BIOLOGY
biology, study of living things and their vital processes. The field deals with all the
physicochemical aspects of life. The modern tendency toward cross-disciplinary
research and the unification of scientific knowledge and investigation from different
fields has resulted in significant overlap of the field of biology with other
scientific disciplines. Modern principles of other fields—chemistry, medicine,
and physics, for example—are integrated with those of biology in areas such
as biochemistry, biomedicine, and biophysics.
In his theory of natural selection, which is discussed in greater detail later, Charles
Darwin suggested that “survival of the fittest” was the basis for organic evolution (the
change of living things with time). Evolution itself is a biological phenomenon common
to all living things, even though it has led to their differences. Evidence to support the
theory of evolution has come primarily from the fossil record, from comparative studies
of structure and function, from studies of embryological development, and from studies
of DNA and RNA (ribonucleic acid).biology, Study of living things and their vital
processes.
Branches of biology
An extremely broad subject, biology is divided into branches. The current approach is
based on the levels of biological organization involved (e.g., molecules, cells, individuals,
populations) and on the specific topic under investigation (e.g., structure and function,
growth and development). According to this scheme, biology’s main subdivisions
include morphology, physiology, taxonomy, embryology, genetics, and ecology, each of
which can be further subdivided. Alternatively, biology can be divided into fields
especially concerned with one type of living thing—for
example, botany (plants), zoology (animals), ornithology (birds), entomology (insects),
mycology (fungi), microbiology (microorganisms), and bacteriology (bacteria). See
also biochemistry; molecular biology.
Morphology, in biology, the study of the size, shape, and structure of animals, plants,
and microorganisms and of the relationships of their constituent parts. The term refers
to the general aspects of biological form and arrangement of the parts of a plant or an
animal.
Taxonomy is a science that deals with naming, describing and classification of all living
organisms including plants.
Physiology is the study of normal function within living creatures. It is a sub-section of
biology, covering a range of topics that include organs, anatomy, and biological
compounds, among others.
Ecology is the study of the relationships between living organisms, including humans,
and their physical environment; it seeks to understand the vital connections between
plants and animals and the world around them.
Genetics is the branch of biology concerned with the study of inheritance, including the
interplay of genes, DNA variation and their interactions with environmental factors.
Biochemistry explores chemical processes related to living organisms. It is a laboratory-
based science combining biology and chemistry. Biochemists study the structure,
composition, and chemical reactions of substances in living systems and, in turn, their
functions and ways to control them.
