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University Degree: Microbiology
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Statistics have shown that since the implementation of COSHH work related deaths have decreased over time. In the work year 2002/2003 the death toll was 2261 and in the work year for 2009/2010 this number has dropped to 152.2 The latter still being a high number, the Health and Safety Executive (HSE) have maintained its firm stance behind the use of a COSSH assessment in the workplace to avoid all work related incidents and fatalities, statistics from 2003 -2010 show that is making a difference. The regulations defined by COSHH are broken down into 8 steps.
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Gram-negative bacteria that grow on MacConkey agar do not ferment lactose will appear colourless on the medium whereas the agar surrounding the bacteria remains transparent Selective medium is defined as the culture medium that allows growth of certain types of organisms while inhibiting the growth of other organism. The dyes used in the medium, for example the crystal violet inhibits the microbes from growing. Differential medium is a culture medium that allows one to differentiate between or among different microorganisms based on a difference in colony appearance such of those organisms in the same species but different genus (Vasanthakumari, 2009)
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Materials and Method As per BIOL3141 Infection and Immunity Laboratory Manual 2011 pg 19 -26. Results Part A. The agglutination technique employed presently is the test tube method. Agglutinations were visualised as white particulate matter clumped together at the bottom of the test tubes. The scoring method, from 0 to 4, used presently is that adapted from Olopoenia et al., 1999, where 0 is recorded for no agglutination and 4 for 100% agglutination. Olopoenia et al. 1999 indicates that the smallest quantity of serum that exhibits a score of 2 is considered to be the titre.
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The development of these new plastics is further hindered by the potential economic strain of trying to manufacture these products to meet consumer demand. The price of petroleum-based plastics are significantly cheaper than starch-based plastics and many plastic manufacturers are therefore reluctant to continue the development of these plastics. Environmentalists are also concerned about the development of degradable plastics as they feel that this will interfere with efforts to reuse and recycle, which has only started becoming more widespread in the community.
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B Lymphocytes, secrete antibodies which help detect infection in the human body. We can easily tell if we have B lymphocyte cells, if your body didn't contain B cells, then you would get ill very quickly since your body could not detect infections. B Cell Lymphocytes originate on the bone marrow, which then migrate to the secondary lymphoid tissue. The role of B cells in the Human body is the response to antigens, as defense to the body is crucial; therefore the B cells keep the human body protected from Bacteria, etc.
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It is now allowed to bind to a single-stranded copy of the complete gene1 (fig 2 below). DNA polymerase is added to the gene-primer complex1. The polymerase extends to the primer and replicates the remainder of the target gene to produce a new gene copy with the desired mutation. If the gene is attached to a single-stranded DNA bacteriophage (like M13 phage), it can be introduced into a host bacterium and cloned using the techniques1. This will yield large quantities of the mutant protein1. Fig 2: Site-directed mutagenesis in details1. A synthetic oligonucleotide is used to add a specific mutation to a gene.
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The optimum growth temperature, commonly defined as the temperature at which most rapid multiplication occurs, is often only a few degrees below the maximum (Carpenter, 1972). These cardinal points allow bacteria to be classified according to their growth temperature: Psychrophiles are found in many lakes, streams and uncultivated soils, with their main principle being that they are able to grow at 0oC.Growth temperature ranges have been known to start from as low as -5oC and some facultative Psychrophiles still grow between 30 and 35oC (Carpenter, 1972).
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Approximately 50% of "typical" mineral topsoil comprises a mix of water and air-filled spaces that fluctuate according to prevailing environmental conditions whereas the other 50% is solid minerals and organic matters. These hydrodynamic and atmospheric fluctuations result in a environment that drives the spatial and temporal heterogeneity of microbial diversity in soil and such interaction within and between the physical, chemical and biological components might cause the soil system to change over time . Microorganisms in soils regulate the biochemical transformation in soil and are central to carbon (and nitrogen)
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They only require a supply of Fe2+ ions or S2- ions, oxygen and carbon dioxide. The result of this process is that the copper ore separates out into its different elements. The solution contains Fe2+, Cu2+, Fe3+ and SO42- ions. Copper ions can be selectively removed from a bacterial leaching solution by a process called LIGAND EXCHANGE SOLVENT EXTRACTION. A ligand is a compound with a lone pair of electrons that binds to metal ions. A complex is formed in which the central mental ions are surrounded by a number of ligands. A good ligand compound for copper is mixed with an organic solvent, which is immiscible in water such as kerosene.
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The Effects of Varying Starch Concentration on a Solution of Amylase: Measurement of Enzymatic Rate Changes Using IKI.
Enzymes achieve this by lowering the amount of activation energy needed for anabolic reactions, allowing these reactions to occur as catabolic reactions would. Enzymes are generally large proteins made up of several hundred amino acids, and often contain a non-proteinaceous group called the prosthetic group that is important in the actual catalysis. In an enzyme-catalyzed reaction, the substance to be acted upon, or substrate, binds to the active site of the enzyme. The enzyme and substrate are held together in an enzyme-substrate complex by hydrophobic bonds, hydrogen bonds, and ionic bonds (Nichols and Cholewiak, 1991).
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Within a year however, a penicillin and methicillin resistant Staphylococcus aureus (MRSA) strain was described. Subsequently, vanomycin has been used in the fight against MRSA but recently vanomycin resistant S. Aureus (VRSA) have also been identified. Unlike MRSA, VRSA is not so widespread.1 S. Aureus is capable of causing a wide range of infections including skin and wound infections and bacteraemia, thus, untreatable MRSA infections pose a particular risk to the more immuno-compromised, such as critically ill patients.1 Unfortunately, we humans have contributed ourselves in making antibiotic resistance into a health risk.
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But there is no oxidation so no speedy release of products. The inhibition is called competitive because if you increase the ratio of succinic to malonic acid in the mixture, you will gradually restore the rate of catalysis. At a 50:1 ratio, the two molecules compete on roughly equal terms for the binding (=catalytic) site on the enzyme. Link to a quantitative treatment of competitive inhibition. Enzyme cofactors Many enzymes require the presence of an additional, nonprotein, cofactor. * Some of these are metal ions such as Zn2+ (the cofactor for carbonic anhydrase), Cu2+, Mn2+, K+, and Na+.
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Relate the rates of evaporation of three liquids to the degree of intermolecular bonding within the liquid.
As molecules absorb heat from their surroundings to evaporate, they also decrease the temperature of the surrounding because they absorbed all the heat energy. This means that evaporation is an endothermic process. So, when the most energetic molecules jump off into the air, the cooler molecules are left behind with less energy. All together, the surroundings become cooler during evaporation. That is why the thermometer gets cooler in the lab. So, the final temperature of the substances was less than the initial temperature since the most energetic molecules are gone.
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The more H2O2 molecules there are, the less likely is it that CuSO4 (inhibitor) molecules will bind with active site. This is because I expect CuSO4 to either inhibit or inactivate the catalytic activities of Catalase. Biological Principal Enzymes are biological catalysts that make possible chemical changes under the condition in cells. They are globular proteins and are coiled into a precise, three-dimensional shape, with hydrophilic R groups on the side of the molecules enabling them to be lobule in water. Enzymes work by binding to their substrate molecules at their active site, as the enzyme (E)
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"So many peptides, so few grooves" - compare the ways in which specific antigen recognition is accomplished by MHC molecues, by T cell receptors and by antibody molecules.
One way in which the molecular interaction between peptide and MHC has been studied is by introducing mutations in an immunogenic peptide. With this technique, it is possible to identify certain residues that make contact with the MHC molecule and others that are essential for TCR recognition. Together with the evidence presented above, this has lead to the idea that MHC molecules only recognize certain anchor residues of the bound peptide. Typically, a MHC I molecule has been found to have six pockets (A-F)
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If the concentration is greater between the two regions, then the rate of diffusion is also increased. 2} The distance over which diffusion takes place, the shorter the distance between the two regions of different concentration the greater the rate of diffusion. The rate can then be said directly proportional to the diameter of the organism. 3} the area over which diffusion takes place. The larger the surface area then the more molecules or ions can travel at any one time, therefore the faster the rate of diffusion. 4} Variations in the cells membrane may affect diffusion as well.
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aureus strains are resistant to penicillin, ampicillin, and the antipseudomonas penicillins (Neu 1065). Staphylococcus aureus can cause deadly infections of the skin, heart valves, blood, and bones, and in 1997, three Americans were reported to be infected with strains of it that were resistant to our last line of defense- the antibiotic vancomycin. Methicillin, a semisynthetic penicillin, was created to respond to this challenge. However, in the 1980s, methicillin-resitant S. aureus (MRSA) became a problem as well. Now, MRSA is resistant to all penicillins, cephalosporins, carbapenems, and penems due to a gene that produces a protein capable of bonding to and deactivating the penicillin (Neu 1065). Antibiotics are mostly derived from natural products.
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The wort is sent from the whirlpool via a wort cooler or paraflow to a fermentation vessel. As the wort leaves the paraflow, yeast is added, as well as oxygen to allow the yeast to multiply before fermentation begins. Fermentation. In brewing, fermentation is the conversion of sugar into carbon dioxide gas (CO2) and ethyl alcohol. Enzymes within a yeast cell carry out this process. It is in fact a complex series of conversions that bring about the conversion of sugar to CO2 and alcohol.
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: X size < maxsize buffer' = buffer ? <x?> The new value is appended to the end of sequence buffer. Extracting an item is possible only if the buffer is not empty; the value obtained is the one at the head of buffer: ===BufferOut0 [X]============= UpdateBuffer[X] x! : X buffer = <> buffer' = tail buffer x! = head buffer These schemas represent partial operations: they describe the effect of a succesful insertion and a succesful extraction, respectively. When the operations are not possible, some messages must be produced.
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This glucose is transformed into sucrose and then taken to other parts of the plant cell. The energy that glucose stores cannot be accessed readily by the cell. The process of cellular respiration transfers the energy stored in glucose bonds to bonds in ATP (adenosine triphosphate) so that it can be used more easily by the cell. As many as 38 ATP molecules can be generated by glucose through cellular respiration (Kenyon 141). Our goal was to consider one method by which cells make ATP using energy that comes from breaking down the chemical bonds in glucose.
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and ethanol. The rates of the chemical reactions of fermentation depend on the action of enzymes. The enzymes present in yeast cells are specific and will only catalyse the fermentation of certain sugars and not others. Yeast fermentation gives the following during reaction: C6H12O6-------> 2CH3CH2OH + 2CO2 + energy Enzymes Glucose ---------------> carbon dioxide + ethanol + energy (ATP) (a gas) Material: 1. 5 - fermentation tubes, labeled 1 through five. 2. 5 large test-tubs 3. constant-temperature water bath (37oC)
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1 cm of amylase solution was placed in test-tubes 4, 5, and 6 5. 3 beakers were labeled A, B and C. 6. Beaker A's temperature was about 10oC using ice to water. Beaker B's temperature was 20oC using cold water and beaker C's temperature was about 35oC by heating. 7. Test tubes 1 and 4 were placed in beaker A, test tubes 2 and 5 were placed in beaker B and test tubes 3 and 6 were placed in beaker C.
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Bacterial leaching - The process involved and discusses the advantages and disadvantages of this method of extracting metals from low grade ore.
Solvent extraction techniques are used to recover the copper ions from the solution by a process of ligand exchange solvent extraction. (Article 2) The ligand, dissolved in an organic solvent such as kerosene is immiscible in water. Cu2+(aq) + 2LH (organic) = CuL2(organic) +2H+(aq) (L represents the ligand) The copper is removed from a low concentration in water to a high concentration in the solution. Mixing the organic solution with a small volume of concentrated acid reverses the process and pushes the Cu2+ ions back into the aqueous solution increasing their concentration.
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x x = 0.398/1 100 x 0.398 = 28.46 cm3 salt 1.398 Therefore: 100 - 28.46 = 71.54 acid For the making of the buffer pH 8.8: Equations for the dissociation of ammonia and ammonium chloride respectively: NH3 + H2O - NH2- + H3+O NH2Cl � NH2- + Cl- Using the equation previously stated: 8.8 = 9.3 - log [HA] [A-] 5.2 - 4.8 = - log [HA] [A-] 0.5 = - log [HA] [A-] 10-0.5 = [HA] [A-] 0.316 = [HA] : [A-] CH3COOH + H2O - CH3COO- + H3+O (100 - x)
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This can lead an enzyme becoming inactive. This is known as denaturing. When an enzyme is denatured the tertiary structure is altered, this affects the structure of the active site. If the active site's structure is changed then, following the 'lock & key' theory, it no longer compliments the structure of the substrate and it can no longer bind. No ES complexes are formed and the reaction is not catalysed. At each pH the amount of oxygen evolved increased at a fairly constant rate, producing a reasonably steady gradient, this suggests the rate of catalysation altered very little during the five minutes.
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