How do some enzymes exhibit faster-than-diffusion kinetics?
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Quantum tunnelling ( passage of electrons/atoms through a potential energy barrier and/or other matter .... it's a probability thing ) has been suggested as a possible reason.
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B, its specific shape allows specific substrates to bind to the enzyme, thus catalyzing the reaction. If the enzyme DIDN'T have the specific shape, then the substrate would have to take a longer time to break their own bonds themselves.
1100165
Mg is neseccary for the catalytic reaction. A lot of enzymes have an ion in their catalyitic center which usually co-ordinate the reacting groups.
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here're some informative links http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/E/Enzymes.html , http://en.wikipedia.org/wiki/Enzyme\n\nhope this helps.
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If I remember my biology correction, an enzyme is essentially a protien. Protiens look like tangled up strings of spaghetti (and therefore, so do enzymes). Enzymes work by fitting exactly with another molecule. \n\nA denatured enzyme is an enzyme that has lost it's shape for one reason or another. Once an enzyme has lost its shape, it can no longer take whatever action it usually takes. \n\nEnzymes can be denatured by heat or chemically.\n\nHope that helps!
268978
it speeds up the rate of a biological reaction without itself being used up. it acts by binding with the substrate involved in the reaction and converting it into another substance. it is relatively specific on the reaction it catalyses. this is produced within living cells and may act either within the cell or outside it
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facilitated diffusion
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http://www.biologymad.com/master.html?http://www.biologymad.com/Enzymes/enzymes.htm\n\nhttp://www.tvdsb.on.ca/westmin/science/sbi3a1/digest/enzymes.htm\n\nhttp://www.activescience-gsk.com/miniweb/content/enzymes/how_do.htm\n\nI use these websites with my students...it has some basic enzyme info.\n\nAn enzyme is active only when there is substrate present. So therefore, the rate of activity will increase when thre is "something to do!"
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A low pH slows down the enzyme activity. The enzyme present in the stomach is ptyalin. When ptyalin is inactivated, it cannot function.\n\nA little fact of enzyme:\nEnzymes are biological catalysts made of protein. They alter the rate of chemical reactions without themselves being chemically changed at the end of the reaction.\n\nEnzyme combine with the substrate (starch) to form a enzyme-substrate complex. After that, it breaks up into smaller products. The reaction does not change the surface configuration on the enzyme, and therefore can be used to catalyze another reaction. Smaller products makes digestion easier.\n\nSo, when pytalin (enzyme) is inactivated, it cannot go through the procedure as described above.
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It is a type of inhibition that occurs when a molecule, of roughly the same shape of the substrate, enters the active site of an enzyme.  It blocks the active sight and hence prevents the substrate molecule to enter active site.\n\nThe reaction's rate is decreased as not all enzymes can metabolise the substrates, some of them being blocked by the inhibitor.
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Enzymes can only take (generally) very specific substrate.  A dissimilar substrate will usually not undergo any enzymatic alteration.  An enzyme's shape is what determines its function.  Altering the shape of the enzyme will usually prevent it from working on its substrate.
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(m)\n\nmetabolic pathway analysis, it should be considered that many enzymes operate with low specificity (e.g. nucleoside diphosphokinase, uridine kinase, transketolase, aldolase), so that various substrates and products can be converted. Here, we analyze the effect of enzymes with low substrate specificity on the elementary flux modes (pathways). We also study the benefits of two different approaches to describing multifunctional enzymes. The usual description is in terms of (overall) enzymatic reactions. At a more detailed level, the reaction steps (half-reactions, hemi-reactions) of the formation and conversion of enzyme-substrate complexes are considered. Multifunctional enzymes operate according to various mechanisms. This is illustrated here by the reaction schemes for the different enzyme mechanisms of bifunctional enzymes. For enzymes with two or more functions, it is important to consider only linearly independent functions, because otherwise cyclic elementary modes would occur which do not perform any net transformation. However, the choice of linearly independent functions is not a priori unique. We give a method for making this choice unique by considering the extreme pathways of the hemi-reactions system. A formal application of the algorithm for computing elementary flux modes (pathways) yields the result that the number of such modes sometimes depend on the level of description if some reactions are reversible and the products of the multifunctional enzymes are external metabolites or some multifunctional enzymes partly share the same metabolites. However, this problem can be solved by appropriate interpretation of the definition of elementary modes and the correct choice of independent functions of multifunctional enzymes. The analysis is illustrated by a biochemical example taken from nucleotide metabolism, comparing the two ways of description for nucleoside diphosphokinase and adenylate kinase, and by several smaller examples.
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figure out the efgfect of the enzyme. Or you can test DNA structure. Inhibitary enzymes have a blacked actionsite whereas activation enzymes have activation sites open to substrates
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Given that a certain type of molecule is small enough to permeate through the cell membrane, the most important factor influencing the rate of diffusion is the concentration gradient.  This is simply the difference in concentration levels of the substance between the outside and the inside of the cell.  The larger the difference in concentrations, the greater the rate of diffusion.
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The effects of temperature may be explained on the basis of kinetic theory - increased temperature increases the speed of molecular movement and thus the chances of molecular collisions, so within a narrow range (often 0-45 °C), the rate of reaction is proportional to the temperature. It is often said that an enzyme's rate of reaction doubles for every10° C rise in temperature. In this respect, the biochemistry of enzymes is similar to chemistry as studied elsewhere, However, the interaction between this positive effect of increased temperature and the negative effect described below results in a different situation, so that enzymes may be said to have an optimum temperature for their action. \n 4 Above normal temperatures (say 60 °C), heat alters irreversibly the enzyme molecule. This denaturation is due to molecular vibrations (caused by heat) which change the shape of the protein, altering the folding and internal cross-linkages in its polypeptide chains. These changes - especially in the region of the active site - mean that the enzyme is inactivated, even when returned to normal temperature. \nIt would be wrong to say that an enzyme is KILLED by heat, since it is only a molecule, not an organism. \nHowever, misconceptions of this sort are easily spread (see the BASC enzymes booklet!) \n\n\n\nThe higher the temperature to which the enzyme is subjected and the longer the heating is continued, the greater the proportion of damaged enzyme molecules and the result is that the conversion process becomes less and less efficient.\n\n\n\n\n\nBelow normal temperatures, enzymes become less and less active, due to reductions in speed of molecular movement, but this is reversible, so enzymes work effectively when returned to normal temperature.
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The quickest absorption will be of the 2-glucose "polymer."  That way, every cut by the enzyme yields two glucoses.  With any other chain length, each cut would yield one glucose until the last cut, which would yield 2.\n\nAnything wrong with amalyse?
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In the absense of additional information or context the basis for this question rests in the size of the molecule. The smaller molecule will have a greater rate of diffusion than the larger molecule.  In general size of molecules is directly proportional to their molecular weight. When all molecules are the same molecular weight you will need to consider which ones are smaller based on the attractive forces between them. \n\na)  CO and N2 - N2 has a triple bond (the Ns are held closely to each other therefore small) and is very stable and I would bet that it will diffuse faster than CO since its actual size is smaller and because it is stable it is less likely to react with any medium through which it is diffusing.\nb) No2 and SO2 - this is likely to be based on size with the larger SO2 diffusing more slowly.\n\nHope this helps.