Many marine animals use _______________ dissolved in sea-water to make their shells. ?->(Show Answer!)

1. Many marine animals use _______________ dissolved in sea-water to make their shells.

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MCQ-> Read the passage carefully and answer the questions given at the end of each passage:We now come to the second part of our journey under the sea. The first ended with the moving scene in the coral cemetery which left a deep impression on my mind. I could no longer content myself with the theory which satisfied Conseil. That worthy fellow persisted in seeing in the Commander of the Nautilus one of those unknown servants who returns mankind contempt for indifference. For him, he was a misunderstood genius who, tired of earth’s deceptions, had taken refuge in this inaccessible medium, where he might follow his instincts freely. To my mind, this explains but one side of Captain Nemo’s character. Indeed, the mystery of that last night during which we had been chained in prison, the sleep, and the precaution so violently taken by the Captain of snatching from my eyes the glass I had raised to sweep the horizon, the mortal wound of the man, due to an unaccountable shock of the Nautilus, all put me on a new track. No; Captain Nemo was not satisfied with shunning man. His formidable apparatus not only suited his instinct of freedom, but perhaps also the design of some terrible retaliation. That day, at noon, the second officer came to take the altitude of the sun. I mounted the platform, and watched the operation. As he was taking observations with the sextant, one of the sailors of the Nautilus (the strong man who had accompanied us on our first submarine excursion to the Island of Crespo) came to clean the glasses of the lantern. I examined the fittings of the apparatus, the strength of which was increased a hundredfold by lenticular rings, placed similar to those in a lighthouse, and which projected their brilliance in a horizontal plane. The electric lamp was combined in such a way as to give its most powerful light. Indeed, it was produced in vacuo, which insured both its steadiness and its intensity. This vacuum economized the graphite points between which the luminous arc was developed - an important point of economy for Captain Nemo, who could not easily have replaced them; and under these conditions their waste was imperceptible. When the Nautilus was ready to continue its submarine journey, I went down to the saloon. The panel was closed, and the course marked direct west. We were furrowing the waters of the Indian Ocean, a vast liquid plain, with a surface of 1,200,000,000 of acres, and whose waters are so clear and transparent that any one leaning over them would turn giddy. The Nautilus usually floated between fifty and a hundred fathoms deep. We went on so for some days. To anyone but myself, who had a great love for the sea, the hours would have seemed long and monotonous; but the daily walks on the platform, when I steeped myself in the reviving air of the ocean, the sight of the rich waters through the windows of the saloon, the books in the library, the compiling of my memoirs, took up all my time, and left me not a moment of ennui or weariness. From the 21 st to the 23 rd of January the Nautilus went at the rate of two hundred and fifty leagues in twenty- four hours, being five hundred and forty miles, or twenty-two miles an hour. If we recognized so many different varieties of fish, it was because, attracted by the electric light, they tried to follow us; the greater part, however, were soon distanced by our speed, though some kept their place in the waters of the Nautilus for a time. The morning of the 24 th , we observed Keeling Island, a coral formation, planted with magnificent cocos, and which had been visited by Mr. Darwin and Captain Fitzroy. The Nautilus skirted the shores of this desert island for a little distance. Soon Keeling Island disappeared from the horizon, and our course was directed to the north- west in the direction of the Indian Peninsula. From Keeling Island our course was slower and more variable, often taking us into great depths. Several times they made use of the inclined planes, which certain internal levers placed obliquely to the waterline. I observed that in the upper regions the water was always colder in the high levels than at the surface of the sea. On the 25th of January the ocean was entirely deserted; the Nautilus passed the day on the surface, beating the waves with its powerful screw and making them rebound to a great height. Three parts of this day I spent on the platform. I watched the sea. Nothing on the horizon till about four o’clock then there was a steamer running west on our counter. Her masts were visible for an instant, but she could not see the Nautilus, being too low in the water. I fancied this steamboat belonged to the P.O. Company, which runs from Ceylon to Sydney, touching at King George’s Point and Melbourne. At five o’clock in the evening, before that fleeting twilight which binds night to day in tropical zones, Conseil and I were astonished by a curious spectacle. It was a shoal of Argonauts travelling along on the surface of the ocean. We could count several hundreds. These graceful molluscs moved backwards by means of their locomotive tube, through which they propelled the water already drawn in. Of their eight tentacles, six were elongated, and stretched out floating on the water, whilst the other two, rolled up flat, were spread to the wing like a light sail. I saw their spiral-shaped and fluted shells, which Cuvier justly compares to an elegant skiff. For nearly an hour the Nautilus floated in the midst of this shoal of molluscs. The next day, 26 th of January, we cut the equator at the eighty-second meridian and entered the northern hemisphere. During the day a formidable troop of sharks accompanied us. They were “cestracio philippi” sharks, with brown backs and whitish bellies, armed with eleven rows of teeth, their throat being marked with a large black spot surrounded with white like an eye. There were also some Isabella sharks, with rounded snouts marked with dark spots. These powerful creatures often hurled themselves at the windows of the saloon with such violence as to make us feel very insecure. But the Nautilus, accelerating her speed, easily left the most rapid of them behind.About seven o’clock in the evening, the Nautilus, half- immersed, was sailing in a sea of milk. At first sight the ocean seemed lactified. Was it the effect of the lunar rays? No; for the moon, scarcely two days old, was still lying hidden under the horizon in the rays of the sun. The whole sky, though lit by the sidereal rays, seemed black by contrast with the whiteness of the waters. Conseil could not believe his eyes, and questioned me as to the cause of this strange phenomenon. Happily I was able to answer him. “It is called a milk sea,” I explained. “A large extent of white waves is often to be seen on the coasts of Amboyna, and in these parts of the sea.” “But, sir,” said Conseil, “can you tell me what causes such an effect? For I suppose the water is not really turned into milk.” “No, my boy; and the whiteness which surprises you is caused only by the presence of myriads of luminous little worm, gelatinous and without colour, of the thickness of a hair, and whose length is not more than seven-thousandths of an inch. These insects adhere to one another sometimes for several leagues.” “Several leagues!” exclaimed Conseil. “Yes, my boy; and you need not try to compute the number of these infusoria. You will not be able, for, if I am not mistaken, ships have floated on these milk seas for more than forty miles.” Towards midnight the sea suddenly resumed its usual colour; but behind us, even to the limits of the horizon, the sky reflected the whitened waves, and for a long time seemed impregnated with the vague glimmerings of an aurora borealisFind the TRUE Sentence:
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MCQ->Many marine animals use _______________ dissolved in sea-water to make their shells.....

MCQ-> Read the following passage and answer the questions. Passage: A new paper published by Rochman and her colleagues in February, in the journal Ecology, sifts through past research on marine debris to assess the true extent of the environmental threat. Plenty of studies have sounded alarm bells about the state of marine debris: Rochman and her colleagues set out to determine how many of those perceived risks are real Often. Rochman says, scientists will wrap up a paper by speculating about the broader impacts of what they've found. Maybe their study has shown that certain seabirds eat plastic bags, for example, and the paper goes on to warn that whole bird populations are at risk of dying out. "But the truth was that nobody had yet tested those perceived threats." Rochman says. "There wasn't a lot of information." Rochman and her colleagues examined more than a hundred papers on the impacts of marine debris that were published through 2013. Within each paper. they asked what threats scientists had studied-366 perceived threats in all and what they'd actually found. In 83 percent of cases, the perceived dangers of ocean trash were proven true. In most of the remaining cases. the working group found the studies too shoddy to draw conclusions from—they lacked a control group, for example. or used faulty statistics. Strikingly. Rochman says, only one well-designed study failed to find the effect it was looking for, an investigation of mussels ingesting microscopic plastic bits. The plastic moved from the mussels' stomachs to their bloodstreams. scientists found. and stayed there for weeks—but didn't seem to stress out the shellfish. A lot of ocean debris is "microplastic," or pieces smaller than five millimetres. These may be the beads from a facial scrub. fibres shed by synthetic clothing in the wash. or eroded remnants of larger debris. Compared to the number of studies investigating large-scale debris. Roclunan's group found little research on the effects of these tiny bits. There are also, she adds, a lot of open questions about the ways that ocean debris can lead to sea-creature death. Many studies have looked at how plastic affects an individual animal or that animal's tissues or cells, rather than whole populations. And in the lab, scientists often use higher concentrations of plastic than what's really in the ocean. None of that tells us how many birds or fish or sea turtles could die form plastic pollution or how deaths in one species could affect that animal's predators, or the rest of the ecosystem. "We need to be asking more ecologically relevant questions." Rothman says. Usually, scientists don't know how disasters like oil spills or nuclear meltdowns will affect the environment until after they've happened. she says. "We don't ask the right questions early enough." But if ecologists can understand how the slow-moving disaster of ocean garbage is affecting ecosystems. they might be able to prevent things from getting worse.Which ONE of the following conclusions based on the examination of the hundred-odd papers on marine debris and its ecological impact by Rachman and her colleagues is NOT CORRECT?
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MCQ-> I want to stress this personal helplessness we are all stricken with in the face of a system that has passed beyond our knowledge and control. To bring it nearer home, I propose that we switch off from the big things like empires and their wars to more familiar little things. Take pins for example! I do not know why it is that I so seldom use a pin when my wife cannot get on without boxes of them at hand; but it is so; and I will therefore take pins as being for some reason specially important to women.There was a time when pinmakers would buy the material; shape it; make the head and the point; ornament it; and take it to the market, and sell it and the making required skill in several operations. They not only knew how the thing was done from beginning to end, but could do it all by themselves. But they could not afford to sell you a paper of pins for the farthing. Pins cost so much that a woman's dress allowance was calling pin money.By the end of the 18th century Adam Smith boasted that it took 18 men to make a pin, each man doing a little bit of the job and passing the pin on to the next, and none of them being able to make a whole pin or to buy the materials or to sell it when it was made. The most you could say for them was that at least they had some idea of how it was made, though they could not make it. Now as this meant that they were clearly less capable and knowledgeable men than the old pin-makers, you may ask why Adam Smith boasted of it as a triumph of civilisation when its effect had so clearly a degrading effect. The reason was that by setting each man to do just one little bit of the work and nothing but that, over and over again, he became very quick at it. The men, it is said, could turn out nearly 5000 pins a day each; and thus pins became plentiful and cheap. The country was supposed to be richer because it had more pins, though it had turned capable men into mere machines doing their work without intelligence and being fed by the spare food of the capitalist just as an engine is fed with coals and oil. That was why the poet Goldsmith, who was a farsighted economist as well as a poet, complained that 'wealth accumulates, and men decay'.Nowadays Adam Smith's 18 men are as extinct as the diplodocus. The 18 flesh-and-blood men have been replaced by machines of steel which spout out pins by the hundred million. Even sticking them into pink papers is done by machinery. The result is that with the exception of a few people who design the machines, nobody knows how to make a pin or how a pin is made: that is to say, the modern worker in pin manufacture need not be one-tenth so intelligent, skilful and accomplished as the old pinmaker; and the only compensation we have for this deterioration is that pins are so cheap that a single pin has no expressible value at all. Even with a big profit stuck on to the cost-price you can buy dozens for a farthing; and pins are so recklessly thrown away and wasted that verses have to be written to persuade children (without success) that it is a sin to steal, if even it’s a pin.Many serious thinkers, like John Ruskin and William Morris, have been greatly troubled by this, just as Goldsmith was, and have asked whether we really believe that it is an advance in wealth to lose our skill and degrade our workers for the sake of being able to waste pins by the ton. We shall see later on, when we come to consider the Distribution of Leisure, that the cure for this is not to go back to the old free for higher work than pin-making or the like. But in the meantime the fact remains that the workers are now not able to make anything themselves even in little bits. They are ignorant and helpless, and cannot lift their finger to begin their day's work until it has all been arranged for them by their employer's who themselves do not understand the machines they buy, and simply pay other people to set them going by carrying out the machine maker's directions.The same is true for clothes. Earlier the whole work of making clothes, from the shearing of the sheep to the turning out of the finished and washed garment ready to put on, had to be done in the country by the men and women of the household, especially the women; so that to this day an unmarried woman is called a spinster. Nowadays nothing is left of all this but the sheep shearing; and even that, like the milking of cows, is being done by machinery, as the sewing is. Give a woman a sheep today and ask her to produce a woollen dress for you; and not only will she be quite unable to do it, but you are likely to find that she is not even aware of any connection between sheep and clothes. When she gets her clothes, which she does by buying them at the shop, she knows that there is a difference between wool and cotton and silk, between flannel and merino, perhaps even between stockinet and other wefts; but as to how they are made, or what they are made of, or how they came to be in the shop ready for her to buy, she knows hardly anything. And the shop assistant from whom she buys is no wiser. The people engaged in the making of them know even less; for many of them are too poor to have much choice of materials when they buy their own clothes.Thus the capitalist system has produced an almost universal ignorance of how things are made and done, whilst at the same time it has caused them to be made and done on a gigantic scale. We have to buy books and encyclopaedias to find out what it is we are doing all day; and as the books are written by people who are not doing it, and who get their information from other books, what they tell us is twenty to fifty years out of date knowledge and almost impractical today. And of course most of us are too tired of our work when we come home to want to read about it; what we need is cinema to take our minds off it and feel our imagination.It is a funny place, this word of capitalism, with its astonishing spread of education and enlightenment. There stand the thousands of property owners and the millions of wage workers, none of them able to make anything, none of them knowing what to do until somebody tells them, none of them having the least notion of how it is made that they find people paying them money, and things in the shops to buy with it. And when they travel they are surprised to find that savages and Esquimaux and villagers who have to make everything for themselves are more intelligent and resourceful! The wonder would be if they were anything else. We should die of idiocy through disuse of our mental faculties if we did not fill our heads with romantic nonsense out of illustrated newspapers and novels and plays and films. Such stuff keeps us alive, but it falsifies everything for us so absurdly that it leaves us more or less dangerous lunatics in the real world.Excuse my going on like this; but as I am a writer of books and plays myself, I know the folly and peril of it better than you do. And when I see that this moment of our utmost ignorance and helplessness, delusion and folly, has been stumbled on by the blind forces of capitalism as the moment for giving votes to everybody, so that the few wise women are hopelessly overruled by the thousands whose political minds, as far as they can be said to have any political minds at all, have been formed in the cinema, I realise that I had better stop writing plays for a while to discuss political and social realities in this book with those who are intelligent enough to listen to me.A suitable title to the passage would be
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MCQ-> Read the following passage and answer the questions. Passage: An old man with steel rimmed spectacles and very dusty clothes sat by the side of the road. There was a pontoon bridge across the river and carts, trucks, and men, women and children were crossing it. The mule-drawn carts staggered up the steep bank from the bridge with soldiers helping to push against the spokes of the wheels. The trucks ground up and away heading out of it all and the peasants plodded along in the ankle deep dust. But the old man sat there without moving. He was too tired to go any farther. It was my business to cross the bridge, explore the bridgehead beyond and find out to what point the enemy had advanced. I did this and returned over the bridge. There were not so many carts now and very few people on foot, but the old man was still there. "Where do you come from?" I asked him. "From San Carlos," he said, and smiled. That was his native town and so it gave him pleasure to mention it and he smiled. "I was taking care of animals." he explained. "Oh," I said, not quite understanding. "Yes," he said, "I stayed. you see, taking care of animals. I was the last one to leave the town of San Carlos." He did not look like a shepherd nor a herdsman and I looked at his black dusty clothes and his gray dusty face and his steel rimmed spectacles and said. "What animals were they?" "Various animals." he said. and shook his head. "I had to leave them." I was watching the bridge and the African looking country of the Ebro Delta wondering how long now it would be before we would see the enemy.. "What animals were they?" I asked. "There were three animals altogether," he explained. "There were two goats and a cat and then there were four pairs of pigeons." "And you had to leave them?" I asked. "Yes. Because of the artillery. The captain told me to go because of the artillery." "And you have no family?" I asked, watching the far end of the bridge where a few last carts were hurrying down the slope of the bank. "No," he said, "only the animals I stated. The cat, of course, will be all right. A cat can look out for itself. but I cannot think what will become of the others." "What politics have you?" I asked. "I am without politics," he said. "I am seventy-six years old. I have come twelve kilometers now and I think now I can go no further." "This is not a good place to stop," I said. "If you can make it, there are trucks up the road where it forks for Tortosa." "I will wait a while," he said, "and then I will go. Where do the trucks go?" "Towards Barcelona," I told him.Where was the old man coming from?
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