The comparison of antibacterial properties of herbal products and standard antibiotics
The comparison of antibacterial properties of herbal products and standard antibiotics Introduction: This is As biology coursework, studying the area of microbiology the main investigation contains the comparison of antibacterial properties of herbal products and standard antibiotics. Aim: The aim is to investigate the effect of herbal products against standard antibiotics on bacteria growth. To examine the extent to which the herbal products (tea tree oil and peppermint oil) and the standard antibiotics (penicillin and streptomycin), reduce bacteria growth of E.coli and M.luteus. This will be discovered by measuring the growth of bacteria on the agar plates and comparing the results. Background information: The proposed aim surrounds the study of bacteria growth and various other products, which can have an affect on the growth rate; it is therefore necessary to look deeper into the topic criteria to get a wider understanding and to help design an appropriate hypothesis. From self-knowledge antibiotics are chemicals produced by microorganisms, which are designed to inhibit and destroy specific pathogens when used at low temperatures. Antibiotics release chemicals, which inhibit bacterial growth and work on a specific action site. The first founded antibiotic was penicillin discovered accidentally by Alexander Fleming in 1928 from a mold culture. It can be
Waves and Cosmology - AQA GCE Physics Revision Notes
Matter waves * As waves can behave as a stream of particles, particles can also behave as a wave De Broglie wavelength: λ = where mv is the momentum of the particle * Diffraction rings are where electron waves interfere constructively to produce a maximum - energy gained by electron is equal to the kinetic energy of the electron. Here, electrons are accelerated by a voltage of 2000 V; 2000 x (1.6 x 10-19) = x (9.11 x 10-31) x v2 Mass of electron = 9.11 x 10-31 3.2 x 10-16 = x (9.11 x 10-31) x v2 v2 = 7.025247 x 1014 v = 2.65 x 107 ms-1 So the momentum of electron: (9.11 x 10-31) x (2.7 x 107) = 2.5 x 10-23 kgm/s The de Broglie wavelength: λ = = = 2.6 x 10-11 m * If the accelerating voltage increases, energy and momentum of the electron would decrease the wavelength. Shorter wavelength blue light falling on diffraction grating produced fringes that are closer together than longer wavelengths (red light). * Resolving power is the wavelength of radiation used to determine the smallest object we are able to detect with it. The smaller the wavelength, the better the resolution. I.e. Resolution of visible object is limited by its wavelength of 5 x 10-7 m. In electron microscope, electrons are accelerated through 30000 V have wavelength of about 10-12 m, and so can produce images of object as small as a nanometre. When
To make sure we have plenty of energy in the future, it's up to all of us to use energy wisely. We must all conserve energy and use it efficiently. It also ups to those of you who will want to create the new energy technologies of the future.
Fossil fuels enable human ingevnovnuity and gave rise to the Industrial Revolution. Coal-fired electricity empowers humankind's evolution in the Information Age. Humans harness earth's abundant fossil fuels resource - formed from the remains of prehistoric plant and animal life - as our primary source of energy. In a very real sense, using fossil fuels recycles the product of solar energy locked-up during photosynthesis over millions and millions of years. Whether using coal to make most of the world's electricity, petroleum as the lifeblood of transportation or, along with natural gas, as a feedstock for myriad industrial and commercial uses, fossil fuels are keys to our industrial evolution. Where Fossil Fuels Come From There are three major forms of fossil fuels: coal, oil and natural gas. All three were formed many millions of years ago during the time of the dinosaurs -- hence the name fossil fuels. Fossil fuels are made up of decomposed plant and animal matter. Plants change energy they receive from the sun into stored energy. This energy is food used by the plant. This is called photosynthesis. Animals eat plants to make energy. And people eat animals and plants to get energy to do work. When plants and dinosaurs and other ancient creatures died, they decomposed and became buried, layer upon layer under the ground. It took millions of years to form these
GENETIC ENGEERING
GENETIC ENGEERING GENETIC ENGEERING Genetic engineering, also known as recombinant DNA technology, means altering the genes in a living organism to produce a Genetically Modified Organism (GMO) with a new genotype. Various kinds of genetic modification are possible: inserting a foreign gene from one species into another, forming a transgenic organism; altering an existing gene so that its product is changed; or changing gene expression so that it is translated more often or not at all. TECHNIGUES OF GENETIC ENGEERING Genetic engineering is a very young discipline, and is only possible due to the development of techniques from the 1960s onwards. These techniques have been made possible from our greater understanding of DNA and how it functions following the discovery of its structure by Watson and Crick in 1953. Although the final goal of genetic engineering is usually the expression of a gene in a host, in fact most of the techniques and time in genetic engineering are spent isolating a gene and then cloning it. This table lists the techniques that we'll look at in detail. TECHNIQUE PURPOSE Restriction Enzymes To cut DNA at specific points, making small fragments DNA Ligase To join DNA fragments together Vectors To carry DNA into cells and ensure replication Plasmids Common kind of vector Genetic Markers To identify cells that have been transformed PCR To
Management style, culture & organizational structure.
GENETIC ENGEERING GENETIC ENGEERING Genetic engineering, also known as recombinant DNA technology, means altering the genes in a living organism to produce a Genetically Modified Organism (GMO) with a new genotype. Various kinds of genetic modification are possible: inserting a foreign gene from one species into another, forming a transgenic organism; altering an existing gene so that its product is changed; or changing gene expression so that it is translated more often or not at all. TECHNIGUES OF GENETIC ENGEERING Genetic engineering is a very young discipline, and is only possible due to the development of techniques from the 1960s onwards. These techniques have been made possible from our greater understanding of DNA and how it functions following the discovery of its structure by Watson and Crick in 1953. Although the final goal of genetic engineering is usually the expression of a gene in a host, in fact most of the techniques and time in genetic engineering are spent isolating a gene and then cloning it. This table lists the techniques that we'll look at in detail. TECHNIQUE PURPOSE Restriction Enzymes To cut DNA at specific points, making small fragments DNA Ligase To join DNA fragments together Vectors To carry DNA into cells and ensure replication Plasmids Common kind of vector Genetic Markers To identify cells that have been transformed PCR To
Genetic Modification
In a comment to the press that the EU Commission gave out together with the report this week they claimed that "there is nothing secret about the study referred to in the Greenpeace press release. The version published on their [the Greenpeace] web-site is a draft ..." However, this is simply not true. The letters that accompanied the study when it was delivered to the European Commission in January, and that were obtained by Greenpeace, clearly state that the study was presented in its "final version" at that time. The study states that farmers who don't want to cultivate GMOs would face high additional, in some cases unsustainable, costs of production if genetically engineered (GE) crops were commercially grown on a large scale in Europe. The study predicts that the situation would become particularly critical for organic farming of oilseed rape as well as for intensive production of conventional maize. Seed and crop purity from GE pollution, at a detection level of 0.1 percent, would be virtually impossible in most cases. This effectively means that all products and seeds of oilseed rape and maize would be contaminated with GE crops to a certain extent. Organic farming exempt of GMOs, as we know it today and as it is defined in the EU Regulations, will be doomed. These findings confirm the need for "zero tolerance" for seed contamination, the standard demanded by
Find the enthalpy change of combustion of a number of alcohol's' so that you can investigate how and why the enthalpy change is affected by the molecular structure of the alcohol.
Aim The aim is to find the enthalpy change of combustion of a number of alcohol's' so that you can investigate how and why the enthalpy change is affected by the molecular structure of the alcohol. Background Knowledge Combustion is principally the oxidation of carbon compounds by oxygen in air to form CO2 if there is a sufficient amount of oxygen. The hydrogen in a compound forms H2O. Combustion produces heat as well as carbon dioxide and water. The enthalpy change of combustion is the enthalpy change that occurs when 1 mole of a fuel is burned completely in oxygen. I can use an enthalpy cycle to work the combustion value out only if you have the right information. The energy contained in the bonds of the products is less than the energy contained in the bonds of the reactants. The difference in energy is released as heat. Energy releasing reactions are called exothermic reactions. Calorimetery is a way to determine the amount of heat produced in a reaction. Calorimeters are devices to measure heat released by a reaction. The temperature of the calorimeter increases as heat is released by the reaction. For any reaction to take place bonds must be broken and made Bond breaking requires energy whilst bond making releases energy. Bonds between different atoms require or release different amounts of energy when broken or made because they are different in
"An investigation into the Respiration of Carbohydrate Substrates by Yeast."
AS Biology Coursework 2004. Lucy Nuttney "An investigation into the Respiration of Carbohydrate Substrates by Yeast." Abstract. The investigation considered the reactivity of respiration of three different carbohydrate substrates; glucose, sucrose and starch, by two different sub-species of saccharomyces cerevisiae yeast. The rate of reaction was measured by collecting volumes of gas in a displacement reaction at standardised conditions e.g. time, temperature, pressure, volume of yeast/ sugar. Results showed that glucose produced the most carbon dioxide, followed by sucrose then starch, the biggest difference being between sucrose and starch. Baker's yeast had a slightly higher average than brewer's yeast but it was not considered to be a significant difference and therefore could have been due to chance. It was concluded that both yeasts respire glucose and sucrose at insignificantly different rates but the difference between starch is much larger and therefore much more significant. Pilot Experiment. Before we could test which carbohydrate and type of yeast produced more carbon dioxide, we had to standardise the other variables of this experiment; temperature and concentration. Therefore, in order to find the optimum conditions we carried out a pilot experiment. In this experiment we used a range of temperatures from 10° to 60°C and
An experiment to investigate the effect of enzyme concentration on the rate of milk lipid digestion by lipase.
Adam Hussein 6B1 28-12-02 An experiment to investigate the effect of enzyme concentration on the rate of milk lipid digestion by lipase. Biology Coursework Plan: Aim: This investigation aims to find out how enzyme concentration affects the rate of milk fat digestion by lipase enzyme. As a result of the experiment I aim to have quantitative results which I can then use to plot graphs illustrating the effect of lipase. Prediction: I predict that as the concentration of lipase enzyme increases, so to will the rate of reaction. The two will be directly proportional to each other up to the point where the substrate (milk fat) becomes rate limiting. This is the point where there are so many enzyme molecules and not enough substrate molecules for them to catalyse. The rate will therefore remain the same past this point as shown in the below graph. Variables: These are factors that will affect the reaction in some way. In order for the experiment to be successful in supplying reliably accurate results all variables must be kept constant apart from the enzyme concentration will be varied by known amounts to show the effect it has on the rate of lipid digestion by lipase. Below are the variables and explanations on how they will be kept constant in order to keep this experiment a fair test, and what affect them not being kept constant will have on the results. - Bile
chemistry of renewable resources
Introduction Everything we need - our resources have come from our planet, whether it is food, water, metals or fuels. It is known that if we use up any one of the earths resources then we will be without it forever. In this report I will look at some general principles of how non-renewable and renewable resources are used and the effect this can have on our environment. The resources that are most important to us are coal, metals, oil, gas, petrol and limestone. Without these we will be helpless. Also, these can only be replaced by nature after many million years. We call these non-renewable resources. Many industries rely on these as source of raw materials and will face problems unless new sources or new manufacturing techniques are found. We cannot find any techniques because most of the earths materials are so mixed up, that we can't sort them out and make them useful. On the other hand renewable resources renew themselves more quickly such as plants grown for food, and fuel. But these can be used up too fast if we do not use them carefully. These resources are in continuous supply, for instance wind and solar energy. Scientists are working very hard on developing new ways to use these renewable resources. But first industry needs to make more products that use the safe environmentally energy like solar powered vehicles. In the future they could also include the use of
