Proteins are separated in an SDS-PAGE experiment on the basis of their ?->(Show Answer!)

1. Proteins are separated in an SDS-PAGE experiment on the basis of their

Write Comment

Comments

Tags

Show Similar Question And Answers

QA->Name the digestive enzyme that converts Proteins to peptones is ?....

QA->Name the digestive enzyme that converts Proteins to aminoacids (Peptones) in stomach is ?....

QA->Presence of excess proteins in urine ?....

QA->How much daily intake of proteins is recommended for a moderately active women?....

QA->On the basis of the process of their formation; which soil is formed differently from the other three?....

MCQ-> Analyse the following passage and provide appropriate answers for the questions that follow: Each piece, or part, of the whole of nature is always merely an approximation to the complete truth, or the complete truth so far as we know it. In fact, everything we know is only some kind of approximation, because we know that we do not know all the laws as yet. Therefore, things must be learned only to be unlearned again or, more likely, to be corrected. The principal of science, the definition, almost, is the following: The test of all knowledge is experiment. Experiment is the sole judge of scientific “truth.” But what is the source of knowledge? Where do the laws that are to be tested come from? Experiment, itself, helps to produce these laws, in the sense that it gives us hints. But also needed is imagination to create from these laws, in the sense that it gives us hints. But also needed is imagination to create from these hints the great generalizations – to guess at the wonderful, simple, but very strange patterns beneath them all, and then to experiment to check again whether we have made the right guess. This imagining process is so difficult that there is a division of labour in physics: there are theoretical physicists who imagine, deduce, and guess at new laws, but do not experiment; and then there are experimental physicists who experiment, imagine, deduce, and guess. We said that the laws of nature are approximate: that we first find the “wrong” ones, and then we find the “right” ones. Now, how can an experiment be “wrong”? First, in a trivial way: the apparatus can be faulty and you did not notice. But these things are easily fixed and checked back and forth. So without snatching at such minor things, how can the results of an experiment be wrong? Only by being inaccurate. For example, the mass of an object never seems to change; a spinning top has the same weight as a still one. So a “law” was invented: mass is constant, independent of speed. That “law” is now found to be incorrect. Mass is found is to increase with velocity, but appreciable increase requires velocities near that of light. A true law is: if an object moves with a speed of less than one hundred miles a second the mass is constant to within one part in a million. In some such approximate form this is a correct law. So in practice one might think that the new law makes no significant difference. Well, yes and no. For ordinary speeds we can certainly forget it and use the simple constant mass law as a good approximation. But for high speeds we are wrong, and the higher the speed, the wrong we are. Finally, and most interesting, philosophically we are completely wrong with the approximate law. Our entire picture of the world has to be altered even though the mass changes only by a little bit. This is a very peculiar thing about the philosophy, or the ideas, behind the laws. Even a very small effect sometimes requires profound changes to our ideas.Which of the following options is DEFINITLY NOT an approximation to the complete truth?
....

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
....

MCQ-> The pages of a book are numbered 0, 1, 2 . upto M, M>0. There are four categories of instructions that direct a person in positioning the book at a page. The instruction types and their meanings are : 1. OPEN : Position the book at page No. 1 2. CLOSE : Position the book at page No. 0 3. FORWARD, n :From the current page move forward by n pages; if, in this process, page number M is reached, stop at M. 4. BACKWARD, n : From the current page, move backward by n pages; if in this process, page number 0 is reached, stop at page number 0. In each of the following questions, you will find a sequence of instructions formed from the above categories. In each case, let n1 be the page number before the instructions are executed and n2 be the page number at which the book is positioned after the instructions are executed.FORWARD, 25 ; BACKWARD, 10. which of the following statements is true?
....

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?
....

MCQ->Proteins are separated in an SDS-PAGE experiment on the basis of their....