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University Degree: Microbiology

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  1. Describe the processes used to extract copper and gold from their ores using bacterial leaching - In each case, explain how the micro-organisms liberate the metal from its ores and describe how the metal is then extracted from the mixture.

    Thiobacillus attached directly to the mineral surface * Indirect Mechanism: - In indirect mechanism, bacteria do not need to be in contact with mineral surface. (200 words) Extraction of metal (Copper & Gold) from its ores:- Crushing & Grinding:- The ore is put into mills with liquid (mostly water). The mill rotates causes ores and liquid to crush against one another, which breaks the ores into smaller pieces. The solution after crushed and grinding is called slurry. Flotation &Thickener:- Liquids called reagents in which one attracts metal and other makes bubbles are added to the slurry in a large container in the presence of air.

    • Word count: 1492
  2. The role of ATP and NAD / FAD in Respiration.

    * A small number (some 5-10) circular molecules of DNA The glycolytic Pathway Glycolysis is the splitting, or lysis of glucose. It is a multi-step process in which a glucose molecule with six carbon atoms is eventually split into two molecules of pyruvate, each with three carbon atoms. Energy from ATP is needed in the first steps, but energy is released in later steps, when it can be used to make ATP. There is a net gain of two ATP molecules per molecule of glucose broken down.

    • Word count: 837
  3. Separations in paper chromatography involve the same principles as those in thin layer chromatography.

    The chamber should be saturated with the developing solvent to achieve high resolution. Discussion: When the leaves of green plants are extracted, a complex mixture of components is obtained. The components that are obtained include anthocyanin, chlorophyll a and b, carotenes, and xanthophylls. If you try to extract these components from the green leaves by using water, the extraction is rather ineffective. This is because water is a polar compound and these components are nonpolar compounds. Therefore, water can't effective dissolve them out of the leaves (remember: like dissolves like).

    • Word count: 829
  4. Mining process of copper.

    The process was incedentally discovered when a blue-green solution was discovered near mine wastes. On investigation, although aberrant, the solution occured naturally through the work of micro-organisms. There were two types: Thiobacillus ferro-oxidans - which oxide the Fe2+ ions; and thiobacillus thio-oxidans - the S2-. Biotechnologists soon discovered that spraying the low-grade ores with the micro-organisms could be used to extract copper. The low- grade ore and tailings left from any previous mining is piled up (1). The ground below is impermeable, allowing the solutions to drain away. The pile is then sprayed with the micro- organisms, who thrive in the acidic environment.

    • Word count: 1185
  5. Copper can be extracted from low-grade ore (CuFeS2) by means of bacterial leaching.

    The Fe2+ and Fe3+ ions are left behind in the aqueous solution. A compound that is a good ligand for copper ions is dissolved in an organic solvent immiscible in water, such as kerosene. When this solution is mixed with the copper ions dissolved in water, this reaction takes place: Cu2+(aq) + 2LH (organic) ? CuL2 (organic) + 2H+(aq) L = Ligand This process moves the copper ions from the water, where they are at a low concentration, to the organic solvent, where they are at a high concentration. After the copper ions have been removed the remaining Fe2+ ions and Fe3+ ions are oxidised in an open pond with the T.

    • Word count: 1101
  6. Essay Writing On The Formation Of A.T.P

    The ATP basically lowers the activation energy in order to make the reaction more efficient. The glucose phosphate is further phosphorylated in order to produce fructose bisphosphate, using ATP, again for the same reason as above. At this stage, all the molecules produced are still 6 carbon molecules. Once the fructose bisphosphate has been produced, it then reacts and splits into two separate molecules of glycerate-3-phosphate, which is a 3 carbon, chained molecule. For the final stage of the process of glycolysis the molecule glycerate-3-phosphate is oxidised by a coenzyme, NAD.

    • Word count: 799
  7. How does varying bacterial amylase effect inhibition by copper?

    Bacteria can be found in a wide range of environments, for example, water, air, soils and sediments. Bacteria are also found in a wide range of temperatures from 0-90 �C. The bacteria have adapted to the environments. Therefore I think that bacterial amylase have a better chance at withstanding changes in temperature and pH and therefore will be more resistant to denaturation. The rate of reaction will increase as the temperature increases. This is because the molecules have more kinetic energy resulting in more successful collisions.

    • Word count: 2462
  8. Bacterial Leaching in the mining industry

    A traditional method of extracting this gold is to use froth flotation to separate the refractory minerals from any unwanted oxide ores and non-metallic minerals present. This produces a sulphide concentrate, which is then roasted to liberate the gold. The gold is extracted by treating the resulting mixture with an aerated solution of sodium cyanide, a process called cyanidation. However, roasting converts any sulphur in the refractory minerals to sulphur dioxide and any arsenic to arsenic (III) oxide, both of which have environmental pollutant qualities.

    • Word count: 1057
  9. Assess the effect of adjacent pH on the germination of a mustard seed.

    As well as testing the effect of buffers, I am going to do an experiment using water as well. Seeds need water, correct illumination, suitable temperatures and the presence of oxygen to grow. All of these factors have been taken into account, and have been made provision for in my plan: pH is the changing variable in my experiment, and the seeds will receive natural lighting and room temperatures throughout the experiment. Oxygen will be constantly available as the petri dish lids are unsealed and will be removed daily to allow oxygen refreshment.

    • Word count: 1457
  10. To Identify 5 Given Oils By Testing Their Viscosity At Different Temperatures.

    Two smaller molecules are formed. One is still an alkane - a hydrocarbon with only single bonds. The other is an alkene - a hydrocarbon with at least one double bond in its chain. This is said to be unsaturated because extra atoms can add when the double bonds break down to a single bond again. By contrast, alkanes are saturated. Below molecules are shown using structural formulae. Diagram page 112 (Source 1) Addition Polymerisation "The short unsaturated molecules (monomers) can join up with each other when their double bonds break open.

    • Word count: 1410
  11. Bacterial Leaching

    It is then mixed with the solution containing the Cu2+ ions the ligand then binds with the Cu ions as below. Cu2+ (aq) + 2LH (organic) CuL2 (organic) + 2H+ (aq) This process can then be reversed by mixing the organic solution with a small amount of concentrated acid. This pushes the Cu2+ ions into the solution containing the acid gaining a further increase in the concentration of Cu2+ ions. Both of these processes depend on the pH. The leftover solution then goes to an open pond where t. ferro-oxidans catalyses oxidation of the remaining Fe2+ ions to Fe3+ ions.

    • Word count: 975
  12. “Additional Polymerisation, monomers join together without the loss of atoms from the molecule.”

    Here is an example of a common inhibitor: Benzoyl Peroxide (Reference 4 ) The radical now combines with the spilt carbon-carbon double bond. The new radical continues to react with more alkenes and hence the chain grows. Eventually two free radicals collide producing a final molecule, as this has a random timing the chain lengths can vary from 2000 molecules to 20000. However, a chain can also combine with another growing chain if they were to rub together causing a bond to form between two carbons.

    • Word count: 1023
  13. The Energy Levels of Molecules

    S p d f P 6 6 - 7 18 (2n2 = 72) S p d * Q 7 7 * *Man-Made * Elements S * Kinetic Energy There are three different forms of Kinetic Energy in molecules, as follows: > Translational Energy - This is when single diatomic molecules move at a certain velocity in a straight line. > Rotational Energy - This is when single diatomic molecules can rotate around their centre of gravity. > Vibrational Energy - This is when single diatomic molecules at the end of the bonds can move relative to each other.

    • Word count: 1752
  14. How is NADPH produced in (a) Photosynthetic AND (b) Non-photosynthetic cells? How and where are ketone bodies (a) synthesised AND (b) utilised?

    NADPH is used in the Calvin cycle, which takes place in the stroma of chloroplasts and synthesises hexoses from carbon dioxide and water. In order to oxidise NADPH by this process, ribulose 5-phosphate is first phosphorylated by R5P kinase to generate ribulose-1,5-bisphosphate. This is carboxylated and broken down by CO2 to give two molecules of 3-phosphoglycerate in a reaction catalysed by the enzyme Rubisco, and which features two intermediates ? one highly unstable and the other an enediolate. The enediolate forms first as the ketone group on R-1,5-BP is reduced, before carboxylate adds to form the unstable intermediate which immediately breaks down via hydrolysis to give two 3-phosphoglycerates.

    • Word count: 1091
  15. Compare and Contrast Eukaryotic and Prokaryotic Cells

    whereas eukaryotic cells, if they have a cell wall, have one made of cellulose[c]. Prokaryotic cells may also have a slimy capsule around the cell for protection. Genetic material Another major difference between the two types of cell is that prokaryotic cells do not have a nucleus or other membrane bound organelles whereas eukaryotic cells do ? instead the genetic material of prokaryotes (a single plasmid [d]as opposed to several chromosomes) is in a region of the nucleus called the nucleoid. The genetic material in eukaryotic cells is associated with the histone protein, whereas that of prokaryotic cells is folded around several different proteins including the HU protein.

    • Word count: 915
  16. Mast Cell Degranulation Practical

    & Louie, S. G. 1999). Therefore after careful observation, I can clearly see that there is not much difference between the control and the cells treated with SCG or Salbutamol. The cells that gave the highest percentage for degranulation score ++ was the 48/80 treated cells (39.53) and they gave a percentage of 36.79 for partial degranulation. This was also expected since the polymer 48/80 triggers degranulation in mast cells. 2. The class results agree with my prediction to an extent as I predicted that when 48/80 and SCG were added to the cells, then there would be a higher

    • Word count: 645
  17. The objective of this lab was to determine if different cultures would successfully grow on diverse agar medias and to distinguish the appearance of growth on the mediums.

    The Tryptic Soy Agar was used as the enriched media in this experiment. TSA was mainly used as a control for growth medium. It was also used to observe colony morphology, to develop a pure culture and to achieve adequate growth for further testing (Liu, 2005) In this experiment, we transferred the four liquid broth cultures onto each of the Agar plates using a sterile cotton swab. We dipped the swab into the broth once and created a stroke, 2 cm long, on each of the agar plates in a specific order.

    • Word count: 1069
  18. nasal carriage of s.aureus

    Here different media and staining will apply to identify the organism. Method: for material and method the lab manual was followed. Result : Table 1 : Identification of organisms from the nasal swab in class 1. Identification technique appearance Results Gram stain Mixed(purple and pink) Gram positive and gram negative cocci are present Table 2: swab from nose to msa and nutrient agar class 2. no name of agar colour of the colony AGI 1 MSA Yellow 2 2 nutrient agar colour less colony 1 Table 3: organism from MSA and nutrient agar to DNA agar.

    • Word count: 821
  19. Development of salmonella vaccine

    Regulatory GMP (Good Manufacturing Practices) requirements are increasing to guarantee the safety of vaccines being developed and produced. Using raw material of animal origin is avoided in the early-stages of research and development. Only few techniques such as nano-filtration and chromatography steps are applicable to viral removal. The worldwide ban of preservatives such as thiomersal raised the standard for sterile production and supported the trend to monodose presentations. To date, vaccines based on three different technologies are registered for human use: (1) whole inactivated vaccines containing entire killed bacteria or viruses, (2) subunit vaccines, containing only the relevant antigens of the pathogens in a highly purified form, and (3)

    • Word count: 2248
  20. Enzymatic Ability of Bacteria Experiment

    For full details of the tests conducted and the theory behind them, please refer to Maddox et al (2012) Fermentation Test This test is designed to see the ability of the microorganism to metabolise carbohydrates. E.coli, P.vulgarus, S.aureus and B.subtilis were inoculated in three different media; sucrose nutrient broth, glucose nutrient broth and lactose nutrient broth. These were incubated for one to two days at 37ËC. Hydrolysis Tests E.coli and B.subtilis were inoculated on a starch agar plate and a skim milk agar plate, and then incubated at 37ËC for two days. The starch plate was flooded with iodine to see if the starch had been hydrolysed to dextrins.

    • Word count: 858
  21. The benefits of bacillus subtilis

    You can find Bacillus Subtilis in soil, decomposing plant matter, water, and air. An interesting feature about Bacillus Subtilis is that it has the ability to produce endospores. Endospores are thick walls that surround the cell to protect its DNA and other internal structures. With that being said, this makes Bacillus Subtilis a very tough bacterium to destroy. Bacillus Subtilis can withstand harsh temperatures, environmental factors, chemicals, extreme pH, and few types of radiation. With the ability to withstand such harsh conditions it is likely to find Bacillus Subtilis to live in many extreme habitats such as desert sands, hot springs, and Arctic soils.

    • Word count: 978

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