FST -1

20th Part

Q.  Deliberate upon the recent technological developments in the energy sector giving appropriate examples.

A.  The energy sources available in India are fossil fuels (like lignite, coal, and petroleum) the sun, wind, geothermal energy (for example, hot springs) water (hydro-electric power). The demand for energy doubles every 14 years and is taken as one of the indicators of development of a country. Many technological developments are shaping the energy sector in a new way by using technology to harness the energy of resources available which was not earlier possible. Some of these sources of energy are- 

Solar Energy - With the help of photocells, solar energy is harnessed. Solar energy is used directly to give us hot water during winter or run a refrigerator. It is also used for heating rooms in colder regions. Photocells are used to produce electricity for driving vehicles and illumination of streets. In a desert-like Rajasthan, the earth's surface receives solar energy at the rate of 200 watts per square meter per hour. Since this feature of using solar energy is that it can be generated where needed. Solar cookers are being used in many homes to cook food now. 

Wind Energy - Like solar energy, wind flow can also be harnessed to obtain mechanical energy for fetching water from the wells or from rivers. Once the windmill is turning due to the force of the wind, it may as well run a generator to get electrical energy. In the coastal and hilly regions, where the wind blows at high speed, a windmill can be used for the supply of electricity to a small town.

Wave and tidal energy -  Waves and tides are another sources of energy which is perpetual and can be converted into electric energy, particularly where sea water can move into a narrow cut, such as is provided naturally where rivers flow into the sea. The energy carried is used in India's hilly regions when a wheel with pedals can be made to turn when it is put in a fast-flowing stream. Flour mills of small size built on this principle were used in Kashmir. Here a natural or artificial water fall is made to turn turbine blades which when rotates generates electricity. Large hydroelectric power stations work on the same principle for generating electricity.

Geothermal Energy -

Hot water and superheated steam of hot springs are a natural phenomenon and is used to generate electricity. In our country, there arc 46 hydrothermal areas where the temperature of the spring water exceeds 150°C. These hot springs can be used to generate electricity for heating homes, or glass-houses to prow vegetables.

Atomic energy -

In view of the fast depletion of our non-renewable resources like coal and petroleum, and because of pollution which power stations burning coal causes efforts are underway to construct Atomic reactors to produce electricity. With the energy of the atom controlled in nuclear fission reaction, the energy and heat produced during the bombardment of atoms of U235 is channelized for electricity generation. The device used for this purpose is called an atomic reactor. Nuclear reactors produce heat, which is commonly used to raise steam, which rotates turbines and thus generates electric power. It is estimated that 1 kg of natural uranium generates energy equal to that produced by 35,000 kg of coal. Thus the production of energy from nuclear fuel like uranium is efficient, and since great loads of coal or diesel are not consumed daily this energy is convenient. 

Biogas -

Cattle dung for the production of biogas which is used for cooking. Water weeds like water hyacinth, water lettuce, Salvinia, hydrilla, duck weeds, and algae are found to be a useful supplement to cattle dung. Biogas can be used not only as cooking gas, but it can also be used to raise steam, which can be used for running engines or machines in the factories or for running turbines to generate electricity. It has been found that large biogas plants can supply the needs of a number of families or even small villages. What is left over after generating the gas, can be used as manure. Hence this is also an economical way of getting more energy. Great efforts are being made to install tens of thousands of biogas plants in rural areas as it is one of the efficient ways of generating electricity.

Q.  ‘Science and technology do not exist independent of the society, its culture and value system. They are part of the socio-economic and political framework of a given society’. Analyze this statement by giving suitable examples. 

A.   As science and technology provide all the necessities as well as many of the ideas that hold our society together, society itself provides the environment and the atmosphere for science and technology to either grow fast or stagnate or even decay. Science and technology do not exist independent of the society, its culture and the value system. They are a part of the socio-economic and political framework of a given society. The motivation for the practical application of science and, hence, its growth and use comes from the economic needs of society. The economic planning and policy of a society determine its social programmes and the purposes and goals of society's production activity, which in turn provides the incentive for scientific growth. However, answers to questions like what kind of economic policy will be pursued, whether the social programmes will be implemented, and to what extent, depends on the political and social organization of a society. Thus, science and technology can be more directly influenced by the general policies and social structure of a society. For example, when economic growth is purely determined by market demands, artificial demands for goods are created by advertising, even though there is no pressing need for them. Ideas of people are sought to be molded by propaganda carried on by radio or television or even by education. The competition to produce more goods, increase profits or the desire to provide fancy goods to an influential section of population results in one kind of development of science and technology. On the other hand, if society desires and plans to improve rural life or give priority to public health or provide a certain level of nutrition to all citizens, the tasks and consequent development of science and technology should follow a different path. Still another example is the question of spending money on a weapon of offense or defense that naturally affects science and technology. It is known that the world today is annually spending Rs. 15 lakh crores on weapons and their development. This not only takes away money needed to feed, clothe or provide health and shelter to people, but it also prevents the development of science and technology for constructive purposes. We can conclude that science and technology are part and parcel of a larger social system, whose other components are industry, agriculture, trade, distribution of goods, communication, education, government and administration etc. Science and technology cannot be advanced by viewing them in isolation. The whole social, economic and political system will have to work in unison so that all-round advancement can take place. In the end, we can say that science influences the entire social edifice, the material as well as ideological, and in turn science itself is influenced by society and its objectives.

            Before any project is taken up, its positive, as well as negative aspects, the effect it will have on human beings and the environment, must be properly evaluated. "Social good" must have primacy in the overall planning and the use to which science and

technology is put.

Q.  (a) Describe the various ways by which the human body battles against germs.

(b) How does vaccination protect us from disease?       

A.  First of all the skin and the mucous membranes of our body help us to keep germs out of our body. There are glands in the skin which produces oily substances to provide a protective cover to the surface of the skin. Perspiration helps us to eliminate certain waste and germs out of the skin. Perspiration also contains a special chemical known as lysozyme which destroys the germs. lysozyme is also found in tears, saliva, nasal secretion and tissue fluids. Many types of germs which happens to reach our stomach are destroyed by strongly acidic stomach juices. 

         Apart from this, our body has a potent defence system called the immune system and it is spread throughout the body. The immune system is in the form of special cells called white blood cells which circulate throughout the body along with blood. The white blood cell are of different types and fight the invader germs in variety of ways. During any kind of infection, there is an automatic increase in WBC,  and they are produced in large numbers. 

       When germs attack over the body, special types of WBC migrate to the infected site and destroy the invader germs by engulfing them. These cells are called engulfing cells. Another kind of WBC produces a chemical weapon called antibodies that attack toxic substances to make them ineffective. These antibodies also tag the invading germs so that they can be easily recognized by engulfing cells. Yet another type of WBC work as killer cells and directly destroy the invader or the infected body cell. Thus the whole body goes into action mode as soon as disease germs enter the body .

            Vaccination is a process of inducing artificial immunization. Through vaccination, antibodies are artificially inserted into the weak body, where the body is fighting invading germs and the immune system has weakened. Thus through vaccination antibodies are entered into the body that to strengthen the defense mechanism and produce WBC to combat that particular infection. In this way, vaccination helps in strengthening the immune system and fighting the invading germs or the infection. 

Q.  Name one disease each spread by air, water, food, and contact.  
A.  Air - Common cold, Leprosy, Measles

      Water - Cholera , Typhoid, Diarrhoea, Dysentry

      Food - Typhoid, Bacillary dysentery

      Contact - Syphilis, Gonorrhea 

Q.  What are infectious diseases? Name any two diseases caused by bacteria and give their symptoms and preventions also.    

A. Infectious diseases are those diseases that are caused by germs or microbes and which move from one person to another. Microbes are minute organisms that cannot be seen with the naked eye. Some of them can be seen with the help of an ordinary microscope while others are so small that they can be seen under very special microscopes. Some of the infectious diseases are also caused by worms.

Typhoid is spread through bacteria which is present on contaminated food or is served by a person who hasn't washed his hands after defecation or urination etc

1.  Typhoid: An infection caused by bacteria. It is caused mostly due to contaminated water and outside food. 

Symptoms:  Fever, weakness, vomiting, etc.

Prevention: By properly washing hands before and after eating, drinking clean water, avoid eating spoil food exposed to flies or contaminated food served by an infected person or cooked in unhygienic place.

2.  Dysentery: An intestinal infection affecting both children and adults. It is caused by bacteria. 

Symptoms: Severe pain in the abdomen, loose motions, weakness, and fever.

Prevention: By properly washing hands before and after eating, drinking clean water, avoid eating spoil food exposed to flies or contaminated food served by an infected person or cooked in unhygienic place.By maintaining personal hygiene.

3. Leprosy: It is an infection caused by bacteria. It is spread from person to person by touch in most cases.

Symptoms: Inflammation, itching Scars, loss of appendages of hands, etc.

Prevention: Since it is infectious, maintain a distance from infected person & personal hygiene. 

Q.  List various modes of spread of diseases. Discuss any two of these modes along with methods of prevention.    

A.  The different modes of spread of diseases are air water food contact insects and other carriers.

Air 

A number of diseases are caused due to bacteria and viruses that are carried in the air. When an infected person sneezes or coughs, there is a noticeable spray of drops. These tiny droplets of liquid contain germs that can remain afloat in the air for a very long time. If another person is standing by he is likely to breathe in quite a lot of these germs and thus get infected. One sick person, therefore, can infect a lot of others. Common cold, leprosy spread through this manner. These diseases spread easily in damp closed spaces. 

Prevention

Air can be disinfected by mechanical means, ultraviolet radiation, chemical vapour or special filters for air coming into rooms. In offices or residential places, ventilation helps to replace polluted air. The quality of incoming air with regard to temperature, humidity, and purity is also an integral part of the ventilation which ultimately provides an environment for comfort and is free from the risk of infection. Green plants also purify air. Green Belt area should be increased to enhance the self-cleaning power of the environment. Green plants around the residential complexes, offices should be increased as they improve the quality of air by purifying it. 

Water

Diseases like Cholera, typhoid, dysentery spread through water. Germs of these diseases multiply in the gut of the infected person and come out in the faeces. Eggs of worms also come out in the faeces.  If the infected faeces and Urine are passed in an open field, germs or eggs are carried to the source of local water supply such as pounds or rivers. Bathing or washing of utensils in such water or drinking it, can infect other people. Sometimes in slum areas, the toilets are too close to hand pumps and thus drinking water becomes a source of disease. People living in such areas are the ones who suffer most from the water borne diseases. The other reason for the spread of the diseases is negligence in personal hygiene by infected person. If the infected person do not wash their hands carefully after defecation or urination, the hands are likely to carry germs which will be transferred to other objects like food utensils or furniture. When these objects are touched by a healthy person the germs find their way to him.

Precaution

Drinking water must be free of disease-causing agents or harmful chemicals. Proper disposal of human excreta is an essential requirement of Community Health. At home drinking water can be made safe by filtration and boiling. Filtration removes most of the suspended impurities, while disease-causing microbes are killed by boiling. Also, handpumps should be deep enough so that they can draw naturally filtered water.

Q.  Explain the term artificial intelligence. 

A. Normal computers can perform complicated calculations and solve logical problems only solve logical problems only because they are given a detailed program for action for action. Artificial intelligence means computers which can firstly learn the rules of any specific Signal Processing, and then apply them to solve the related problem on their own. These computers having artificial intelligence can do specific jobs like interpreting data, taking  photographs of the earth taken from spacecraft to determine the position of airfields missile launching sites or  Ships moving on the high seas. Artificial intelligence is the ability of a computer system to produce an output that seems to come from an intelligent human being.

Q.  Methodology of reward and punishment helps in learning process. Discuss. 

A.      Reward and punishment is a form of learning. For example, if one has a pet puppy and he wants to train it to sit down. the puppy would not understand the words sit down as the puppy doesn't understand the language, but if while giving the command you physically make him sit and give him a biscuit then on the experience being repeated few times the puppy will learn to obey the command. Thus the puppy will associate the sound of the command to sit, with the reward of a biscuit. After training, the puppy will sit down as soon as he is given the command sit, even if he is not given any reward. In some situations, the punishment would also lead to the same result.

We learn a lot of things through the reward and punishment method for example when a baby is hungry he cries, which attracts the attention of the mother and the baby is given milk. The child will soon learn the trick. Similarly, in school when a student in the maths class solve a problem correctly, He receives praise by the teacher. Next time he will approach other maths problems with greater zeal so as to get the teachers approval and praise.  The principle of reward and punishment is used in the educational field extensively because teachers in school are constantly encouraging or rewarding good performance or good actions and discouraging or punishing poor performance of activities. The same principle is used in the society in public organizations, bonus for productivity in a factory or cut in wages if there is low production are examples of reward and punishment. A similar method is employed by the traffic police as it imposed fine on motorists if they cross a red line, or by parents who do not allow the children to watch television if the homework is not done are other such examples.

Q.  Use examples to explain the roles of memory, reasoning, analysis, and synthesis in the learning process. 

Q.  Cognitive learning

A. Four things play the main role in learning, these are the memory, reasoning, analysis, and synthesis.

Memory - memory is very important because it is the process by which we hold information in our mind, but mear memory is not enough. One may memorize whole books and yet couldn't understand anything. The information carried by memory has to be subjected to reasoning to understand fully.

Reasoning - reasoning allows us to see the connection between different bits of information or different ideas and concepts. For example, the rising of the sun and daylight, for the gathering of clouds and rain that might follow the cause and effect relationship also explained in terms of reasoning. When we apply reasoning we can make more sense of the information given to us and reach some conclusions. For example, the various facts about murder, on the basis of reasoning and analysis, may indicate exactly how it could have taken place, or who did it. 

Analysis - analysis is thus considered to be a higher mental activity than memory or reasoning.  However ultimately information from many areas of analysis is to be combined to make a whole picture. The process is first to take things apart: reason and analyze and then to put them together, or synthesize, in order to fully understand something. 

‌Synthesis -  synthesis can be called a higher level of mental activity then even analysis. This doesn't mean that all this process takes place separately or even one after another. In the mind, reasoning, analysis and synthesis go on forward and backward until some conclusion or understanding emerges. This kind of learning which is fairly complicated and involved thought process is called cognitive learning.  Every student experiences it, and all of us acquire knowledge about all our lives in this cognitive learning manner.