An investigation into the inhibiting effect of tomato juice on the germination of cress seeds.
An investigation into the inhibiting effect of tomato juice on the germination of cress seeds Introduction I intend to analyse the inhibiting effect of tomato juice on the germination of tomato juice. In this introduction I will answer important questions such as; what are inhibitors? How might inhibitors affect germination? , etc. When answering the questions, I will be considering different areas of the syllabus (e.g. genetics, inter-specific competition, enzymes and inhibitors, practical skills, etc.) This will help me appreciate the theory behind the investigation and hence help me formulate an effective plan and method. Inhibitors are chemicals, which inhibit the action of an enzyme. There are two main types of inhibitors: reversible and non-reversible. Non-reversible inhibitors permanently damage enzymes. They attach themselves to the enzyme molecule and cause important bonds to break, causing irreparable damage. This denatures the enzyme and does not allow it to function. Diagram showing non-reversible inhibition: Normal arrangement Change caused by non-reversible inhibitor Reversible inhibitors inhibit the action of enzymes but do not do permanent damage. Once the reversible inhibitor is removed; the enzyme will return to normal. Reversible inhibitors can be divided into two types:
The Effect Of Temperature on the Respiration Of Yeast.
The Effect Of Temperature on the Respiration Of Yeast Introduction: - I am going to find out how temperature effects the respitory action of yeast. I am going to do this by using six different temperatures, 25oC, 30oC, 35oC, 40oC, 45oC and 50oC and a solution called TTC which is absorbed by the yeast cells turning them pink when hydrogen is removed from the metabolic pathway by the dehydrogenase enzyme. Background Information: - Yeast: - Yeast is unicellular fungus that buds profusely under favourable conditions. They are classified as sac-fungi (Ascomyctes) even though they are unicellular. Yeast is common in areas where there is sugar because of this they are given the name saccharomyces (Sugar fungi). They grow on the surface of fruits, in the nectar of flowers, in sap excluded from trees, in the soil and in fresh water. Yeasts are used in all sorts of arrears such as alcoholic fermentation (fermentation is the name given only to the anaerobic respiration of yeast) to baking bread. Yeasts are of a great economic importance and are yeast for biochemical research for example in respiration and enzymes. Yeast exists as Diploid or Haploid cells and divides by mitosis and meiosis. Yeasts are not plant or animal because they do not photosynthesise and they do not have any chloroplast. Yeast is a saprophyte. This is an organism, which obtains its nutrients from dead or
'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
Enzymes - investigate how the substrate concentration (H2O2) affects the activity of catalase on hydrogen peroxide.
Enzymes Aim To investigate how the substrate concentration (H2O2) affects the activity of catalase on hydrogen peroxide. Introduction Enzymes are protein molecules, which can be defined as biological catalysts. A catalyst is a molecule that speeds up a chemical reaction, but remains unchanged at the end of the reaction. An enzyme catalyses virtually every metabolic reaction, which takes place within a living organism. Enzymes have a globular protein structure. The enzyme molecules are coiled into a precise three-dimensional shape, with hydrophillic R groups (side chains) on the outside of the molecule ensuring that they are soluble. Enzyme molecules also have an active site, which is usually a cleft of depression, to which another molecule or molecules can bind. This molecule is the substrate of the enzyme. The shape of the active site allows the substrate to fit perfectly, and to be held in place by temporary bonds, which form between the substrate and some of the R groups of the enzyme's amino acids. The combined structure is termed the enzyme-substrate complex. Each type of enzyme will usually act on only one type of substrate molecule. This is because the shape of the active site will only allow one shape of molecule to fit. The enzyme is said to be specific for this substrate. The enzyme may catalyse one of two types of reactions. One in which the substrate
Osmosis. Aim: To find the molarity of potato tubers cell sap. BIOLOGICAL KNOWLEDGE
TABLE OF CONTENTS Biological Knowledge ... 3 Explanation ... 3 Types of solutions and its effects on plant cell ... 4 Factors affecting rates of osmosis ... 6 Outline Method ... 9 Apparatus ... 9 Materials ... 9 Risk Assessments ... 9 Precautions ... 9 Apparatus Diagrams ... 10 Factors to be controlled ... 11 Method ... 11 Calculations to be used ... 12 Predicted Results ... 12 Prior Test ... 13 Obtaining Evidence ... 16 Apparatus ... 16 Materials ... 16 Risk Assessments ... 16 Precautions ... 16 Method ... 17 Results obtained for Mass ... 18 Results obtained for Length ... 19 Analysis ... 21 Trends in the Bar charts ... 25 Scientific Explanation ... 25 Determination of molarity ... 28 How far I have reached my predicted results ... 30 Evaluation ... 32 Errors ... 32 Accuracy and reliability of my results ... 32 Extension work ... 33 Bibliography ... 33 INTRODUCTION Biology Coursework Aim: To find the molarity of potato tuber's cell sap. BIOLOGICAL KNOWLEDGE Osmosis is the diffusion of fluid through a semi-permeable membrane from a solution with a low solute concentration to a solution with a higher solute
To what extent were Malcolm X and the subsequent Black Power Movement the 'Evil Twin' of the Civil Rights Movement in the late twentieth century in the United States of America?
To what extent were Malcolm X and the subsequent Black Power Movement the 'Evil Twin'1 of the Civil Rights Movement in the late twentieth century in the United States of America? Malcolm X2 and the subsequent Black Power3 Movement (BPM) stemmed from the nationalist African American population and so took a different stance in their fight for Civil Rights than other leaders such as Martin Luther King4 (King). With this distinction, has come a historical debate into whether Malcolm X and the BPM aided or hindered the Civil Rights Movement (CRM); something that has been debated between historians such as Sitkoff and Cook. The purpose of this study is to decide whether Malcolm X and the BPM are indeed the 'evil twin' of the CRM or whether this title is unjust. Malcolm X was a black nationalist5 and a member of the Nation of Islam6. Malcolm X, through his father, garnered the beliefs of Marcus Garvey7 and his 'Back to Africa' campaign. He also believed in militancy as a method to attain black independence through the notion; 'fight violence with violence'. He believed that rather than allowing the continual persecution of African Americans by whites, it was rational for African Americans to defend themselves with as much force as was necessary as advocated in his 'by any means necessary'8 speech. This caused much tension between the two distinct civil rights movements because it
Beetroot Practical Write up
Biology Coursework Beetroot Hypothesis: To investigate the effect of different concentrations of ethanol on the permeability of beetroot cell membranes. Prediction: By exposing a membrane to a solvent, ethanol, it will affect its permeability. Therefore higher the concentration of the solvent, the more permeable the membrane will be. But by increasing the concentrations of the ethanol beyond a certain point it may have no affect on the cell membrane because the ethanol would have broken down the cell membrane completely. This is because of the effect of ethanol on the lipids in the membrane. Also, more dye would be present as the lipids are essential to the structure of the cell membrane as they control the substances that enter and leave the cell. Ethanol could also destroy some the proteins or denature the structure because protein has a tertiary structure. The ethanol would destroy the hydrogen bonds that hold the protein structure. Therefore, with the lipids and proteins destroyed in the cell membrane, the pigment is allowed to escape from the cell due to there being no cell membrane holding substances in the cell. Scientific Knowledge: Transfer across cell membrane structure: There are many ways that ions and molecules are transported across the cell membrane. By this, the cell must acquire the ions and molecules they need from their surrounding
Investigating the forces acting on a trolley on a ramp
Physics coursework Investigating the forces acting on a trolley on a ramp Contents Page 3 -> Method Page 4 -> Theory Page 7 -> Results Page 9 -> Error Page 18 -> Appendixes Method The aim of the investigation was to investigate the forces acting on a trolley as it rolled down a ramp, and also to investigate the factors which may contribute to the results. To do this, a trolley and a ramp set at a variety of angles of incline were used, and then, using a light gate, the speed at which the trolley was moving when it passed through the light gate was calculated. The variables were the starting distance of the trolley in relation to the light gate and the angle of the ramp. Firstly, the equipment was set up as in fig. 1. The trolley was then run down the ramp with a piece of card attached to the side. This card was of a known length and could hence be used to calculate the velocity at which the trolley was moving. While the light gate did actually calculate the velocity, it only gave the answer to 2 decimal places, whereas it gave the time to 2 decimal places. Furthermore, the light gate calculated the velocity with the assumption that the card was exactly 100mm, whereas when the card was actually measured, this was a value closer to 102mm (±0.5mm). Next, after the trolley had passed through the light gate, the information from that 'run' appeared
Find out if enzymes work faster or slower at different temperatures.
Nick Spong Biology 10/11/03 Introduction This is the plan and evaluation of an experiment to find out if enzymes work faster or slower at different temperatures. We will be timing how long it takes to see a cross through 20cm3 of Marvel milk solution at three different temperatures. We will be using the enzyme neutrase to break down Marvel milk. Hypothesis My hypothesis (theory) is that at temperatures over 40°c the neutrase will be increasingly denatured and the milk will not clarify. Under 40°c the neutrase will be slowed down. However I predict that at 40°c the neutrase will be working well as this temperature is near its optimum temperature and so the milk will decolorize the fastest. I have made my prediction based on the following evidence: The reason that the milk will decolorize or do anything at all is because neutrase is an enzyme. Enzymes are biological catalysts. This means that they are a biological life form that catalyses (speeds up) a process. They have an optimum temperature and pH. Both of these have to be almost exactly right, otherwise their performance deteriorates rapidly. In high temperatures the enzyme will be denatured and will not work even if you bring the temperature back down. However, at low temperatures, and low and high pH's, all you have to do is bring the environment close to the enzyme's optimum environment and the enzyme
UNIT 1 COMMUNICATION P5, P6, M3 AND D1 , D2
Contents page Page 2 Introduction Page 3 Task 1 (D2) analysing communications between service users and key people Page 6 Task 2 (P5) participation in two interactions Page 8 Task 3 (P6) review of communications in the two interactions undertaken Page 10 Task 4 (M3) explanation of how communications could be more effective Page 12 Task 5 (D1) analysing the two interactions Page 14 Bibliographies Appendix The following assessment is about communications in the work placement. There are five pass criteria's to this assessment, which consists of two passes, one merit and two distinctions. The assessment focuses on how communication skills are used and their effectiveness. Task 1 (D2) Analyse how communication in health and social care settings assists patient/service users and other key people. The following observations were done in a 70-bed residential care/nursing home with a separate EMI unit, which caters for the mentally ill. There are two floors, each one a mirror image of the other. On each floor there are 35 bedrooms, 20 in the main part and 15 in the EMI unit. There is a resident's lounge on each floor that has a conservatory on the end where the residents who smoke can sit. In each lounge there is a central fireplace, a television at one end and a display cabinet at the other end, which has a music system on it. There are approximately 20 reclining chairs
