What do chromotography, and reagents, mean?
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I ll guess\nchromo in greek means color\ngraphy is a kind of analysis\nso chromotography may mean color analysis\nV the Greek
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lol, last minute lab write ups. afaik enzymes dont change colour, as they are not supposed to change so id bet there is something else that the enzyme works on. better put up the other reagents to get a better answer
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Volumetric Analysis also known as Titration is a standard laboratory method of quantitative/chemical analysis which can be used to determine the concentration of a known reactant. Because volume measurements play a key role in titration, it is also known as volumetric analysis. A reagent, called the titrant, of known concentration (a standard solution) and volume is used to react with a measured volume of reactant (Analyte). Using a calibrated burette to add the titrant, it is possible to determine the exact amount that has been consumed when the endpoint is reached. The endpoint is the point at which the titration is stopped. This is classically a point at which the number of moles of titrant is equal to the number of moles of analyte, or some multiple thereof (as in di- or tri- protic acids). In the classic strong acid-strong base titration the endpoint of a titration is when the pH of the reactant is just about equal to 7, and often when the solution permanently changes color due to an indicator. There are however many different types of titrations.\n\nMany methods can be used to indicate the endpoint of a reaction; titrations often use visual indicators (the reactant mixture changes colour). In simple acid-base titrations a pH indicator may be used, such as phenolphthalein, which turns (and stays) pink when a certain pH is reached or exceeded. Due to the logarithmic nature of the pH curve, the transitions are generally extremely sharp, and thus a single drop of titrant just before the endpoint can increase the pH by several points - leading to an immediate colour change in the indicator. That said, there is a slight difference between the change in indicator color and the actual equivalence point of the titration. This error is referred to as an indicator error, and it is indeterminate.\n\nEtymology\nThe word "titration" comes from the Latin "titalus," meaning inscription or title. The French word, titre, also comes from this origin, meaning rank. Titration is by definition the determination of rank or concentration of a solution, so it corresponds.\n\nPreparing a sample for titration\nTitrations are performed "in solution". If the sample isn't a liquid or solution the samples must be solved. If the analyte is very concentrated in the sample it might be useful to dilute the sample.\n\nAlthough the vast majority of titrations are carried out in aqueous solution, other solvents such as glacial acetic acid or ethanol (in petrochemistry) are used for special purposes.\n\nA measured amount of the sample can be given in the flask and then be solved or diluted. The mathematical result of the titration can be calculated directly with the measured amount. Sometimes the sample is solved or diluted beforehand and a measured amount of the solution is used for titration. In this case the solving or diluting must be done accurately with a known coefficient because the mathematical result of the titration must be multiplied with this factor.\n\nA lot of titrations require buffering to maintain a certain pH for the reaction. Therefore buffer solutions are added to the reactant solution in the flask.\n\nSome titrations require "masking" of a certain ion. This can be necessary when two reactants in the sample would react with the titrant and only one of them must be analysed. Or when the reaction would be disturbed or inhibited by this ion. In this case another solution is added to the sample which "masks" the unwanted ion (for instance by a weak binding with it or even forming a solid insoluble substance with it).\n\nSome redox reactions may require heating the solution with the sample and titration while the solution is still hot (to increase the reaction rate).\n\nProcedure\nN.B. Before starting, make sure that all of your glassware—especially the burette—is clean and dry. Alternatively, you can rinse out the glassware with the solution that is to be stored in the particular piece
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Either:\n\n(a) you're not getting a very clean separation, as the peaks should be vivid\n\nor\n\n(b) your detector is insuitable for the acids you're studying.\n\nAtleast, that's my analysis. Any A-Chem experts here?
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well, you kinda answered your own question. The laser optics refers (here) to the use of mirrors to focus the light on the sample, this is normally used for a fluorescent dye which has been used to stain a part of the cell.
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I have recently wondered the answer to this question myself.  I think that passive dyes, such as ROX, constantly emit a flourescent signal.  This signal is not supposed to be influenced by the PCR reaction cycle (ie "passive").  I believe the ROX dye is a rhodamine labeled amino acid, or maybe a short peptide. Other passive dyes are probably similar.
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Sounds like a typo.  Call the lab that performed the test.
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The reagents table\nThe reagents for each molecule in the subset are looked up in a reagents table, wherein each reagent may be assigned various properties, as follows:\n\nReagent Name: Unique name for each specific reagent. The name will be used as the key for the lookup to link Rgroup fragment names in the Study Table or BDF file with reagents in the reagents table \n\nMW: Molecular weight for each reagent. \n\nSupplier: Name of the specific supplier. \n\nCost: Monetary cost of a specific reagent. Cost should be normalized so that all entries in the reagents table refer to cost per unit weight, usually per gram. \n\nReagent Penalty: A number with integer values from 0 to 10 representing a preference for a specific reagent. Smaller numbers are better: a reagent with a penalty = 0 is preferred over a reagent with a penalty = 10. This field can be used to penalize reagents based on the presence of particular functional groups or substructures, ease of synthesis, chemist bias or intuition, etc. (data type: integer).
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"Reagent Grade" means that a chemical meets standards established by the American Chemical Society with regard to purity.  R.G. chemicals are normally what one uses in the laboratory.  "Technical Grade" is the grade of chemical normally used in industry.  Such chemicals may contain impurities that can make them unsuitable for lab use.
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Quantitative = amount \nSpectrophotometric = wavelength specific measurement\nAnalysis = determination\n\nCombining these terms gives you "the determination of the amount of material present by the use of specific wavelengths of light".\n\nMany compounds have chromophores, or specific portions of the molecule, that absorb energy of a specific wavelength.  Therefore, using a spectrometer, you can determine that a light source produces a given amount of energy at some predetermined wavelength.  When the analyte of interest is inserted into the light path, some of the energy will be absorbed, which will be proportionate to the amount of material present.  (Increasing the amount of material will absorb more energy, decreasing the amount of material will absorb less energy.)\n\nBy comparing the unknown material to a series of samples prepared in known concentrations, you can determine the concentration (amount) of the unknow sample.  The actual formula for this process is known as the Beer-Lambert Law.
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Hi.  I found a link to which will help you answering your question.\n\nThis is not my field of expertise, but I'm guessing the darker sections indicate heterochoramtin.  This is the portion of the chromosome that not currently being used for expression of proteins.\n\nHope this helps.  Pass on the good karma!
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Fluorometry is the measurement of light emitted, for example, by a labeled sample that has been excited by light at a shorter wavelength. The greater the difference in wavelength between the excitation and emission light (this difference is known as the Stokes’ shift) the greater the potential for sensitive measurement of the fluorescence. \n\nTime-resolved fluorometry is possible when the fluorescent label has a long decay time. Light is collected at a time when non-specific fluorescence from the sample matrix and the microplate, etc. has died down. The elimination of interfering background in this way makes a further big contribution towards sensitivity. The DELFIA method exploits the unique fluorescence properties of lanthanide chelate labels. These labels have a long decay time as well as a wide Stokes’ shift.
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temperature changes de amount of energy in molecules, which has a direct efect on the amount of light transmited through a  solution and, therefore, afects absorbance.  Also, in chemical analysis, the formation of colored compunds is necesary and if the correct temperature is not set, the compound doesn't form correctly. (just some reaction mechanisms from organic chemistry)\nThe AOAC method for testing nitrate content in water is a good example. If you don't give the reaction the correct temperature, the colored compound will never form and the test is invalid.
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The UV-VIS spectrum is due to the electronic transitions of the molecule. This is characteristic of a compound. Qualitative and quantitative estimations of compounds are possible by this non destructive technique. \n\nThe absorption (A) of a solution at a particular wavelength is given by Beer-Lambert's law ect = A where c is the concentration of the compound , t is the thickness of the cell and e is the molar extinction coefficient characteristic of the compound at a given wavelength. This principle is used for quantitative measurements. \n\nCary 5E is a high resolution spectrophotometer to study the electronic spectrum of solutions, single crystals and powder samples (in nujol mull) in the range of 3150-185 nm. This is a double beam instrument controlled by a microprocessor. Base line correction, repetitive scan, kinetics, derivative and concentration modes are possible. Diffuse reflectance is available for solid samples. VT accessory in the range 5-90 degrees Centigrade is available\n\nThis principle is used for quantitative measurements.
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See if these fit\n\n1) bright field\n\n2) cilia\n\n3) contrast? = staining
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It is called mitosis and the stage where you could see pairs of doublestranded chromos. would be in Prophase.
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liquid chromatography  separates by charge at a given pH\ngel chromatography  separates by size\n\nthen there is electrophoresis\n\nNow would be a good time to point out I failed one biochemistry exam 4 times\n\ngood luck.