Biology

When the different methods are used for the good health of the community as a whole in an organised manner it is known as community health or public health.Community health involves following activites :(i) Maintaining sanitation of the environment by supplying safe drinking water and proper disposal of sewage.(ii) Providing methods for prevention and control […]

AddictionSome people start smoking, drinking and taking certain narcotic drugs and feel peace and relief because they are unable to bear tensions and can not solve the problems of their life. This becomes their habit and they are addicted to these.Thus addiction is defined as a physical and mental dependence on any of these and

Forestry is the branch of science which deals with the scientific rearing of forest trees so as to achieve maximum benefit. Thus, forestry is a science by which we study nature, work with nature but do not compete with nature.The word forest had been derived from the Latin word Foris which means outside i.e. the

Population : Population is an assemblage of individuals of the same species, occupying a particular area at a given time.Natality : Natality or birth rate refers to the rate of birth of new individuals in a population per unit time. It is expressed as the loss in the number of individuals per year per thousand

Biotechnology : Biotechnology is the technology which involves biology for the benfit of mankind. The word ‘Biotechnology’ was first time used in the Leeds City Council in United Nations in 1920. It is considered as the most modern branch of biology in which knowledge of biochemistry, microbiology, molecular biology, genetic engineering etc. is used for

Diseases : When the normal functions and physiology of any organ or system do not work well then this is said to be diseased. The healthy person is one who is mentally, physically and socially healthy.How diseases are produced(A) By pathogens : Such as virus, bacteria, mycoplasma, fungi, protozoan, helminthes and other animals attack humans

Our country has a very large number of cattle, buffaloes and other milk producing animals but in comparison to other countries, the milk production is far less. Low production of milk in our country is due to the poor quality of animals, improper nutrition and inadequate diet and negligence in management.Principles of animal breeding(a) Inbreeding

Fertilizers are chemicals used to improve the fertility of the soil and increase crop productivity. ‘Green Revolution’ has come about because of the use of chemical fertilizers. They brought multiplication in crop productivity to several folds. Chemical fertilizer industry needs large scale use of fossil fuels. Large scale use of chemical fertilizers is resulting into

PesticidesPesticides have been used since the evolution and development of agriculture. Pesticide is from Latin word pestis which means the destructive agent or plague. Thus pests are the living creatures which cause economic loss, destruction or injury to agricultural or other household articles.The pests affect the reproductive potentiality of the products over which they feed.The

Plant breeding or crop improvement : Plant breeding is an applied branch of Botany which deals with the improvement of crops and production of new crop varieties which are far superior to the existing varieties in all characters.Aims of Plant Breeding1. To increase the yield of crops.2. To improve the quality of crops3. To develop

Origin of lifeMany theories of “Origin of life” have been propounded by several researchers which are as follows—(1) Special creation theory : God created universe in six days. This theory was published in the ‘Bible’ in 16th century.First day Earth and heaven were createdSecond day Sky was createdThird day Dry earth and plants were madeFourth

Genetics : It is the science of heredity and the principles governing the inheritance of characters from parent to the progeny i.e., offspring is called genetics.Heredity : The process by means of which characters are transmitted from parent to the offspring is called heredity.Mendelism : Mendel’s peas experiment, valid analysis and deduction of laws of

GrowthIt is an autonomic process by which the synthesis of protoplasm results in the increase in size and weight. It is a basic property of all of living beings. The anabolic activities are far more than the catabolic activities. The cells of every living being undergo wear and tear. In some animals, some cells and

Female reproductive cyclesMammals are exclusively sexually breeder. The reproduction depends upon certain changes in reproductive organs and behaviour. The changes mainly consists of the sexual cycles (especially the female). There are two types of cycles exhibited by the mammals—(1) Menstrual cycle : Normally this cycle repeats after every 28 days. After 28 days the ova

Reproduction : Reproduction is the process by which an organism produces the same species.Types of reproduction :(a) Asexual reproduction(b) Sexual reproduction(A) Asexual reproduction : This involves the production of animals without any fertilization and zygote formation. This is of following types :(i) Binary fission : Amoeba, Euglena, Paramecium, Vorticella, Aurelia, etc.(ii) Multiple fission : Plasmodium,