Biology Reference
In-Depth Information
alive. No matter how thin the dividing line is, there is qualitative jump between
a living and a nonliving system (cf. Mahner & Bunge, 1997). Therefore, much
of biology and systems biology starts with cell biology.
In a classical paper, Mayr argued that “the word biology is a label for
two largely separate fields which differ greatly in methods, Fragestellung and
basic concepts which may be designated functional biology and evolutionary
biology” (Mayr, 1961). This topic sets out to highlight the systems biological
approach of functional biology, and, as a consequence, comparatively little atten-
tion is given to evolutionary biology (but see Chapter 5). In other words, the
topic mainly focuses on the living processes occurring in extant life forms. How-
ever, the quest for minimal life, i.e. the smallest unit of life among autonomous
cells, is an important and interesting experimental and conceptual issue within
systems biology (see chapters by Westerhoff & Kell; Keller; Bechtel). In this
respect, also the transition from inanimate to animate matter, i.e. the origin of
life, is a topic that is highly relevant to systems biology.
Most often, in the literature as well in as in biology textbooks, life is described
in terms of a list of purported characteristics (e.g. Koshland, 2002; Duve de,
1991). Such lists differ among each other with respect to the number and the
nature of the characteristics. It seems always possible to find exceptions, i.e.
systems that appear to be living but do not exhibit all of the characteristics
mentioned in the list. These lists also invariably display appreciable overlap and
it seems very well possible to distill a 'consensus' list of the essential features
of the living state. Giving an unambiguous definition of life, however, is a much
more difficult task and has proven to be an enigmatic problem. Most authors
refrain from attempting this and confine themselves to presenting a list of vital
characteristics. In this topic, the enigmatic problem of the question 'What is
life and how did it originate' is addressed by Hofmeyr (Chapter 10), Moreno
(Chapter 11), and Bechtel (Chapter 12).
5. AIM AND OVERVIEW OF THE BOOK
This topic attempts to provide discussion material that should lead to a better
definition of the ways in which systems biology should be carried out. Thus
it should provide philosophical foundations to this new discipline. The topic is
divided into this introductory chapter, three major sections and a concluding
Chapter 14. The sections are each dedicated to a major theme. The first sets the
scene in terms of describing systems biology research programs (Chapters 2-5).
The second discusses theory and models (Chapters 6-9). The third of these
sections deals with organization in biological systems (Chapters 10-13). All
authors except Callebaut and Krohs presented a first form of their contribution
