Which of the following plamids do not possess information for self transfer to another cell? ?->(Show Answer!)

1. Which of the following plamids do not possess information for self transfer to another cell?

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MCQ-> The membrane-bound nucleus is the most prominent feature of the eukaryotic cell. Schleiden and Schwann, when setting forth the cell doctrine in the 1830s, considered that it had a central role in growth and development. Their belief has been fully supported even though they had only vague notions as to what that role might be, and how the role was to be expressed in some cellular action. The membraneless nuclear area of the prokaryotic cell, with its tangle of fine threads, is now known to play a similar role.Some cells, like the sieve tubes of vascular plants and the red blood cells of mammals, do not possess nuclei during the greater part of their existence, although they had nuclei when in a less differentiated state. Such cells can no longer divide and their life span is limited Other cells are regularly multinucleate. Some, like the cells of striated muscles or the latex vessels of higher plants, become so through cell fusion. Some, like the unicellular protozoan paramecium, are normally binucleate, one of the nuclei serving as a source of hereditary information for the next generation, the other governing the day-to-day metabolic activities of the cell. Still other organisms, such as some fungi, are multinucleate because cross walls, dividing the mycelium into specific cells, are absent or irregularly present. The uninucleate situation, however, is typical for the vast majority of cells, and it would appear that this is the most efficient and most economical manner of partitioning living substance into manageable units. This point of view is given credence not only by the prevalence of uninucleate cells, but because for each kind of cell there is a ratio maintained between the volume of the nucleus and that of the cytoplasm. If we think of the nucleus as the control centre of the cell, this would suggest that for a given kind of cell performing a given kind of work, one nucleus can ‘take care of’ a specific volume of cytoplasm and keep it in functioning order. In terms of material and energy, this must mean providing the kind of information needed to keep flow of materials and energy moving at the correct rate and in the proper channels. With the multitude of enzymes in the cell, materials and energy can of course be channelled in a multitude of ways; it is the function of some information molecules to make channels of use more preferred than others at any given time. How this regulatory control is exercised is not entirely clear.The nucleus is generally a rounded body. In plant cells, however, where the centre of the cell is often occupied by a large vacuole, the nucleus may be pushed against the cell wall, causing it to assume a lens shape. In some white blood cells, such as polymorphonucleated leukocytes, and in cells of the spinning gland of some insects and spiders, the nucleus is very much lobed The reason for this is not clear, but it may relate to the fact that for a given volume of nucleus, a lobate form provides a much greater surface area for nuclear-cytoplasmic exchanges, possibly affecting both the rate and the amount of metabolic reactions. The nucleus, whatever its shape, is segregated from the cytoplasm by a double membrane, the nuclear envelope, with the two membranes separated from each other by a perinuclear space of varying width. The envelope is absent only during the time of cell division, and then just for a brief period The outer membrane is often continuous with the membranes of the endoplasmic reticulum, a possible retention of an earlier relationship, since the envelope, at least in part, is formed at the end cell division by coalescing fragments of the endoplasmic reticulum. The cytoplasmic side of the nucleus is frequently coated with ribosomes, another fact that stresses the similarity and relation of the nuclear envelope to the endoplasmic reticulum. The inner membrane seems to posses a crystalline layer where it abuts the nucleoplasm, but its function remains to be determined.Everything that passes between the cytoplasm and the nucleus in the eukaryotic cell must transverse the nuclear envelope. This includes some fairly large molecules as well as bodies such as ribosomes, which measure about 25 mm in diameter. Some passageway is, therefore, obviously necessary since there is no indication of dissolution of the nuclear envelope in order to make such movement possible. The nuclear pores appear to be reasonable candidates for such passageways. In plant cells these are irregularly, rather sparsely distributed over the surface of the nucleus, but in the amphibian oocyte, for example, the pores are numerous, regularly arranged, and octagonal and are formed by the fusion of the outer and inner membrane.Which of the following kinds of cells never have a nuclei?
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MCQ->Which of the following plamids do not possess information for self transfer to another cell?....

MCQ-> Read the following passage carefully and answer the questions given below it. Certain words/phrases have been printed in ‘’bold’’ to help you locate them while answering some of the questions.As increasing dependence on information systems develops, the need for such system to be reliable and secure also becomes more essential. As growing numbers of ordinary citizens use computer networks for banking, shopping, etc., network security in potentially a ‘’massive’’ problem. Over the last few years, the need for computer and information security system has become increasingly evident, as web sites are being defaced with greater frequency, more and more denial-of-service attacks are being reported, credit card information is being stolen, there is increased sophistication of hacking tools that are openly available to the public on the Internet, and there is increasing damage being caused by viruses and worms to critical information system resources.At the organizational level, institutional mechanism have to be designed in order to review policies, practices, measures and procedures to review e-security regularly and assess whether these are appropriate to their environment. It would be helpful if organizations share information about threats and vulnerabilities, and implement procedures of rapid and effective cooperation to prevent, detect and respond to security incidents. As new threats and vulnerabilities are continuously discovered there is a strong need for co-operation among organizations and, if necessary, we could also consider cross-border information sharing. We need to understand threats and dangers that could be ‘’vulnerable’’ to and the steps that need to be taken to ‘’mitigate’’ these vulnerabilities. We need to understand access control systems and methodology, telecommunications and network security, and security management practise. We should be well versed in the area of application and systems development security, cryptography, operations security and physical security.The banking sector is ‘’poised’’ for more challenges in the near future. Customers of banks can now look forward to a large array of new offerings by banks, from an ‘’era’’ of mere competition, banks are now cooperating among themselves so that the synergistic benefits are shared among all the players. This would result in the information of shared payment networks (a few shared ATM networks have already been commissioned by banks), offering payment services beyond the existing time zones. The Reserve Bank is also facilitating new projects such as the Multi Application Smart Card Project which, when implemented, would facilitate transfer of funds using electronic means and in a safe and secure manner across the length and breadth of the country, with reduced dependence on paper currency. The opportunities of e-banking or e-power is general need to be harnessed so that banking is available to all customers in such a manner that they would feel most convenient, and if required, without having to visit a branch of a bank. All these will have to be accompanied with a high level of comfort, which again boils down to the issue of e-security.One of the biggest advantages accruing to banks in the future would be the benefits that arise from the introduction of Real Time Gross Settlement (RTGS). Funds management by treasuries of banks would be helped greatly by RTGS. With almost 70 banks having joined the RTGS system, more large value funds transfer are taking place through this system. The implementation of Core Banking solutions by the banks is closely related to RTGS too. Core Banking will make anywhere banking a reality for customers of each bank. while RTGS bridges the need for inter-bank funds movement. Thus, the days of depositing a cheque for collection and a long wait for its realization would soon be a thing of the past for those customers who would opt for electronic movement of funds, using the RTGS system, where the settlement would be on an almost ‘’instantaneous’’ basis. Core Banking is already in vogue in many private sector and foreign banks; while its implementation is at different stages amongst the public sector banks.IT would also facilitate better and more scientific decision-making within banks. Information system now provide decision-makers in banks with a great deal of information which, along with historical data and trend analysis, help in the building up of efficient Management Information Systems. This, in turn, would help in better Asset Liability Management (ALM) which, today’s world of hairline margins is a key requirement for the success of banks in their operational activities. Another benefit which e-banking could provide for relates to Customer Relationship Management (CRM). CRM helps in stratification of customers and evaluating customer needs on a holistic basis which could be paving the way for competitive edge for banks and complete customer care for customer of banks.The content of the passage ‘’mainly’’ emphasizes----
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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-> Read the passage given below and answer the questions that follow it:Elevation has always existed but has just moved out of the realm of philosophy and religion and been recognized as a distinct emotional state and a subject for psychological study. Psychology has long focused on what goes wrong, but in the past decade there has been an explosion of interest in “positive psychology”—what makes us feel good and why. University of Virginia moral psychologist Jonathan Haidt, who coined the term elevation, writes, “Powerful moments of elevation sometimes seem to push a mental ‘reset button,’ wiping out feelings of cynicism and replacing them with feelings of hope, love, and optimism, and a sense of moral inspiration.” Haidt quotes first-century Greek philosopher Longinus on great oratory: “The effect of elevated language upon an audience is not persuasion but transport.” Such feeling was once a part of our public discourse. After hearing Abraham Lincoln’s second inaugural address, former slave Frederick Douglass said it was a “sacred effort.” But uplifting rhetoric came to sound anachronistic, except as practiced by the occasional master like Martin Luther King Jr.It was while looking through the letters of Thomas Jefferson that Haidt first found a description of elevation. Jefferson wrote of the physical sensation that comes from witnessing goodness in others: It is to “dilate [the] breast and elevate [the] sentiments … and privately covenant to copy the fair example.” Haidt took this description as a mandate. Elevation can so often give us chills or a tingling feeling in the chest. This noticeable, physiological response is important. In fact, this physical reaction is what can tell us most surely that we have been moved. This reaction, and the prosocial inclinations it seems to inspire, has been linked with a specific hormone, oxytocin, emitted from Vagus nerve which works with oxytocin, the hormone of connection. The nerve’s activities can only be studied indirectly.Elevation is part of a family of self-transcending emotions. Some others are awe, that sense of the vastness of the universe and smallness of self that is often invoked by nature; another is admiration, that goose-bump-making thrill that comes from seeing exceptional skill in action. While there is very little lab work on the elevating emotions, there is quite a bit on its counterpart, disgust. It started as a survival strategy: Early humans needed to figure out when food was spoiled by contact with bacteria or parasites. From there disgust expanded to the social realm—people became repelled by the idea of contact with the defiled or by behaviors that seemed to belong to lower people. “Disgust is probably the most powerful emotion that separates your group from other groups.” Haidt says disgust is the bottom floor of a vertical continuum of emotion; hit the up button, and you arrive at elevation. Another response to something extraordinary in another person can be envy, with all its downsides. Envy is unlikely, however, when the extraordinary aspect of another person is a moral virtue (such as acting in a just way, bravery and self-sacrifice, and caring for others).Which of the options below is false according to the passage?
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