administration or even special medical devices such as inhalers. Another related major disadvantage of peptides is their low metabolic stability due to proteolytic degradation, hi addition, costs of goods for the drug substance are sometimes tremendous. Therefore, there is considerable interest to transform the active principle of biologically active peptides into small molecules with improved pharmacokinetic properties, hi this chapter, we present an overview of... 

Lipid bilayers are formed by many amphiphilic molecules in the presence of water. Their interest derives not only from the fact that they are a major, if not the only, organizing principle of biological membranes (1), but also because they tend to form closed (usually) spherical structures (liposomes or lipid bilayer vesicles) in which inner and outer aqueous spaces are separated by the lipid bilayers (2) which thereby provides a means of encapsulation (3, 4). 

Alon U. An Introduction to Systems Biology Design Principles of Biological Circuits. 2006. Chapman Hall/CRC Press, Boca Raton, FL. 

V.P. Skulachev, Mitochondria in the programmed death phenomena a principle of biology It s better to die than to be wrong . lUBMB Life, 49 (2000) 365-377. 

Drost-Hansen, W. (1970). Role of water structure in various membrane systems. In Physical Principles of Biological Membranes (Snell, Wolken, Iverson, Lamb, eds.), pp. 243-258, Gordon and Breach, New York. 

Enormous effort has been expended attempting to fathom the operating principles of biological machines [10, 11]. How do muscles contract How do bacteria swim Biologists and biochemists have put forward crude models that attempt to show, in a superficial way, what is happening if one were to examine through a microscope a muscle contraction or the propulsion of a... 

It is not possible to provide here a complete survey of all metabolic processes including gaseous molecules. Thus, a few examples will be selected for a broader description of the functional principles of biological systems including gaseous compounds either as substrates or as products. As photosynthesis appears to be the indispensible prerequisite for the evolution and sustenance of the present stage of life this process will represent the main part of the following paper. 

We do not know for certain whether or not the Greeks knew of the advantage. Writings attributed to Hippocrates are rich in allusions to what we would interpret today as population genetics, and they contain many astute observations that imply general philosophical principles of biology. In principle, the... 

The 19th century produced the application of true scientific principles to man s search for drugs. Analytical methods were developed to determine the chemical and physical purity of compounds, and the principles of biological assay were introduced. With the contributions of Pasteur and Ehrlich, the foundations were laid for chemotherapy. Sem-... 

Mendel s 1866 paper on plant hybridization proposed a numerical, integral pattern ( N) for the distribution of hereditary qualities, a view contrasting strongly with Darwin s non-quantitative, infinitesimal variations. Mendel, in his paper, did not explore the nature of possible particle units that might account for his laws. Others before him, Maupertuis, Buffon, Diderot, and Herbert Spencer in his Principles of Biology of 1864 had propounded ideas of particulate inheritance. 

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