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University Degree: Microbiology
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Introduction to Spectrophotometric Analysis - By using spectrophotometric analysis or spectrophotometry, one can determine the identity in terms of structure and species of a biomolecule as well as establish the concentration of a certain biomolecule
Beer-Lambert law can be represented by two of the equations shown below: (1) A = ?cl ? = constant extinction coefficient This is the molar absorptivity of the components of interest. It is a constant which is determined experimentally, dependent on the wavelength and compounds of interest. The commonly used unit is M-1 cm-1 (Mikulecky, Gilman & Brutlag, 2009). c = concentration of the sample Sample concentration is often in the unit of molar (M), which is mol L-1 l = pathlength Pathlength is the distance that the light path needs to travel through the sample.
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As the disease progresses further the alveoli proceeds to have an unusual shape due to the continued enlargement of the air sacs, because of this, during exhalation there is great difficulty in airflow since the alveolar walls have been damaged making it difficult to breathe out. Furthermore the elastic connective tissue which helps support the alveoli in place also contributes to the difficulty in breathing since it has been destroyed (Handford et al., 2004). The clinical features of emphysema involve the deterioration of the alveoli which include the alveolar walls losing its structure (Chakir et al., 2008).
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Bacillus megaterium is a gram-positive rod shaped bacteria that produces spores. This type of bacteria is one of the largest Eubacteria that is found in soil (Kunkel, 2009). Clostridium sporogenes is a gram-positive rod shaped bacteria that also produces spores. It is found often in soil as well as the intestines of animals and humans. This type of organism is often used to conduct studies involving low acid foods (Kunkel, 2007). In this lab we will explore three major types of differential staining techniques. These techniques are gram stain, acid-fast stain and the spore stain.
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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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This may include processes such as mitosis, phagotycosis and other forms of transport within the cell. Even though microscopes aid in viewing cellular content what can be seen my be limited due to the sizes of the actual organelles, or the types of stains used to highlight organelles within the cell. For example mitochondria cannot be seen with a standard lab light microscope. When scientist want to view the contents of a cell there are 2 main types of microscopes they use Light and Electron. All depending on the budget they have and the detail needed will determine which they would use.
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The aim of this investigation is to make a series of dilutions using the correct liquid handling technique with a pipette, and then finding out the optical density for each of the solutions when they are pipetted into a 96-well plate.
This type of pipette is useful since they can be used to pipette very small sizes of liquid (ranging from ml to �l). In order to obtain excellent results the user must always make sure that the pipette is held in a vertical upright position and that the right measurement was used. The plastic tips can be used over and over again since they are disposable. Hypothesis: Null Hypothesis: There will be no significant difference between the pipetted dilution samples and the optical density of each well.
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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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Identification of an Unknown Enterobacteriaceae. The purpose of the experimental determination of an unknown was to demonstrate the utility of many tests that indicate the metabolic behavior of the unknown.
It has been shown that its optimal growth temperature was at 37 C. P. vulgaris is a chemoheterotroph, which means it uses carbon sources like glucose for energy and carbon. As a chemoheterotroph, it ferments glucose but not lactose or mannitol. However, because it is a facultative anaerobe, the glucose fermentation only occurs in anaerobic conditions. If placed in non-ideal, aerobic conditions, the microbe will use a variety of organic molecules to survive. (Struble, et al., 2009) When identifying the microbe, several tests can be used. It will test positive on the citrate test and urease test.
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No other life forms are as important as microorganisms for the support and maintenance of life on Earth�. Perhaps the most commonly used bacterium in the laboratory is Escherichia coli due to its incredibly fast generation time of 20 minutes when grown in a pure culture under optimal conditions�. The main bacteria utilized in this practical was Bacillus subtilis, a Gram positive bacterium, measuring about 1�m in diameter. This bacterium is in the genus Bacillus which are rod-shaped bacteria and are either aerobic or facultatively aerobic� but under certain conditions, can also be anaerobic. They are widely found in soil and water and are able to form endospores under adverse environmental conditions.
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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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(Davidson, 2010) After inoculation, the tubes are incubated at 37�C which is the optimal temperature for growth. A negative result for the carbohydrate test is no change in pH(no colour change) or gas production. (Goldman 2009) A positive result is gas produced and a acid production (yellow). (Goldman 2009) The second test is the indole test. Indole is a by-product of the metabolic breakdown of the amino acid tryptophan by the enzyme tryptophanase. (Davidson, 2010) Another by-product of this degradation is pyruvate which is used as an energy source for the bacteria.
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DNA Damage and Nucleotide Excision Repair. With the frequent occurrence of changes in a cell it is important to have DNA repair mechanisms like NER, to prevent mutations, cancer, and the death of the cell or organism.
, 2004). For the genetic information within DNA to remain uncorrupted, it is vital that any chemical changes made to the DNA of a cell be repaired in order to continue proper cell function. Not repairing DNA results in mutation, cancer, and the death of the cell or organism (Sancar et al. , 2004). The damage DNA of an organism contains DNA system repairs that stimulate cell responses to deal with numerous DNA damages by eliminating them (Sancar et al. , 2004). One of the many DNA repair mechanisms in living organisms is Nucleotide Excision Repair, otherwise known as NER.
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In this essay I am going to explore the functions of carbohydrates within the body and plants. It will give me a chance to explain and understand fully the role of carbohydrates and, how the structure of a carbohydrate can help the structure of a cell
They also provide an "excellent source for the many different activities going on in our cells". Not only are carbohydrates an excellent source of energy, they also allow cells to communicate with on another, and also bind together with the surroundings of the cell. Carbohydrates are divided into three groups, which are commonly known as "monosaccharides"(single sugars), "disaccharide's" (double sugars), and "polysaccharides" (many sugars). Oligiosacchaides, are when only few monosacchardies units are linked together, they are still however very important.
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Folic acid. In 1993 the Food and Drug Administration (FDA), in the USA suggested the regulation of fortification of folic acid in many different types of food. Since then, only 10 countries have adopted this idea to fortify their staple foods. This would
It was synthesised by the Americans naming it the chemical name pteroylglutamic acid. Folic acid is water soluble therefore it is referred in use then naturally occurring Folate, which has a lower absorption rate. Folic acid is also involved in the function of nucleoprotein synthesis, and red blood cell synthesis. A deficiency in this vitamin can lead to anaemia, and neural tube defects in the foetus. In the colon there are large numbers of bacteria. These bacteria aid in digesting the remaining food products. They also produce folic acid, which prevents anemia, and they aid in the absorption of several vitamins.
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This review looks at how silicification of bacteria allows preservation of the bacteria through fossilisation and also helps the bacteria to survive the hostile environment.
Moreover, modern geothermal technology allow for contemporary analogues for conditions which Precambrian microorganisms are fossilized.  There are many researches that detail the silicification of microorganisms as preservation. For example, a thin microbial mat formed by 0.25-�m diameter filaments was silicified on the top of volcanic littoral silts, [11, 12] and similar silicified microbial mat remnants was found in other parts of South Africa.  Further evidences include silicified colonies of small (<1 lm) coccoidal micro-organisms associated with 3.466 Ga-old volcanic sands and silts  and fields of small, silicified stromatolites with dissimilar morphologies were found in Australia.
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Indole is a compound derived from the amino acid tryptophan. A broth of tryptone is inoculated with two loopfuls of each bacterium. If the bacterium is one which converts tryptophan to indole, a red surface layer appears upon addition of dimethyl-aminobenzaldehyde, more commonly known as Kovac's reagent. Otherwise, the colour of the broth will remain completely yellow (Madigan et al, 2009). In the urease test, a urea broth, yellow before incubation, is inoculated with two loopfuls of each bacterium. If the broth, after inoculation, increases in acidity, the colour changes to pink with the presence of a phenol red indicator.
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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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Write an essay in up to 2000 words on the following topics, describing the procedures that can be used to isolate proteins from a cell and the methods involved in checking the purity. Using diagrams to help, you should explain fully the principles behind
In Healthcare the main procedures used are: 1. Percipation 2. Chromatography 3. centrifugation In healthcare cells are very important as they carry important information about the human body, as most disease is discovered in the blood as cells are infected. The isolation of proteins from cells is very important as we are able to examine and treat infections, viruses etc. with the growing technology in healthcare and treatment becoming widely available the isolation techniques vary. Infections associated with health care are a growing factor as they can live in the body undetected for a long time, however the detection of these infections is vital so that we can treat them successfully, the cells contain different proteins therefore the correct method is necessary.
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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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tuberculosis. � Usually pulmonary infection - at periphery of mid zone of lung (sub-pleura) � TB bacilli are engulfed by macrophages - those survive multiply in macrophages ? carried to hilar lymph nodes � Dissemination to other organs through blood stream can occur Cell mediated immunity & Hypersensitivity � Develop 2-6 weeks after infection.
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- Then after purification of restriction enzyme further manipulation of DNA has been developed. Restriction enzyme has been isolated from bacteria , it cuts DNA at a specific sequence and produce restriction fragments . it has two major roles which is construction of recombinant DNA molecule and maps the restriction sites place in DNA . - Southern blotting developed by Edward M. Southern at Edinburgh university in the year 1970. This locates an interested DNA sequence within a complex mixture by using radioactive probes to detect fragments on agarose gel which are complementary to a sequence of a given DNA.
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The electrical potential across the cardiac cell membrane called resting membrane potential which is (-90mV) in atrial and ventricular myocardial cells and (-70mV) in the SA and AV nodes. When electrical impulses activates myocardial cells the membrane of polarized myocardial cells will turn to open the Na+ channels leading to flow in the sodium ions from out side of the cells in to the cells with their ionic concentration gradient, thus the interior cell become less negative with respect to it is exterior and the cell membrane potential decreases to (-65mV to -70mV)
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After which the filter is incubated in a solution that contains the labelled probe in the hybridisation step3. It is usually carried out overnight but in some cases between 1-48 hours3. After hybridisation, the filter is washed to remove the probe and the stringent of the washing can be altered so that only probe molecules that are completely base-paired with the immobilised target are left on the filter or that the probe molecules that have hybridised to related sequences forming duplexes that contain mismatches are also left on the filter3. Such washing of filter may take about 30-60 minutes3.
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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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Managing Fusarium wilt disease is a achieved through chemical soil fumigation and resistant cultivars. Now there are available broad spectrums of biocides used to fumigate soil before planting as Captan, Benomiel and other commercial varieties ( Fravel et al., 2003) But they are have a negative impact on the environment . The environmentally save method is the use of BCAs. But[W2] resistance breeding are very difficult when no dominant gene is known (Fravel et al., 2003). Further more the pathogen can overcome the plant resistance. Virulent races of F.oxysporum f.sp. ciceris have undermined the importance of resistant cultivars of chickenpea ( Haware and Nene 1982).
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