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University Degree: Microbiology
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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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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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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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In this essay I will look at the biological significance of polysaccharides, and what makes them significant
Polysaccharides have a general formula of Cn(H2O)n-1 where n is usually a large number between 200 and 500. Starch is a polysaccharide made up of alpha glucose monosaccharides. However the alpha glucose in starch forms two compounds; amylopectin and amlylose. Amylopectin makes up 70 % of starch, it consists of chains of glucose monomers linked with 1,4 glycosidic bonds. However about every 20-30 residus there is a 1,6 bond which results in branches being fromed. Amylose makes up the other 30% of starch, however it is an unbranched linear polymer unlike amylopectin. The monomers are joined in1,4 glycosidic bonds.
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other molecules nearby, the instantaneous dipole may affect them and produce induced dipoles Induces Dipoles: * If an unpolarised molecule finds itself next to a dipole, the unpolarised molecule may get a dipole induced in it * The dipole attracts or repels electrons in the charge cloud of the unpolarised molecule, inducing a dipole in it * A dipole can also be induced by the effect of an instantaneous dipole - this makes it possible for a whole series of dipoles to be set up in a substance that contains no permanent dipoles Dipoles and Intermolecular Forces: * If a
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The aim of this experiment was to observe the movement of water molecules by the process of osmosis between living potato tissues and increasing amounts of glucose solution.
The potato bore was used to bore 6 individual rods of potato. Each potato rod was separately cut into 5 pieces of 1.5cm long length and then these were weighted in groups of 5, (The weights recorded). The groups of 5 rods were then placed into the 6 different glucose solutions with the tweezers; H 0, 0.1 mole glucose, 0.2 mole glucose, 0.3 mole glucose, 0.4 mole glucose, 0.5 mole glucose. Each individual group of 5 rods were left in the different glucose solutions for approximately 2 hours. After the 2 hours each group of 5 rods were dried and weighted accordingly to their groups.
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Their findings were confirmed by Fuller, in which sulphanilamide was isolated from the blood and urine of patients treated with Protosil (Fullerton, 1998). Following the dramatic success of Protosil, a cascade of sulphanilamide derivatives began to be synthesised and tested, by 1948 more than 4500 existed, but only about two dozen actually have been used in clinical practice. The sulpha drugs have proven to be ineffective against certain infections such as Salmonella (Patrick, 2001).
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* CD8+ T cells bind epitopes that are part of class I histocompatibility molecules. Almost all the cells of the body express class I molecules. * CD4+ T cells bind epitopes that are part of class II histocompatibility molecules. Only specialized antigen-presenting cells express class II molecules. These include:dendritic cells, phagocytic cells like macrophages and B cells! CD8+ T cells The best understood CD8+ T cells are cytotoxic T lymphocytes (CTLs). They secrete molecules that destroy the cell to which they have bound.
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The peak activity will be around 40oC. The activity will fall sharply above 40oC. Apparatus 0.5 % starch buffered to pH 6.7 1% NaCl solution Fearons reagent 20% NaOH solution pH 6.7 buffer Amylase solution Distilled water Tongs Boiling tubes Boiling tube rack 100 cm3 measuring cylinder 1, 5 and 10 cm3 pipettes and safety pumps Gloves Goggles Cuvettes Stop clock Colorimeter Ice Bath (0 oC), Water baths Bunsen burner Tripod Gauze Heatproof Mat Safety * Lab coat (protect clothes) * Safety goggles (protective eye care) * Rubber gloves (protect hands. 20% NaOH is a corrosive irritant)
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The nails will grow when the top layer of cells are transformed into nail cells by keratinisation. The cells within the matrix will be divided up, the upper ones will become thickened and toughened through the keratinisation process. As more cells are produced the old ones are pushed outwards and flattened, they then become transparent and form part of the nail plate. The matrix also determines the shape and thickness of a nail so the longer the matrix is the thicker the nail will be. If however the matrix is damaged it can result in temporary loss of the nail or permanent damage to the nail plate.
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An increase in cAMP concentration, without glucose, is not sufficient to stimulate insulin secretion. Glucose therefore leads to an increased intracellular concentration of cAMP that is in turn thought to promote insulin secretion by depolarising the cell, that is, by making the resting potential become more positive. IF 15mM of glucose is added to a beta-cell within an isolated Islet of Langerhans, within about a minute its membrane potential is found to change from its resting potential of about -60mV to -30mV. This depolarization is a consequence of the decrease in the membrane's permeability to potassium ions that is observed in the presence of glucose.
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The theory behind this experiment is that of rate laws and rate expressions. Arsenious acid, the reducing agent present in this experiment, reacts with iodine at the rate it is formed.
however the most frequently type of rate law for this reaction is of the form; d [IO3-] =k([IO3-] m,[I-]n,[H+}p,.) dt (Equation 3) where m, n, p,... are determined by experiment, and each exponent in the equation is the order of the reaction with respect to the corresponding species, and the algebraic sum of the exponents is the overall order of the reaction. The equation for the reaction of arsenious acid and I3- : H3AsO3 + I3- + H2O?H AsO42- + 3I- +4H+ (Equation 4) While the equation for the overall reaction, up to the time of the starch end point, can be written as: IO3- + 3H3AsO3 ?
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Let us keep these two notes in mind (one, rejection of Cartesian vocabulary, and two, scientific world-view) as we consider the two theses put forth by BN. According to Searle, the two theses of BN work within a micro-macro schema that is compatible with the current scientific world-view. Using the micro-macro model, we can formulate the theses (combined) in another way by saying that minds and mental states are the higher-level phenomenon of the lower-level phenomenon that is physical brain processes.
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An antigen is anything which having invaded a host, causes the host to generate an immune response against itself. In this case the virus causing smallpox in humans and cowpox in cows.
It is these biochemical clusters which trigger the immune response. Immunological memory is the term used to describe how the adaptive immune system appears to remember all pathogens it has encountered previously, and changes behaviour as a consequence of earlier experience. It relates only to epitopes that have been encountered previously. Small lymphocytes are T and B cells found circulating in the blood and lymphatic system and stationary in the lymph nodes, spleen and other lymphoid organs. Each has receptor molecules on its surface with a unique structure and specificity that binds to just one epitope shape.
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Looking at the general population, the fingerprint ridge patterns tend to be: arch, 5.0%; radial loop 5.4%; ulnar loop, 63.5%; and whorl, 26.1%. (Also see, (Bio molecules, cells and genetics, unit handbook: 61BL0020), Polygenic traits: fingerprint ridge count Page: 20-22). Materials and Procedure (See, (Bio molecules, cells and genetics, unit handbook: 61BL0020), Polygenic traits: fingerprint ridge count Page: 22-23). Results Table of class results No. Of students Loops Whorls Arches Total Ridge count Gender Radial Ulnar (TRC) (M/F) 1 1 6 6 0 185 M 2 3 3 3 0 138 F 3 4 0 0 6 18 M 4
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AS Chemistry - CourseworkOpen Book Paper 1. There are two types of rubbers, natural and synthetic rubber. Natural rubber is predominantly
Below is the reaction of a synthetic rubber being polymerised. H H H H H2C CH2 CH2 H2C Butadiene Poly(cis-1,3-butadiene) There are many similarities between natural and synthetic rubber. Firstly it is evident that both contain cis molecules 2 .Discuss how the structures of natural and vulcanised rubber determine their properties and describe how vulcanising rubber leads to an improvement in its properties for use in car tires 3.Natural rubber has a thermoplastic nature and consequently it is not suitable for being used independently to construct a tyre. Therefore it is necessary that a tyre must be have specific chemicals and synthetic fibres added in order to improve the suitability of rubber being used as car tyres.
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Should we think of Fleming as a hero? IntroductionPenicillin has been such an important discovery because it has saved so many lives
dish flew in through the open window, when Fleming found the dish with the penicillin mould in it he was showing someone the work he had been doing recently and it was in the sink ready for him to wash it up. When Fleming found the dish he noticed that there was no germs growing around the structure of the mould, Fleming's individual skill was very important in the observation of the mould because he managed to notice that there were no germs when he was just skimming through his work showing it to one of his friends, when he managed to notice that there were no germs near the mould.
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Then you should describe the experiment you would do to test your hypothesis. Be sure to include controls, and describe the variables that would remain constant and the one that you want to test. (Remember, you can only test one variable at a time.) Include the type of data you would collect. The next section would be your expected results. Then you need to state what your conclusion would be depending on those results. Finally, do you accept or reject your hypothesis? Introduction: During summer last year, I had a rash, more like pimples only on my right cheek.
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With reference to membrane proteins, discuss the important role of water in defining the shape and function of biomolecules.
Due to the polar nature and the ability to form hydrogen bond make water a very versatile solvent. This is very important role of waters in biomolecules since most of the chemical reactions that occur in organism require material dissolved in water. The high H-bonding capacity allow it to act a non-electrolytes and dissolve polar compound such as glucose in the body. Water can also act as electrolytes due to the high capacity of hydration shells and high dielectric constant. This allows inorganic ionic material such as NaCl to become hydrated and dissolve in water. It can also act as polyelectrolytes where particles are in a colloidal suspension by hydrated surface ionic charge and an example of this is globular proteins.
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* 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.
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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).
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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.
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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.
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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.
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& 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
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