Which type of restriction enzymes do not usually require ATP? ?->(Show Answer!)

1. Which type of restriction enzymes do not usually require ATP?

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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->Which type of restriction enzymes do not usually require ATP?....

MCQ-> Answer questions on the basis of information given in the following case. Bright Engineering College (BEC) has listed 20 elective courses for the next term and students have to choose any 7 of them. Simran, a student of BEC, notices that there are three categories of electives: Job - oriented (J), Quantitative - oriented (Q) and Grade - oriented (G). Among these 20 electives, some electives are both Job and Grade - oriented but are not Quantitative - oriented (JG type). QJ type electives are both job and Quantitative - oriented but are not Grade - oriented and QG type electives are both Quantitative and Grade - oriented but are not Job - oriented. Simran also notes that the total number of QJ type electives is 2 less than QG type electives. Similarly, the total number of QG type electives is 2 less than JG type and there is only 1 common elective (JQG) across three categories. Furthermore, the number of only Quantitative - oriented electives is same as only Job - oriented electives, but less than the number of only Grade - oriented electives. Each elective has at least one registration and there is at least one elective in each category, or combinations of categories.On her way back Simran met her friend Raj and shared the above information. Raj is preparing for XAT and is only interested in Grade - oriented (G) electives. He wanted to know the number of G - type electives being offered. Simran replied, “You have all the information. Calculate the number of G - type electives yourself. It would help your XAT preparation”. Raj calculates correctly and says that there can be _______ possible answers. Which of the following options would b est fit the blank above?
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MCQ->The ATP/ AMP ratio has a major effect upon the rate of ATP production by glycolysis. ATP and AMP bind to allosteric sites on :....

MCQ-> Read the following passage carefully and answer the questions given at the end.Passage 4Public sector banks (PSBs) are pulling back on credit disbursement to lower rated companies, as they keep a closer watch on using their own scarce capital and the banking regulator heightens its scrutiny on loans being sanctioned. Bankers say the Reserve Bank of India has started strictly monitoring how banks are utilizing their capital. Any big-ticket loan to lower rated companies is being questioned. Almost all large public sector banks that reported their first quarter results so far have showed a contraction in credit disbursal on a year-to-date basis, as most banks have shifted to a strategy of lending largely to government-owned "Navratna" companies and highly rated private sector companies. On a sequential basis too, banks have grown their loan book at an anaemic rate.To be sure, in the first quarter, loan demand is not quite robust. However, in the first quarter last year, banks had healthier loan growth on a sequential basis than this year. The country's largest lender State Bank of India grew its loan book at only 1.21% quarter-on-quarter. Meanwhile, Bank of Baroda and Punjab National Bank shrank their loan book by 1.97% and 0.66% respectively in the first quarter on a sequential basis.Last year, State Bank of India had seen sequential loan growth of 3.37%, while Bank of Baroda had seen a smaller contraction of 0.22%. Punjab National Bank had seen a growth of 0.46% in loan book between the January-March and April-June quarters last year. On a year-to-date basis, SBI's credit growth fell more than 2%, Bank of Baroda's credit growth contracted 4.71% and Bank of India's credit growth shrank about 3%. SBI chief Arundhati Bhattacharya said the bank's year-to-date credit growth fell as the bank focused on ‘A’ rated customers. About 90% of the loans in the quarter were given to high-rated companies. "Part of this was a conscious decision and part of it is because we actually did not get good fresh proposals in the quarter," Bhattacharya said.According to bankers, while part of the credit contraction is due to the economic slowdown, capital constraints and reluctance to take on excessive risk has also played a role. "Most of the PSU banks are facing pressure on capital adequacy. It is challenging to maintain 9% core capital adequacy. The pressure on monitoring capital adequacy and maintaining capital buffer is so strict that you cannot grow aggressively," said Rupa Rege Nitsure, chief economist at Bank of Baroda.Nitsure said capital conservation pressures will substantially cut down "irrational expansion of loans" in some smaller banks, which used to grow at a rate much higher than the industry average. The companies coming to banks, in turn, will have to make themselves more creditworthy for banks to lend. "The conservation of capital is going to inculcate a lot of discipline in both banks and borrowers," she said.For every loan that a bank disburses, some amount of money is required to be set aside as provision. Lower the credit rating of the company, riskier the loan is perceived to be. Thus, the bank is required to set aside more capital for a lower rated company than what it otherwise would do for a higher rated client. New international accounting norms, known as Basel III norms, require banks to maintain higher capital and higher liquidity. They also require a bank to set aside "buffer" capital to meet contingencies. As per the norms, a bank's total capital adequacy ratio should be 12% at any time, in which tier-I, or the core capital, should be at 9%. Capital adequacy is calculated by dividing total capital by risk-weighted assets. If the loans have been given to lower rated companies, risk weight goes up and capital adequacy falls.According to bankers, all loan decisions are now being assessed on the basis of the capital that needs to be set aside as provision against the loan and as a result, loans to lower rated companies are being avoided. According to a senior banker with a public sector bank, the capital adequacy situation is so precarious in some banks that if the risk weight increases a few basis points, the proposal gets cancelled. The banker did not wish to be named. One basis point is one hundredth of a percentage point. Bankers add that the Reserve Bank of India has also started strictly monitoring how banks are utilising their capital. Any big-ticket loan to lower rated companies is being questioned.In this scenario, banks are looking for safe bets, even if it means that profitability is being compromised. "About 25% of our loans this quarter was given to Navratna companies, who pay at base rate. This resulted in contraction of our net interest margin (NIM)," said Bank of India chairperson V.R. Iyer, while discussing the bank's first quarter results with the media. Bank of India's NIM, or the difference between yields on advances and cost of deposits, a key gauge of profitability, fell in the first quarter to 2.45% from 3.07% a year ago, as the bank focused on lending to highly rated customers.Analysts, however, say the strategy being followed by banks is short-sighted. "A high rated client will take loans at base rate and will not give any fee income to a bank. A bank will never be profitable that way. Besides, there are only so many PSU companies to chase. All banks cannot be chasing them all at a time. Fact is, the banks are badly hit by NPA and are afraid to lend now to big projects. They need capital, true, but they have become risk-averse," said a senior analyst with a local brokerage who did not wish to be named.Various estimates suggest that Indian banks would require more than Rs. 2 trillion of additional capital to have this kind of capital adequacy ratio by 2019. The central government, which owns the majority share of these banks, has been cutting down on its commitment to recapitalize the banks. In 2013-14, the government infused Rs. 14,000 crore in its banks. However, in 2014-15, the government will infuse just Rs. 11,200 crore.Which of the following statements is correct according to the passage?
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