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NOTES ON "LIFE PROCESS" BY-NAGRAJ SIR

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 NOTES ON "LIFE PROCESS" BY-NAGRAJ SIR Basic life processes are : Nutrition, Respiration, Transportation, Excretion, Reproduction etc. Life Processes require energy which is provided by nutrition. Nutrition:  The process by which an organism takes food and utilizes it, is called nutrition. Need for Nutrition:  Organisms need the energy to perform various activities. The energy is supplied by the nutrients. Organisms need various raw materials for growth and repair. These raw materials are provided by nutrients. Nutrients:  Materials which provide nutrition to organisms are called nutrients. Carbohydrates, proteins and fats are the main nutrients and are called macronutrients. Minerals and vitamins are required in small amounts and hence are called micronutrients. Modes of Nutrition 1. Autotrophic Nutrition. 2. Heterotrophic Nutrition. Modes of Nutrition Autotrophic :- Kind of nutrition in which organisms can synthesize their own food Eg. Green Plants Heterotrophic:- ...
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short notes "Management of Natural Resources" by Nagraj Sir

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short notes "Management of Natural Resources" by Nagraj Sir Natural Resources – Resources provided to us by nature soil, air, water, forests, wildlife, coal and petroleum are used by man for his survival. Types of Resources  : (a) Exhaustible : present in limited quantity e.g. coal petroleum. (b) Inexhaustible : present in unlimited quantity e.g. air, water. Reduce:  This means that you use less. You save electricity by switching off unnecessary lights and fans. You save water by repairing leaky taps. You do not waste food. Recycle:  This means that you collect plastic, paper, glass and metal items and recycle these materials to make required things instead of synthesising or extracting fresh plastic, paper, glass or metal. Reuse:  This is actually even better than recycling because the process of recycling uses some energy. In the ‘reuse’ strategy, you simply use things again and again. Instead of throwing away used envelopes, you can rever...
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NOTES ON OUR ENVIRONMENT BY Nagraj Sharma

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NOTES ON OUR ENVIRONMENT ( Nagraj Sharma ) Environment :  The physical, chemical and ‘ biological conditions of the region in which an organism lives is called its Environment. It includes air, light, soil, temperature, water and the presence or absence of other organisms, i.e., the conditions for development or growth. Ecosystem :  A community of organisms, interacting with each other, plus the environment in which they live and with which they also interact. The examples of ecosystem are : a pond ; a desert; a forest; a lake ; a river ; a mountain ; the sea. All the above ecosystems are made-up of two main components. Food Chain :-   A food chain is a simple representation of transfer of energy from the sun to different biotic components of an ecosystem. When an animal takes food, this energy is supplied to the next level. and the process goes on.  Food Web:-    In any ecosystem, there can be many food chains which are interlinke...
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short notes on "HEREDITY " by Nagraj Sir

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short notes on "HEREDITY" by Nagraj Sir Introduction Heredity is the passing of traits from parents/ancestors to offspring. Heredity occurs through inheritance of genes. Biological inheritance is what is related to heredity. Study of heredity is termed as Genetics. Inheritance from a previous generation provides a common basic body design and few changes in it for the next generation. A trait that is genetically passed down from one generation to another is termed as ‘Inherited trait’. Some of the common examples of inherited traits are hair colour (Black, brown, red etc.), eye colour(Black, brown, blue), height (tall, short), Ear lobes (free, attached)  Variation :  It means the differences in the characters or traits among the individuals of a species. Variations occur during reproduction both because of error in DNA copying and as a result of sexual reproduction. Variations contribute to evolution. Causes of variations: 1.       ...
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