The reductionist approach to study of life forms resulted in increasing
use of physico-chemical concepts and techniques. Majority of these
studies employed either surviving tissue model or straightaway cell-
free systems. An explosion of knowledge resulted in molecular biology.
Molecular physiology became almost synonymous with biochemistry
and biophysics. However, it is now being increasingly realised that
neither a purely organismic approach nor a purely reductionistic
molecular approach would reveal the truth about biological processes
or living phenomena. Systems biology makes us believe that all living
phenomena are emergent properties due to interaction among
components of the system under study. Regulatory network of molecules,
supra molecular assemblies, cells, tissues, organisms and indeed,
populations and communities, each create emergent properties. In the
chapters under this unit, major human physiological processes like
digestion, exchange of gases, blood circulation, locomotion and
movement are described in cellular and molecular terms. The last two
chapters point to the coordination and regulation of body events at the
organismic level.
Chapter 16
Digestion and Absorption
Chapter 17
Breathing and Exchange
of Gases
Chapter 18
Body Fluids and
Chapter 19
Excretory Products and
their Elimination
Chapter 20
Locomotion and Movement
Chapter 21
Neural Control and
Chapter 22
Chemical Coordination
and Integration
ALFONSO CORTI, Italian anatomist, was born in 1822. Corti began
his scientific career studying the cardiovascular systems of
reptiles. Later, he turned his attention to the mammalian
auditory system. In 1851, he published a paper describing a
structure located on the basilar membrane of the cochlea
containing hair cells that convert sound vibrations into nerve
impulses, the organ of Corti. He died in the year 1888.
Alfonso Corti
(1822 – 1888)