Introduction to Biology
Introduction to Biology defines biology, enlists its branches and discusses the fields of specialization briefly later in this article.
Biology is one of the natural sciences which deals with the study of living organisms. It is known as study of life. The word biology is derived from Greek words Bios means life and logos mean study or knowledge.
Classification of Living Organism
Formerly living organisms were classified into five kingdoms:
- Kingdom Prokaryotae:
It includes study of almost all prokaryotes, for example bacteria and cyanobacteria.
- Kingdom Protoctista:
It includes all unicellular eukaryotic organisms, which cannot be classified as plant, animal or fungi, for example Paramecium, Chlamydomonas, Plasmodium etc.
- Kingdom Fungi:
It includes multicellular , non-chylophyllus organisms having chitinous cell wall and mycellium, for example Agaricus( mushroom), yeast, etc.
- Kingdom Plantae:
In this kingdom plants are included. The study of plants is called Botany.
- Kingdom Animalia:
In this kingdom animals are included. The study of animals is known as Zoology.
Branches Or Fields Of Specialization:
Some major branches or fields of specialization in biology are as follows:
- Molecular Biology:
It is a new and modern branch of biology in which structure and function of those. Molecules are studied that help in biological processes of living organisms, such as nucleic acid, gene structure, it’s function protein and protein-synthesis. It is the foundation of genetic engineering.
- Micro Biology:
It deals with the study of microorganisms, such as viruses, bacteria, protozoans etc.
- Environment Biology:
It deals with the study of environment and its effect on the body of organisms.
- Marine Biology:
It deals with the study of living organisms which are found in sea water or ocean water. It also deals with the physical and chemical characteristics of their environment.
- Fresh Water:
It deals with the study of life found in fresh water like rivers, lakes, ponds streams etc. with physical and chemical characteristics of living organisms affecting the life.
It deals with the study of the parasitic living organisms, their life cycle, method of disease transmission and interaction with their hosts.
- Human Biology:
It includes all aspects of human life such as anatomy, physiology, health, inheritance, evolution etc.
- Social Biology:
It deals with the study of social activities of certain animals within a population, specially human beings.
It is a very modern and recent branch of biology. It deals with the study of the
- use of data and techniques of engineering; and
- technology for the study and solutions of problems related with living organisms specially in human beings.
It is the soil less or water culture technique, in which terrestrial plants are grown in aerated solution. By this technique vegetables and other plants can be grown. It helps to fulfill the food requirement of people of a particular area. Tomato crop and other vegetables crops are grown in green houses through this technique and satisfactory production is obtained.
Advantages of Hydroponics
By using this technique the crop can be protected from soil diseases and weeds. In dry parts of the world some crops can be grown successfully, for example in green houses tomato and other crops are grown to get production.
The method used in the study biological work is called biological method. It is based on the same principles which are applied in other fields of science. During the research in biology various topics are selected and they are explained in a simple manner which can be easily understood. In order to carryout the research many steps are followed in a systematic way. Scientists make deep observations and collect all information about the work, which have been reported by others. On the basis of these facts and information a scientist presents an experimental statement, called hypothesis. This hypothesis can guide further observations and experimentation.
Applications of Biology:
Immunization i.e. resistance against diseases is carried out by vaccination throughout the world. As a result of this technique polio, small pox, hepatitis and other dangerous diseases have been controlled and rate of infection and death of infants is greatly reduced in the whole world.
Antibiotics are substances which are used to prevent the growth of microorganisms. First antibiotics penicillin was isolated from a fungus, called penicillium notatum. This great work was done by Fleming, flory and chain, they got nobel prize. These antibiotics are widely used to control many diseases, such as T.B., cholera, leprosy, anthrax diseases have been controlled properly in the whole world.
Biology always tries to develop new medicines for the cure and treatment of diseases. In recent days some harmful diseases like aids, cancer are treated with certain chemicals, this technique is called chemotherapy.
Use of radioactive rays (X-rays) are also widely used in the treatment of diseases. This technique is called radiotherapy. This technique is also useful for the diagnosis of diseases. Radiotherapy is usually used for the treatment of cancer, but this technique is very expensive and painful.
- Food Shortage
Due to population increase there is always shortage of food and other necessary things. By the help of modern technology in agriculture and other related fields production of food can be increased.
It is a modern technique in biological science by which duplicate copies of genetics material are produced. It is a method of asexual reproduction. All members produced by cloning are genetically identical. The examples of cloning are regeneration, asexual reproduction in animals and plants. Twins in man and tumors of cancer.In 1997 scientists in Scotland produced a sheep “Dolly” by cloning. This technique is successfully applied in lower mammals.In the process of cloning the nucleus of an egg is removed. Then a nucleus from a cell of fully developed individual is taken and introduced into that egg. After that this changed egg is implanted into the womb of female for complete development. The individual which is developed by this process in quite similar to that individual whose nucleus is used.These points below signify the importance of cloning:
- By cloning method different kinds of human cells can be prepared, such as liver cells, skin cells, blood cells etc. In this way it may be possible to develop body organs of human being and defective organs may be replaced by cloned organs.
- This technique can be used to improve the quality in agriculture and medical sciences.
- Growth hormones, insulin and other substances can be prepared by cloning method.
Levels of Biological Organization
Life is built on chemical foundation and the the life of all living thin organism emerges on the level of cell . The foundation of cell is based on elements. Atoms of different elements unite to form molecules. Living organism usually form extremely large and complex molecules by living matter which is present in their bodies. The molecules of living organism are mostly composed of carbon and provide building blcks of living matter. Mostly living matter of an organism is composed of organic molecules along with inorganic compounds (minerals) are also associated for example Human blood. Simple organic molecules present in living organisms are sugar, glycerol and fatty acids, amino acids, purine and pyramidines. Simple types of cells form tissues. similar tuissues form organs different organs coordinating with each other form system and different systems combine to form a living organism
Cell -> Tissues – >Organs – > Systems -> Individual
Biological Organization can be divided into following levels
Sub Atomic Particles
Particles that make up an atom are called Sub Atomic Particles. For example electron, proton and neutron
The smallest particle of an element retains the property of that element is called Atom. For example Hydrogen Carbon and oxygen has their respective atoms
Combination of of similar and different atoms is called Molecule. For example hydrogen and oxygen atoms combines to form water molecules
A structure with in a cell that performs a specific function is termed as Organelle. For example mitochondia, chloroplast etc.
The smallest structural and functional unit of life is known as Cell. For example a nerve cell
A group of similar cells that performs specific function is called Tissue. For example Nervous tuissues
A structure with in an organism usually compose of several tissue types that forms a functional unit is known as Organ. For example the brain
Two or more organs working together in the execution of a specific body function form Organ System . For example the nervous system
An individual living thing composed of many cells is called Multicuelluar Organism. For example pronghom antelope
A group of very similar inter breeding organisms constitues a Speci. For example pronghom antelope
Members of same species inhabiting the same area are considered as Population. For example Herd of pronghom antelope
Population of several species living and interacting in the same area form Community. For example snake, antelope and hawk
A community with its environment including land water and atmosphere constitute an Eco-System.
The part of earth inhabitied by living organisms, both living and non living components is called Bio Sphere.
This article is part of another article with the title Biology