Main Idea Identification

सध्या बाजारात जननिक अभियांत्रिकीची अनेक उत्पादने आढळून येतात. उदा. इंटरफेरॉन, मानवाचे वृद्धीसंप्रेरक आणि मानवीय इन्स्युलिन. सन 1982 साली पुन:संयोजी जिवाणूने बनविलेले मानवीय इन्स्युलिन बाजारात विक्रीस आले. पूर्वी ही सर्व प्रथिने प्राण्यांच्या पेशीपासून शुद्ध केली जात होती. परंतु मानवावरील ही स्वरूपे त्यावेळी फार कमी प्रमाणात उपलब्ध होती. 1982 च्या पूर्वी मधुमेहात उपयोगात येणारी सर्व इन्स्युलिन केवळ गुरांच्या बोव्हीन व डुकरांच्या स्वादुपिंडापासून शुद्ध केली जात होती. ही सर्व इन्स्युलिन उत्पादके मांस कारखान्यात सह-उत्पादन म्हणून तयार व्हावयाची. इन्स्युलिनचा पुरवठा हा मांस कारखान्यातील पुरवठा व गरजेवर अवलंबून होता. पुन:संयोजी इ.कोलाय पेशीने व्यापारी तत्त्वावर तयार केलेल्या मानवीय इन्स्युलिनमुळे ते तयार करण्यात भविष्यात कमतरता राहण्याबाबत चिंता राहिलेली नाही. याशिवाय ज्यांना मधुमेह झाला आहे व ज्यांना बोव्हीन अथवा पोर्सीनचे वावडे आहे त्यांच्याकरिता मानवीय इन्स्युलिन अत्यंत उपयुक्त ठरेल. पुन:संयोजी डी.एन्.ए.चे तंत्र जीन थेरपीमध्ये महत्त्वाची भूमिका बजावते ज्यात ते प्रत्यक्षात सहभागी होऊन जीन साहित्यात फेरफार देखील करते. There are several products of genetic engineering now available in the market viz. interferon, human growth hormone and human insulin. In 1982, human insulin produced by recombinant bacteria was released for sale in the market. All of these proteins were previously purified from animal tissues. But human forms were available only in very minute quantities. Before 1982, all insulins which were utilized for diabetics were purified only from bovine of cattle and Porcine of pigs pancreas. These insulins were made available as by-products of meat industry. The insulin supply was, thus a function of supply and demand in the meat market. The commercial production of human insulin in recombinant E. Coli cells eliminated concerns regarding possible shortage of insulin in the future. In addition, this human insulin, was of particular importance to some diabetics who were allergic to bovine and/or porcine insulin. Recombinant DNA techniques play an essential role in gene therapy which involves the direct manipulation of genetic material.

What is life? One of our greatest difficulties in answering a question like this arises from language. We use words, and are inclined to think that a thing must correspond to every noun. Now some nouns stand for things; for example, bricks, water and coal - gas are things. Others are more doubtful. For example, a wave moves over the sea. We say that it is the same wave now as five minutes ago, but the particles of water in it are quite different. A tune has even less claim to be called a thing. It may be being played in several places at once, or nowhere. And some nouns like greenness or cleverness stand for qualities which no one, except a few philosophers, suppose to have any existence of their own. Where does life belong in a classification of this kind? When a man dies, we may say that he has lost his life, or that life has gone out of him. Is that just a metaphor? Is death the loss of something, or merely a change of state, as when a snowman melts, or a pattern is disarranged? The first people of whose ideas on this subject we know anything thought that life was the same as breath. But we know that breath consists of gas, which can be made into a solid or liquid, and also that many living things do not breathe. Life is certainly not a kind of matter. When a man or an animal dies he does not lose or gain in weight. Nor is there any measurable loss of energy. The heat gradually leaves the body, but is doing so throughout life. A dead body cools because no more heat is being generated inside it, not because anything measurable leaves it at the moment of death. Our ancestors thought that anything which moved itself was alive. And before the days of machinery that was quite a good definition. But a machine such as a motor-car or a steamship moves itself, and as soon as machines which moved themselves had been made, people asked, "Is man a machine?" the philosopher Descartes thought that both men and animals were machines, but that the human machine was partly controlled by the soul acting on a certain part of the brain, while animals had no souls. And some scientists think that life is just a very complicated mechanism.