1-Introduction and role of Science
The history of science is as ancient as the man himself. With the passage of time man learnt from his interaction with the surroundings which later added to his knowledge of science e.g.. when he burnt first time the wood for fire, he basically discovered the process of combustion and he also came to know that wood burns but a stone does not.
Greek philosophers give special interest in science. They took interest in science even before 500 B.C. Greeks were not interested in proving their ideas through experiments. They has a firm belief that life is based on air, water, earth and fire and these four elements make different things when combined in different proportions.
2-Our life and Chemistry
In body of living organisms, many elements were found in different quantities. In them carbon, hydrogen and oxygen have great importance. The human body also constitute these three elements.
These elements combine to form organic compounds such as proteins, carbohydrates and lipids. All these compounds work as building material for the bodies of living organisms e.g meat, pulses, fats , cooking oil, sugar, wheat etc.
Carbon
Carbon is one of the important part of all living things on this planet. Small quantities of carbon are found in the earth's crust as the free element. Carbon is an important element of natural compounds such as natural gas, petroleum and wood etx. Carbon is also present in the food you eat.
Hydrogen
Hydrogen is an important part of water (H2O). It is most common element in the universe, for example the sun is a huge white-hot consisting almost entirely of hydrogen.
Oxygen
Oxygen is a colorless, odorless gas that is slightly soluble in water. Fish and all form of aquatic life rely on this property. It is the major constituent of air. The various organic compounds containing oxygen are glucose, sugar, cellulose, fats, proteins etc.
3-Biochemistry and Biotechnology
Biochemistry is a branch of chemistry which deals with all the chemical reactions taking place in living organisms like plants, animals, bacteria, etc. These chemical reactions can help in the synthesis (anabolism) or breakdown (catabolism) of biological molecules.
The digested food become part of the body due to anabolic reaction while respiration is a simple catabolic reaction.Hi guys if you want to read this book with complete details then download class 9-10 general science book pdf.
Its knowledge has been used to produce a large number of material for the benefits of human beings.The term biotechnology was introduced in 1970. The techniques of biotechnology can be used to alter the genetic make up of microscopic organisms to produce useful materials like enzymes and hormones etc.
4-Human Health
The health is wealth and a great gift from God Almighty. Human health not only depends upon the type of the food we take in but also on the fact whether a man is acquainted of all the phenomenon occurring in its body. Only after having a comprehensive knowledge of all these facts he can be successful to maintain his health.
In this chapter, we shall not only discuss the role of diet to maintain the human health but we shall also try to investigate both intrinsic and extrinsic factors that influence human health and how a man can cope with all these challenges.Guys download class 9th general science book for more details.
5-Diseases, Cause and Prevention
Microorganisms are the living cells which are present all the time around us in the environment such as earth, air, water. All the infectious diseases are caused by microscopic bacteria and viruses. These organisms are of different shapes and sizes.
Nevertheless some disease producing organisms can be seen by human eye, such as intestinal worms etc. The fungus look like planets but they have no roots, stems and leaves and these can also cause many disease.
6-Environment and Natural Resources
Atmosphere is an a envelope of gases. it covers earth from all sides. It is about 200 km thick. The air we breather in is part of the atmosphere. Photosynthesis and burning also occur in presence of air. Atmosphere maintains the temperature of the earth and protects from the harmful radiation coming from the sun.
Pollution means, any change in the air, land or water which have undesired effects on man or other living things on earth or may have such effects in future.
Human activities in the modern industrial world produce a large amount of wastes. Different gases (carbon monoxide, carbon dioxide, sulphur dioxide, oxides of nitrogen etx.), smoke, useless particles and toxic water are released from factories and vehicles.
7-Energy
Energy in the essential part of our lives. Energy is used in our daily life in different forms. We do many tasks from dawn till dark. For this, we have to spend energy. When we get tired after working we fell hungry, we take food which provides us energy.
We cannot do any thing without light. Light is also a form of energy. WE require heat to warm ourselves in winter. Heat is yet another from of energy. In summers, we use fans, refrigerators and air-conditioners for cooling, Besides them, er use many other appliances all of them work with electricity. Electricity provides them energy to run.
All of motorbikes, heavy vehicles, aeroplanes and ships consume fuel, which provides energy. As our usage for machines increases, our requirement of energy also increases. Read all chapters with details after download class 9-10 general science book pdf for free download link given below to post end.
8-Current Electricity
Electricity is very common form of energy, which we use in our homes and work places everyday. It as facilitated the availability of our needs of life. Just turn on the switch and the electricity starts its work.
Electricity is used in four important ways. It causes fans, electric motors and machines to move. It provides light through bulbs, tubes and television. In aloud speaker it is converted into sound and in electric iron, heater and toaster it assumes the form of heat.
9-Basic Electronics
Revolutionary changes have occurred in the world during the last fifty years. Specially, there has been much progress in the field of electronics.Early radio set was so big that two persons could hardly move it. people used to have huge gramophones to enjoy music.
Conquest of space was confined to only imagination. In the beginning, big valves were used in the T.V set. Computer occupies many rooms.But today is the age of microchips. By the use of chips, T.V and computer are reduced in size to such extent that they can be easily shifted from one place to another. Their efficiency has increased to many folds Communication through has increased to many folds.
Communication through satellites has become very common. Transmission from any place can be watched all over the world. this is all by virtue of electronic.You also download general science of class 10th for free.
10-Science and Technology
We had extremely limited resources in the beginning when Pakistan came into being. Most of the things of daily usage had been imported from other countries. In the field of science and technology we were lagging so much that even a bicycle or a fan was not manufactured.
By the grace of God, motor cycles, cars, tractors and even ships are now made in Pakistan.No doubt, it is the age of science and technology, Without the progress in this department, no country can keep the stability of real independence. It always depends on other s for its necessities.
11-Space and Nuclear Programme of Pakistan
Travelling in space, sometimes it had been a dream of man, which has now become a reality, Space travel became possible due to the invention of rocket. In rocket, fuel is burnt with the help of liquid oxygen and the gases produced by it are expelled from its back with very high speed and in reaction rocket moves ahead.
Through artificial satellite, Metrostat, cloud making pictures are taken The meteorologists predict about the weather through the study of these pictures. They also inform people before tiem about cyclone and its speed and direction.I hope you really download class 9-10 general science book pdf for more details.
