Studying the Effect of Salt on Cress Germination

PLANNING Initial Method . Prepare 8 sterile Petri dishes with a perfectly fitting circle of cotton wool and filter paper, this will sit on top of the wool 2. A control dish must also be set up using the same steps as above 3. Weigh out 8 different salt measures, at 0.25, 0.5, 0.75, 1, 1.25, 1.5 and 1.75 4. Measure out 8, 50ml beakers of distilled water 5. Add the one measure of salt into a beaker (1 beaker for each weight) and stir until the salt is dissolved and cannot be seen 6. Add one drop of Plant nutrient growth (e.g. baby bio) to each solution 7. Add each solution into individual Petri dishes which were made up earlier on, make sure the cotton wool and filter paper are allowed a small amount of time to absorb as much water as possible before the next step 8. Add 10 Cress seeds to each of the 8 solutions and place the lid on the dish 9. Place the dishes in are area which is well lit by natural light 0. Check the dishes each day for a week and top up each dish with the same solution if it is becoming dry, add the same amount to each dish (record what you add) 1. Count and record the percentage I chose to carry out my method in this fashion as it gave me the best way to see which salt concentration had the biggest effect. I chose 8 solutions as it gives me a good range to monitor the salinity effects. The solutions are based on findings in earlier research

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Find the relationship between amount of fat and amount of energy produced in different foods.

July 2001 Biology Coursework Year 10 Aim Find the relationship between amount of fat and amount of energy produced in different foods. Planning I am going to ignite different foods and see how much heat energy they give out. The food that causes the biggest amount of change in temperature will have the most amount of energy. However, calculations have to be carried out to create an average energy output per gram. Variables Independent Variables: This will change from food to food, thus giving me a range of different results. In this experiment it will be type of food. Dependant Variable: This is the amount of Energy per gram which can be calculated Controlled Variables: These are the things that will keep the same, in order to sustain a fair test. These are; * Apparatus * Type of boiling tube * Distance of boiling tube from Bunsen burner * Distance of food from boiling tube * Amount of time taken to move ignited food to boiling tube Fair Test It is essential that I keep it a fair test in order to sustain accurate results for comparison at the end. To ensure a fair test, I must keep the controlled variables for every test I do. The apparatus must all be kept the same because there may be some minor differences in insulation properties, or measure of accuracy between them. If this were to happen, it would prevent me from sustaining accurate results. The same

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The Effectiveness of Different Solutions to Prevent or Treat Malaria

Issue Report: The Effectiveness of Different Solutions to Prevent or Treat Malaria Malaria is a mosquito-borne infectious disease commonly known in tropical and subtropical regions such as Sub Saharan, Africa, Asia and America. It is a potentially fatal blood disease caused by protozoan parasites of the genus Plasmodium. There are four types of plasmodium parasite that can infect humans and these are: Plasmodium falciparum and Plasmodium vivax, Plasmodium ovale and Plasmodium malariaecan. Malaria parasites are transmitted successively infecting two types of hosts: Female Anopheles mosquitos and humans. This is how the Malaria Life Cycle works: Bitten by a mosquito, during feeding, malaria parasites (sporozoites) leave the mosquito salivary gland and enter the human bloodstream. Then the malaria parasites enter the liver, infect the liver cells (hepatocytes) where they multiply into merozoites parasites. The liver cells eventually rupture and release more parasites in the blood. The parasites invade the red blood cells where they continue to multiply and develop to trophozoites and schizonts and rupture the cells. The blood stages cause the clinical symptoms of malaria. Some parasites enter the red blood cells and develop into male and female reproductive cells (termed gametocytes). The gametocytes are transferred to another mosquito when it feeds on the human. Then the

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Experiment examining the effect of mineral deficiencies on plant growth.

Core Practical Write Up Investigate the effect of plant mineral deficiencies Planning Dependant variable: we are going to be observing the changes in root length, plant body length, number of living leaves and colours of leaves. Independent variable: we will be varying the mineral deficiency in the agar jellies. There will be five ager jelly dishes. There will be one dish containing all nutrients; one dish lacking magnesium; one dish lacking nitrogen; one dish lacking calcium; and one without any of those nutrients. Controlled variables: We are going to be controlling the type of plant growing in the agar jelly. We are using Mexican hat plantlets for our experiment. The time between each measurement is going to be controlled, when one plant is observed all the other plants will also be observed so plants have equal amounts of time to grow. Hypothesis: From what I have learnt in class when a plant lacks nitrogen it should be unable to grow larger because amino acids production will be reduced. A plant lacking magnesium would be unable to produce chlorophyll therefore the leaves would become yellow coloured and not so green. The plant lacking calcium would have a stunted growth due to the role of calcium ions in the structure of the cell walls and membrane permeability. I expect the plant lacking all nutrients to have all three of these properties and possibly just die

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Biology coursework investigation: Comparing the length of ivy leaves (Hedera helix) in areas of greater illumination and shade

Biology coursework investigation: "Comparing the length of ivy leaves (Hedera helix) in areas of greater illumination and shade" Abstract The aim of this study was to compare the length of leaves of ivy plants (Hedera helix) climbing on two Hornbeam trees (Carpinus betulus) in two different light intensities. The hypothesis was that the lengths of Hedera helix exposed to a higher light intensity ("sun leaves") would be shorter than Hedera helix exposed to a lower intensity of light ("shade leaves"). The light intensity was measured using a light meter and the lengths of the midrib vein of 30 leaves were measured from each of the two trees. The method describes how leaves were chosen to ensure that they were approximately the same age. The results were analysed using a students t statistical test and it was concluded that there was a significant difference between the lengths of the two groups of leaves. The main reason for this was concluded to be the structural differences in the Hedera helix in the sun and shade. Background information on Hedera helix Previous investigations have shown that there are structural differences between the leaves of ivy in areas of high light intensity and areas of low light intensity. Shade leaves of ivy are typically thinner than sun leaves and also have a larger area in comparison. This is due to them having a thinner cuticle and one layer

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Purpose: To investigate the effect of caffeine on the heart rate of Daphnia (water fleas).

Does caffeine affect heart rate? Purpose: To investigate the effect of caffeine on the heart rate of Daphnia (water fleas). INTRODUCTION: Caffeine is a drug that is naturally produced in the leaves and seeds of many plants. It is also produced artificially and added to certain foods. These days, caffeine is also used as flavour enhancer in wide range of cola and other soft drinks. In addition, it has medicinal use in aspirin preparations and is found in weight-loss drugs and as a stimulant in Red Bull. In humans, caffeine acts a stimulant drug, causing increased amount of stimulatory neurotransmitters to be relaxed. At high levels of caffeine consumption can lead to restlessness, insomnia and anxiety, causing raised stress level and high blood pressure. This can lead to heart and circulatory problems. Safety: . Handle glassware with care. 2. Wear a lab coat to prevent spill on fabrics. 3. The microscope is fragile and the light bulbs can get hot so handle with care. Apparatus: . Culture of Daphnia (water fleas) 2. Cavity slides 3. Dropping pipettes 4. Distilled water 5. Cotton wool 6. Standard glassware (beakers, measuring cylinders, etc.) 7. Stopwatch 8. Filter paper 9. Microscope Hypotheses: I believe that the Daphnia subjected to caffeine solution will show a rise in heart rate, this rise in heart rate will depend on the concentration of

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Ethics behind selective breeding of animals

Ethics behind selective breeding of animals Selective breeding, also known as artificial selection involves identifying individuals with the desired characteristics and using them to parent the next generation. Ethical concerns and benefits of selective breeding Alongside the potential benefits, selective breeding of animals raises a variety of ethical concerns. There are two main concerns. These are: Fundamental moral objections against doing something "unnatural" or, specifically to their artificial selection, for example concerns about the consequences of reduced genetic diversity. As stated above some believe that selective breeding interferes with nature. Selective breeding has produced livestock that gives greater yields. This has given rise to a reliable cheap food source throughout the year. It could considerably raise the standard of living in developing countries where starvation is a prevalent problem. However some believe the development of new varieties should be allowed to take place naturally. We should accept a lower standard of living in return for natural breeding. When looking at this problem we should look at how useful the varieties will be in terms of helping humans. Perhaps one way forward would be to allow selective breeding only in countries where it is most needed. Many people however would take the attitude that human wellbeing is more

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'An investigation into the ability of two strains of the yeast Saccharomyces cerevisiae to utilise different carbon sources as substrates for cellular respiration'.

'An investigation into the ability of two strains of the yeast Saccharomyces cerevisiae to utilise different carbon sources as substrates for cellular respiration' Introduction The purpose of this investigation is to compare the ability of two different strains of yeast to respire, when using different sugars as respiration substrates. Considering the lengths that have been reached to develop varieties of yeast with greater suitability and effectiveness for very particular fermentation purposes, it seems reasonable to suppose that two different strains of the same species of yeast, selected for their different fermentation properties, have developed requirements that are not uniform. As a result of the selection and development process, yeast best suited to ferment in a given application, possess a range of different characteristics. One such characteristic may be the ability to metabolise different carbon sources at different rates. This quality is important because in each application where different respiration substrates are available, a specific strain of yeast may be required. Yeast unable to utilise the available carbon sources will have undesirable fermentation rates, and therefore may not be selected for use in that application. The two yeast here compared, have two such different applications. The first yeast from the Saccharomyces cerevisiae variety is of the

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A comparative study of the density of patella vulgata (common limpet) across a sheltered shore and an exposed shore.

A comparative study of the density of patella vulgata (common limpet) across a sheltered shore and an exposed shore Aim: - To investigate the limpet density of patella vulgaris (common limpet) across a sheltered rock shore and an exposed rocky shore at the optimum niche level at both shores. Introduction: - Limpets are distinctive animals that are best known for their ability to cling onto rocks. Patella vulgata (common limpet) can be found wherever there is a rock layer firm enough for it to attach to the rocks or stones, this can be from the high shore down to the lowest part of the tide. It is abundant on all rocky shores of all wave exposure. The limpet is usually not abundant on shores where there are large growths of seaweed. The conical shell of Patella vulgata is up to 6 cm long with radiating ridges and the top central or slightly forward. Individuals from the high shore generally have a taller shell and smaller shell length when compared to juveniles and low shore animals. The outer surface of the shell is greyish white, sometimes with a yellow tint, and has crude radiating ridges and well-marked growth lines. The inner surface is smooth and greenish-grey in colour. The sole of the foot is yellowish, dull orange or brown with a grey or greenish tinge. The mantle skirt is fringed with transparent tentacles arranged in three series of different lengths,

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How is ATP produced and used in living organisms?

How is ATP produced and used in living organisms? ATP (adenosine triphosphate) is required in all living cells as a continual supply of energy, to be used in processes, which keep the organism alive such as muscle contraction. ATP is made up of three main components, the base (adenine), a phosphate chain (made of three phosphate groups) and a ribose sugar backbone. The energy released from the respiration of Glucose is used to add inorganic phosphate groups to ADP to form ATP. Below is a diagram of ATP. The first step in the production of ATP and the store of energy is Glycolysis, which occurs in both aerobic and anaerobic respiration. In both cases Glycolysis takes place in the cytoplasm of the cell, because glucose is too big to get in to the mitochondria. The process starts with glucose (a six carbon sugar) and two ATP molecules needed to start off the process, (as sugars aren't very reactive) the glucose is transferred to another 6 Carbon Sugar (Fructose Bisphoshate). This breaks it down into two 3Carbon Sugars called Pyruvates. Two ATP molecules per Pyruvate is produced through the condensation reaction of a phosphate group called phosphorylation and ADP (adenosine diphosphate) forming ATP. The excess hydrogen ions are removed by the aid of NAD to form one molecule of reduced NAD per pyruvate. If the organism is anaerobic or when the supply of oxygen is not enough

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