Which one of the following is the most primitive ancestor of man ? ?->(Show Answer!)

1. Which one of the following is the most primitive ancestor of man ?

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QA->Which is most primitive ancestor of man?....

QA->Which is most primitive ancestor of man ?....

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QA->From the evolutionary point of view; which is the most primitive animal?....

QA->From the evolutionary point of view, which is the most primitive animal?....

MCQ-> Cells are the ultimate multi-taskers: they can switch on genes and carry out their orders, talk to each other, divide in two, and much more, all at the same time. But they couldn’t do any of these tricks without a power source to generate movement. The inside of a cell bustles with more traffic than Delhi roads, and, like all vehicles, the cell’s moving parts need engines. Physicists and biologists have looked ‘under the hood’ of the cell and laid out the nuts and bolts of molecular engines.The ability of such engines to convert chemical energy into motion is the envy nanotechnology researchers looking for ways to power molecule-sized devices. Medical researchers also want to understand how these engines work. Because these molecules are essential for cell division, scientists hope to shut down the rampant growth of cancer cells by deactivating certain motors. Improving motor-driven transport in nerve cells may also be helpful for treating diseases such as Alzheimer’s, Parkinson’s or ALS, also known as Lou Gehrig’s disease.We wouldn’t make it far in life without motor proteins. Our muscles wouldn’t contract. We couldn’t grow, because the growth process requires cells to duplicate their machinery and pull the copies apart. And our genes would be silent without the services of messenger RNA, which carries genetic instructions over to the cell’s protein-making factories. The movements that make these cellular activities possible occur along a complex network of threadlike fibers, or polymers, along which bundles of molecules travel like trams. The engines that power the cell’s freight are three families of proteins, called myosin, kinesin and dynein. For fuel, these proteins burn molecules of ATP, which cells make when they break down the carbohydrates and fats from the foods we eat. The energy from burning ATP causes changes in the proteins’ shape that allow them to heave themselves along the polymer track. The results are impressive: In one second, these molecules can travel between 50 and 100 times their own diameter. If a car with a five-foot-wide engine were as efficient, it would travel 170 to 340 kilometres per hour.Ronald Vale, a researcher at the Howard Hughes Medical Institute and the University of California at San Francisco, and Ronald Milligan of the Scripps Research Institute have realized a long-awaited goal by reconstructing the process by which myosin and kinesin move, almost down to the atom. The dynein motor, on the other hand, is still poorly understood. Myosin molecules, best known for their role in muscle contraction, form chains that lie between filaments of another protein called actin. Each myosin molecule has a tiny head that pokes out from the chain like oars from a canoe. Just as rowers propel their boat by stroking their oars through the water, the myosin molecules stick their heads into the actin and hoist themselves forward along the filament. While myosin moves along in short strokes, its cousin kinesin walks steadily along a different type of filament called a microtubule. Instead of using a projecting head as a lever, kinesin walks on two ‘legs’. Based on these differences, researchers used to think that myosin and kinesin were virtually unrelated. But newly discovered similarities in the motors’ ATP-processing machinery now suggest that they share a common ancestor — molecule. At this point, scientists can only speculate as to what type of primitive cell-like structure this ancestor occupied as it learned to burn ATP and use the energy to change shape. “We’ll never really know, because we can’t dig up the remains of ancient proteins, but that was probably a big evolutionary leap,” says Vale.On a slightly larger scale, loner cells like sperm or infectious bacteria are prime movers that resolutely push their way through to other cells. As L. Mahadevan and Paul Matsudaira of the Massachusetts Institute of Technology explain, the engines in this case are springs or ratchets that are clusters of molecules, rather than single proteins like myosin and kinesin. Researchers don’t yet fully understand these engines’ fueling process or the details of how they move, but the result is a force to be reckoned with. For example, one such engine is a spring-like stalk connecting a single-celled organism called a vorticellid to the leaf fragment it calls home. When exposed to calcium, the spring contracts, yanking the vorticellid down at speeds approaching three inches (eight centimetres) per second.Springs like this are coiled bundles of filaments that expand or contract in response to chemical cues. A wave of positively charged calcium ions, for example, neutralizes the negative charges that keep the filaments extended. Some sperm use spring-like engines made of actin filaments to shoot out a barb that penetrates the layers that surround an egg. And certain viruses use a similar apparatus to shoot their DNA into the host’s cell. Ratchets are also useful for moving whole cells, including some other sperm and pathogens. These engines are filaments that simply grow at one end, attracting chemical building blocks from nearby. Because the other end is anchored in place, the growing end pushes against any barrier that gets in its way.Both springs and ratchets are made up of small units that each move just slightly, but collectively produce a powerful movement. Ultimately, Mahadevan and Matsudaira hope to better understand just how these particles create an effect that seems to be so much more than the sum of its parts. Might such an understanding provide inspiration for ways to power artificial nano-sized devices in the future? “The short answer is absolutely,” says Mahadevan. “Biology has had a lot more time to evolve enormous richness in design for different organisms. Hopefully, studying these structures will not only improve our understanding of the biological world, it will also enable us to copy them, take apart their components and recreate them for other purpose.”According to the author, research on the power source of movement in cells can contribute to
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MCQ-> Fifty feet away three male lions lay by the road. They didn’t appear to have a hair on their heads. Noting the color of their noses (leonine noses darken as they age, from pink to black), Craig estimated that they were six years old — young adults. “This is wonderful!” he said, after staring at them for several moments. “This is what we came to see. They really are maneless.” Craig, a professor at the University of Minnesota, is arguably the leading expert on the majestic Serengeti lion, whose head is mantled in long, thick hair. He and Peyton West, a doctoral student who has been working with him in Tanzania, had never seen the Tsavo lions that live some 200 miles east of the Serengeti. The scientists had partly suspected that the maneless males were adolescents mistaken for adults by amateur observers. Now they knew better.The Tsavo research expedition was mostly Peyton’s show. She had spent several years in Tanzania, compiling the data she needed to answer a question that ought to have been answered long ago: Why do lions have manes? It’s the only cat, wild or domestic, that displays such ornamentation. In Tsavo she was attacking the riddle from the opposite angle. Why do its lions not have manes? (Some “maneless” lions in Tsavo East do have partial manes, but they rarely attain the regal glory of the Serengeti lions.) Does environmental adaptation account for the trait? Are the lions of Tsavo, as some people believe, a distinct subspecies of their Serengeti cousins?The Serengeti lions have been under continuous observation for more than 35 years, beginning with George Schaller’s pioneering work in the 1960s. But the lions in Tsavo, Kenya’s oldest and largest protected ecosystem, have hardly been studied. Consequently, legends have grown up around them. Not only do they look different, according to the myths, they behave differently, displaying greater cunning and aggressiveness. “Remember too,” Kenya: The Rough Guide warns, “Tsavo’s lions have a reputation of ferocity.” Their fearsome image became well-known in 1898, when two males stalled construction of what is now Kenya Railways by allegedly killing and eating 135 Indian and African laborers. A British Army officer in charge of building a railroad bridge over the Tsavo River, Lt. Col. J. H. Patterson, spent nine months pursuing the pair before he brought them to bay and killed them. Stuffed and mounted, they now glare at visitors to the Field Museum in Chicago. Patterson’s account of the leonine reign of terror, The Man-Eaters of Tsavo, was an international best seller when published in 1907. Still in print, the book has made Tsavo’s lions notorious. That annoys some scientists. “People don’t want to give up on mythology,” Dennis King told me one day. The zoologist has been working in Tsavo off and on for four years. “I am so sick of this maneater business. Patterson made a helluva lot of money off that story, but Tsavo’s lions are no more likely to turn man-eater than lions from elsewhere.”But tales of their savagery and wiliness don’t all come from sensationalist authors looking to make a buck. Tsavo lions are generally larger than lions elsewhere, enabling them to take down the predominant prey animal in Tsavo, the Cape buffalo, one of the strongest, most aggressive animals of Earth. The buffalo don’t give up easily: They often kill or severely injure an attacking lion, and a wounded lion might be more likely to turn to cattle and humans for food.And other prey is less abundant in Tsavo than in other traditional lion haunts. A hungry lion is more likely to attack humans. Safari guides and Kenya Wildlife Service rangers tell of lions attacking Land Rovers, raiding camps, stalking tourists. Tsavo is a tough neighborhood, they say, and it breeds tougher lions.But are they really tougher? And if so, is there any connection between their manelessness and their ferocity? An intriguing hypothesis was advanced two years ago by Gnoske and Peterhans: Tsavo lions may be similar to the unmaned cave lions of the Pleistocene. The Serengeti variety is among the most evolved of the species — the latest model, so to speak — while certain morphological differences in Tsavo lions (bigger bodies, smaller skulls, and maybe even lack of a mane) suggest that they are closer to the primitive ancestor of all lions. Craig and Peyton had serious doubts about this idea, but admitted that Tsavo lions pose a mystery to science.The book Man-Eaters of Tsavo annoys some scientists because
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MCQ-> Every age has its pet contradictions. A few decades back, we used to accept Marx and Freud together, and then wonder, like the chameleon on the turkey carpet, why life was so confusing. Today there is similar trouble over the question whether there is, or is not, something called Human Nature. On the one hand, there has been an explosion of animal behavior studies, and comparisons between animals and men have become immensely popular. People use evidence from animals to decide whether man is naturally aggressive, or naturally territorial; even whether he has an aggressive or territorial instinct. Moreover, we are still much influenced by Freudian psychology, which depends on the notion of instinct. On the other hand, many still hold what may be called the Blank Paper view, that man is a creature entirely without instincts. So do Existentialist philosophers. If man has no instincts, all comparison with animals must be irrelevant. (Both these simple party lines have been somewhat eroded over time, but both are still extremely influential.)According to the Blank Paper view, man is entirely the product of his culture. He starts off infinitely plastic, and is formed completely by the society in which he grows up. There is then no end to the possible variations among cultures; what we take to be human instincts are just the deep-dug prejudices of our own society. Forming families, fearing the dark, and jumping at the sight of a spider are just results of our conditioning. Existentialism at first appears a very different standpoint, because the Existentialist asserts man’s freedom and will not let him call himself a product of anything. But Existentialism too denies that man has a nature; if he had, his freedom would not be complete. Thus Sartre insisted that “there is no human nature …. Man first of all exists, encounters himself, surges up in the world, and defines himself afterwards. If man as the Existentialist sees him is not definable, it is because to begin with he is nothing. He will not be anything until later, and then he will be what he makes himself.” For Existentialism there is only the human condition, which is what happens to man and not what he is born like. If we are afraid of the dark, it is because we choose to be cowards; if we care more for our own children than for other people’s, it is because we choose to be partial. We must never talk about human nature or human instincts. This implicit moral notion is still very influential, not at all confined to those who use the metaphysic of essence and existence. So I shall sometimes speak of it, not as Existentialist, but as Libertarian ― meaning that those holding it do not just (like all of us) think liberty important, but think it supremely important and believe that our having a nature would infringe it.Philosophers have not yet made much use of informed comparison with other species as a help in the understanding of man. One reason they have not is undoubtedly the fear of fatalism. Another is the appalling way terms such as instinct and human nature have been misused in the past. A third is the absurdity of some ethological propaganda.A business school led by an existentialist director, wanted to decide on admission policy for its executive MBA program, which requires candidates to possess minimum five years of managerial experience.With respect to the selection process, which of the following statements will be closest to the director’s belief:
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MCQ-> Analyze the following passage and provide appropriate answers for the questions that follow. The ways by which you may get money almost exception lead downwards. To have done anything by which you earned money merely is to have been trulyidle or worse. If the laborer gets no more than the wages which his employer pays him, he is cheated, he cheats himself. If you would get money as a writer or lecturer, you must be popular, which is to go down perpendicularly. Those services which the community will most readily pay for, it is most disagreeable to render. You are paid for being something less than a man. The State does not commonly reward a genius any more wisely. Even the poet laureate would rather not have to celebrate the accidents of royalty. He must be bribed with a pipe of wine; and perhaps another poet is called away from his muse to gauge that very pipe. The aim of the laborer should be, not to get his living, to get “a good job.” but to perform well a certain work; and even in a pecuniary sense, it would be economy for a town to pay its laborers so well that they would not feel that they were working for low ends, for a livelihood merely, but for scientific, or even moral ends. Do not hire a man who does your work for money, but him who does it for love of it. The community has no bribe that will tempt a wise man. You may raise money enough to tunnel a mountain, but you cannot raise money enough to hire a man who is minding his own business. An efficient and valuable man does what he can, whether the community pays him for it or not. The inefficient offer their inefficiency to the highest bidder, and are forever expecting to be put into office. One would suppose that they were rarely disappointed. God gave the righteous man a certificate entitling him to food and raiment, but the unrighteous man found a facsimile of the same in God’s coffers, and appropriated it, and obtained food and raiment like the former. It is one of the most extensive systems of counterfeiting that the world has seen. I did not know that mankind was suffering for want of gold. I have seen a little of it. I know that it is very malleable, but not so malleable as wit. A grain of gold will gild a great surface, but not so much as a grain of wisdom.Which of the following would the author disagree most with?
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MCQ-> Read the following passage carefully and answer the questions given below it. Certain words/phrases have been given in bold to help you locate them while answering some of the questions: In every religion, culture and civilization feeding the poor and hungry is considered one of the most noble deeds. However such large scale feeding will require huge investment both in resources and time. A better alternative is to create conditions by which proper wholesome food is available to all the rural poor at affordable price. Getting this done will be the biggest charity.Our work with the rural poor in villages of Western Maharashtra has shown that most of these people are landless laborers. After working the whole day in the fields in scorching sun they come home in the evening and have to cook for the whole family. The cooking is done on the most primitive chulha (wood stove) which results in tremendous indoor air pollution. Many of them also have no electricity so they use primitive and polluting kerosene lamps. World Health Organization (WHO) data has shown that about 300,000 deaths/ year in India can be directly attributed to indoor air pollution in such -nuts. At the same time this pollution results in many respiratory ailments and these people spend close Rs. 200-400 per month on medical bills. Besides the pollution, rural poor also eat very poor diet. They eat whatever is available daily at Public Distribution System (PDS) shops and most of the times these shops are out of rations. Thus they cook whatever is available. The hard work together with poor eating takes a heavy toll on their health. Besides this malnutrition also affects the physical and mental health of their children and may lead to creation of a whole generation of mentally challenged citizens. So I feel that the best way to provide adequate food for rural poor is by setting up rural restaurants on large scale. These restaurants will be similar to regular ones but for people below poverty line (BPL) they will provide meals at subsidized rates. These citizens will pay only Rs. 10 per meal and the rest, which is expected to be quite small, will come as a part of Government subsidy. With existing open market prices of vegetables and groceries average cost of simple meal for a family of four comes to Rs. 50 per meal or Rs. 12.50 per person per meal. If the PDS prices are taken for the groceries then the average cost will be Rs. 7.50 per person per meal. This makes the subsidy approximately Rs. 2.50 per person per meal only and hence quite small. The buying of meals could be by the use of UID (Aadhar) card by rural poor. The total cost should be Rs. 30 per day for three vegetarian meals of breakfast, lunch and dinner. The rural poor will get better nutrition and tasty food by eating in these restaurants. Besides the time saved can be used for resting and other gainful activities like teaching children. Since the food will not be cooked in huts, this strategy will result in less pollution in rural households. This will be beneficial for their health. Besides, women's chores will be reduced drastically. Another advantage of eating in these restaurants will be increased social interaction of rural poor since this could also become a meeting place. Eating in restaurants will also require fewer utensils in house and hence less expenditure. For other things like hot water for bath, making tea, boiling milk and cooking on holidays some utensils and fuel will be required. Our Institute NARI has developed an extremely efficient and environment-friendly stove which provides simultaneously both light and heat for cooking and hence may provide the necessary functions. Providing reasonably priced wholesome food is the basic aim and program of Government of India (GOI). This is the basis of their much touted food security program.However in 65years they have not been able to do so. Thus I feel a public private partnership can help in this. To help the restaurant owners the GOI or state Governments should provide them with soft loans and other line of credit for setting up such facilities. Corporate world can take this up as a part of their corporate social responsibility activity. Their participation will help ensure good quality restaurants and services. Besides the charitable work, this will also make good business sense. McDonald's-type restaurant systems for rural areas can be a good model to be set up for quality control both in terms of hygiene and in terms of quality of food material. However focus will be on availability of wholesome simple vegetarian food in these restaurants.More clientele (volumes) will make these restaurants economical. Existing models of dhabas, udipi type restaurants etc. can be used in this scheme. These restaurants may also be able to provide midday meals in rural schools. At present the midday meal program is faltering due to various reasons. Food coupons in western countries provide cheap food for poor. However quite a number of fast food restaurants in US do not accept them. Besides these coupons are most of the times used for non-food items, it will be mandatory for rural restaurants to accept payment via UID cards for BPL citizens. Existing soup kitchens, lagers and temple food are based on charity. For large scale rural use it should be based on good social enterprise business model. Cooking food in these restaurants will also result in much more efficient use of energy since energy/ kg of food cooked in households is greater than that in restaurants. The main thing however will be to reduce drastically the food wastage In these restaurants. Rural restaurants can also be forced to use clean fuels like LPG or locally produced biomass-based liquid fuels. This strategy is very difficult to enforce for individual households. Large scale employment generation in rural areas may result because of this activity. With an average norm of 30 people employed/ 100-chair restaurant, this program has the potential of generating about 20 million jobs permanently in rural areas. Besides the infrastructure development in setting up restaurants and establishing the food chain etc will help the local farmers and will create huge wealth generation in these areas. In the long run this strategy may provide better food security for rural poor than the existing one which is based on cheap food availability in PDS - a system which is prone to corruption and leakage.In accordance with the view expressed by the writer of this article, what is the biggest charity ?
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