Classification of Living Organisms
The living organisms are classified
into different groups and subgroups for convenience to study. Formerly all
living organisms were classified to two major groups on the basis of
characters. These groups are:
1.
Plant Kingdom
2.
Animal
Kingdom
Later on it was realized that all organisms do not fit in either of
these kingdoms. Therefore an attempt was made by Robert Whittaker (1969) who
classified the living organisms into five kingdoms. These five kingdoms of the
living organisms are:
1.
Monera
2.
Protista
3.
Fungi
4.
Plantae
5.
Animalia
Branches of Biology
The bodies of living organisms are
composed of cells that are very complex structures, even more complex than any
of the recently man-made sophisticated machine. The bodies of unicellular
organisms are composed of single cells while those of higher organisms, plants
and animals both. Are composed of more cell. These cells are organized into
tissues that are grouped into organs systems. The living organisms are
different form one another on the basis of structure, function, size shape,
reproduction, body organization, habitat and so many other aspects. Various
disciplines have developed to study these aspects of the living organisms. The
branches of biology such as morphology, anatomy, histology, physiology,
ecology, cytology, taxonomy, genetics, embryology etc. Some other branches are
defined below.
Molecular Biology
Molecular biology is a branch of
biology, which deals with the study of those molecules that are present in the
cells of living organisms.
Microbiology
Microbiology is the study of
microorganisms such as bacteria, fungi, algae etc. the microorganisms are so
small in size, which are not visible to our naked eye. They are studied with
help of microscope.
Environmental Biology
Environmental biology is also called ecology. It
deals with the study of living organisms in relation to their environment.
Different habitats have different environment and different organisms.
Freshwater Biology
Water bodies are of two types.
Freshwater and ocean water, all water bodies other than oceans are called
freshwater. Examples are rivers, streams, canals, lakes, springs, ponds etc.
the study of living organisms in fresh water is called freshwater biology.
Marine Biology
Marine biology deals with study of
those organisms that live in oceans. The habitat of oceans is called marine
habitat and the organisms inhibiting marine habitat are called marine
organisms.
Parasitological
Parasites are living organisms that
get their food from other living organisms. The living organisms’ forms which
parasites get food are called hosts. Parasitological is the branch of biology
which deals with the study of parasite. It includes host-parasite relationship,
life history of parasites, mode of transmission etc.
Social Biology
This is basically a sub-branch of
biology that deals with the study of populations and communities of plants and
animals and their interaction with each other.
Biotechnology
Biotechnology has been defined as the
application of organisms, biological systems or biological process for the
benefit of human beings. Biotechnology provides both products and services.
Example of products is cheese and human insulin while that of the services is
treatment of sewage.
