Introduction to Biology
Biology is that branch of science which deals with the study of living things (plants or animals). The term biology was
coined by Lamarck and Treviranus. In broad, biology can be defined as- the branch of science which investigates the
origin, structure, function and distribution of life of all forms. Aristotle is considered as the father of biology. Biology
is divided into two main branches, they are – Botany and Zoology.
Botany: - Botany is the branch of biology that deals with the study of plants. Theophrastus is known as father of
botany.
Zoology: - zoology is the branch of biology that deals with the study of animals. The word zoology is made by two
Greek words i.e. 'zoon' means animals and 'logos' means study or knowledge. Aristotle is known as father of zoology.
Scope of Zoology: - there is a vast scope of zoology in different sectors.
1. Scope of zoology in the field of medical science: - humans are suffering from different diseases. Prevention,
treatment and control of emerging diseases are difficult. Zoology provides knowledge of structure, lifecycle
and transmission of particular diseases, which are caused by virus, bacteria, protozoans, helminthes etc.
2. Scope of zoology in the field of Veterinary science: - veterinary science is related with animal husbandry,
practices and proper treatment of animal diseases.
3. Scope of zoology in the field of agriculture: - agricultural science is related with the crop production,
maintenance and supplement of food for growing population. For this knowledge of zoology is helpful.
4. Scope of zoology in the field of industry: - many small scale industries can be established which are based on
animal and animal's products.
5. Scope of zoology in the field of microbiology: - microbiology is related with the study of micro-organisms
mainly bacteria, virus, fungi etc. bacteria and viruses are used to prepare vaccines and antibiotics.
6. Scope of zoology in career development: -
a. Profession: - teacher, lecture, professor, researcher etc.
b. Technical stream: - MBBS, BDS, BPH, BMLT< nursing etc.
c. Vocational stream: animal husbandry, Bee-keeping, poultry etc.
Branches of Zoology:
On the basis of structure and function: -
Morphology: - study of external structure of organisms
Anatomy: - study of internal structure of organisms.
Physiology: - study of life processes of living organisms.
Histology: - study of microscopic structure of tissues.
Cytology: - study of detail structure of cells and their components.
On the basis of specific unit: -
Taxonomy: - study of identification, nomenclature and classification of organisms.
Embryology: - study of stages of early development of embryo.
Genetics: - study of variation and heredity.
Paleontology: - study of fossils.
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Biochemistry: - study of chemical constituents of organisms.
Eugenics: - study of improvement of human race by improving genetic constituents.
Haematology: - study of blood.
Ecology: - study of relationship of organisms with their environment.
Microbiology: - study of micro-organisms.
Biogeography: - study of distribution of living organisms.
Osteology: - study of bones.
Cardiology: - study of heart.
Embryology: - study of formation and development of living things from fertilization to birth.
On the basis of Group of animals: -
Protozoology: - study of protozoans.
Helminthology: - study of helminthes.
Malacology: - study of molluscs.
Herpetology: - study of amphibians and reptiles.
Mammology: - study of mammals.
Anthropology: - study of origin, physical and mental development of human beings.
Nidology: - study of nests of birds.
Virology: - study of virus.
Bacteriology: - study of bacteria.
Parasitology: - study of parasites.
Entomology: - study of insects.
Ichthyology: - study of fishes.
Ornithology: - study of birds.
Limnology: - study of fresh water and their inhabitants.
Apiculture: - farming of honey bees.
Parazoology: - study of sponges.
Cnidology: - study of coelenterates.
Mycology: - study of fungi.
Phycology: - study of algae.
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Biology and its Relation to Other sciences: -
1. Relation of biology with physics: - the combined study of biology and physics is called Bio-physics.
Biological instruments such as microscopes, X-rays, ECG etc. are based on the principles of
physics.
Light induces various effects on living organisms.
Study on the structure and functioning of human eye require knowledge of optics.
Physical techniques such as: electron microscopy, X-ray diffraction, fractionation,
Chromatography etc. have made possible the study of finer details of cellular and sub-
cellular components.
Several camera trapping methods are used to study wild-animals.
2. Relation of biology with chemistry: the combine study of biology and chemistry is called biochemistry.
Body of all living organisms s made up of organic and inorganic compounds.
All the metabolic activities inside the body of living beings involve chemical reactions and
chemical changes.
Genetic materials DNA and RNA are also chemicals.
Enzymes and hormones produced in the body of living organisms are also exclusively
chemicals.
Acid-base equilibrium in a cell maintains the pH of the protoplasm for proper functioning.
Molecules move in and out of the cells by diffusion and osmosis.
3. Relation with Geography:
Distribution of plants and animals vary different geographical factors. e.g. Climate, altitude,
temperature, etc.
4. Relation with Mathematics and Statistics:
Census of wild animals is based on application of mathematical and statistical applications. Such
applications are helpful in data compilation and analysis of living organisms.
5. Relation with Sociology:
Study of human behavior, social relationship and antisocial relationships needs idea of biological
science. For example, investigation on criminals and terrorists requires the study of human nervous
system and study of glands, hormones, etc. It also requires the knowledge of principles of
inheritance, pedigree analysis, etc.
General Approach to understand life process (characters of living beings)
1. Cellularity: Body of all living organisms is made up of cell. Cell s the basic structural and functional
unit of life. Organisms having single cell are called unicellular and are protozoans whereas
organisms having multi-cells are multicellular and are metazoans.
2. Definite shape and size:
The living beings possess definite shape and size except some lower level organisms.
3. Growth:
Living organisms grow from within, using food that they obtain by nutrition.
4. Nutrition:
All the living organisms need food, which is associated and used as a source of energy and materials
for living process such as growth.
5. Respiration:
Respiration is the process of releasing energy by oxidizing the digested food. It involves the process
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of gaseous exchange. Most of the animals have specific organelles for it and however, the plants do
not possess specific organelles.
6. Irritability:
All living organisms have the ability to respond to changes in both the internal and external
environments. Such capacity provides them better chances of survival.
7. Movement:
Movements are distinct in animal than in plants. Animal consists of some special organs for
movements whereas movements in plants are generally shown by the different part instead of the
whole body.
8. Excretion:
Excretion is the removal of metabolic products from the body, all the living organisms' exhibit
excretion process.
9. Reproduction:
All the living organisms have capacity of reproducing young ones like them to maintain the
continuity of life.
10. Aging and Death:
Every organism has definite life span during which it grows, matures and reproduces. With the
increase in age, there is deterioration of structure and function of different tissues, organs and cells,
known as aging. Death is the last event of life span, when body stops functioning. Death is an
irreversible process necessary to continuity of life on earth.
