Investigation on how pH affects free and immobilised catalase enzymes.
Investigation on how pH affects free and immobilised catalase enzymes Hypothesis I hypothesis that as the ph of the solution that my enzymes are in (immobilised or free) moves away from neutral to more acidic or alkaline solutions that the amount of oxygen produced from the break down of hydrogen peroxide decreases. This can be explained by the research in which I stated how in acidic conditions enzymes are H+ acceptors and H+ donators in alkaline solutions this then breaks and destabilizes the ionic bonds denaturing the enzyme as it becomes unravelled. Also in my research I stated how the H+ ions would alter the globular shape of the protein distorting the active site. This distortion would affect the reaction rate as it would slow down due to the active site being distorted so it takes longer to break down the hydrogen peroxide and because more and more of the enzymes become distorted by the excess H+ or OH- ions meaning less active sites that are available to carry out the reaction. This can be proved by my preliminary test results, in which is showed when the ph was 13 or 2 the amount of oxygen produced was significantly reduced. I finally hypothesis that the immobilised enzymes have a higher tolerance to ph this is due also to my research which showed that when immobilised enzymes were more tolerant to heat and so I can theorise that it may also be the same for changes
Investigation on Osmosis.
Carly Mckenzie 19TH April 2002 Investigation on Osmosis Aim We are trying to discover how changing a certain variable would affect the rate of osmosis of skinless potatoes. Variables There are several factors which affect the rate of osmosis such as the potato (in this case) must not have any peel on it as the peel of a potato is impermeable and therefore would prevent the movement of the water. Here are the possible variables (listed below): - * The width and length give different surface areas which change the amount of osmosis performed by the plant (bigger surface area = more osmosis and vice versa) * Different vegetables have different concentrations of solution inside * Temperature-high temperatures give a faster rate of osmosis * The volume of the solution-the potato must be entirely covered for complete osmosis * Light intensity-strong light gives heat. (Heat as said above) * The type of solution e.g. sugar solution * Must use the same potato as different potatoes may have different concentrations inside * Must have a bung to prevent evaporation of the solution We are changing the concentration of the solution. We are going to be changing it to 0.0M, 0.2M, 0.4M, 0.6M and 0.8M. Prediction Osmosis is the movement of water from a dilute solution (lots of H20) to a concentrated solution (little H20) through a semi-permeable membrane. The experiment we
Investigation into Osmosis.
Investigation into Osmosis Aim To find the concentration of salt solution that is the same as the concentration of dissolved substances in potato tissue. At this point osmosis will not occur Prediction From my preliminary work I can determine that the concentration will be between 0 and 1.0m (Molars). In the preliminary work the potatoes gained 7% mass at 0m and lost 16.1% at 1.0m Apparatus Film Canisters Salt Solutions of Concentrations 0m, 0.25m, 0.5M, .075m and 1m 200cm³ measuring cylinder Potato Cork Borer Ruler Scalpel Balance Method . Use the measuring cylinder to measure 20cm³ of each solution into film canisters. Label the canisters 2. Use the cork borer to make potato cylinders and cut them into 2 pieces each 2cm in length 3. Record the start measurement in the table of results 4. Put 2 potato pieces into each film canister 5. Leave for 10 minutes 6. Take each potato piece out of the solution and shake it 3 times to remove excess liquid 7. Re-measure each potato piece and record the results in the table 8. Complete the table Fair test In the experiment the only variables should be molarity of solution and the different weights of the potato cylinders. To keep the experiment fair I will keep the following the things the same throughout : Keep the potato cylinders the same length (2cm). If a cylinder was longer than the other than osmosis will
Investigation into Osmosis.
Investigation into Osmosis in Potato Cylinders. Planning I am investigating the effect of osmosis on a potato. Osmosis is the diffusion of water down a concentration gradient through a semi permeable membrane. I am investigating the effect of water concentration on the potato cylinders. This means that I will put potato cylinders into salt solutions of different concentrations. Factors - Size of cylinder - Volume of solution potato is in - Time left in solution - Surface area of potato cylinder If I am going to make this a fair test, then I will have to control these other factors. The size of the potato is very important. This is because if the size of the potato varies, so will the amount of mass it can loose or gain. I am going to try to cut all the pieces of potatoes, to the same size. To ensure this I will use a cork borer. I will have cylinders with the same width and height, but the length of the cylinders will differ. I am going to cut the cylinders to 3cm in length. The light intensity cannot really me measured or kept the same, as the cylinders will be moved from one room to another, for storage. However I will try to keep the cylinders in the same place when I am storing them. The mass of the potato is a variable, and this means that it will be measured throughout the experiment. I will measure the mass in grams. The potato cylinder will be
Investigating the enzyme Catalase
Investigating the enzyme Catalase-AS biology coursework Introduction The experiment being carried out will find the effects of the enzyme catalase with different concentrations of substrate. . This enzyme is common in living organisms and its function is to catalyze the decomposition of hydrogen peroxide to water and oxygen. Hydrogen peroxide is a poisonous by product of metabolism, it can kill cells. Catalase from a potato will be used. An enzyme is a protein produced by any living organism which acts as a catalyst in specific reactions without being used up. All cells produce H2O2 2H2O2 › 2H2O + O2 in Metabolism. It is toxic so it is broken down by catalase. The factors that affect the enzymes are: Temperature changes - catalase works well at high temperatures up to 45°C. This is because they gain kinetic energy so the move around faster, more substrates can be broken down in the same amount of time. After then however the enzymes start to denature. At a low temperature the enzymes do not have as much kinetic energy so they don't work as fast. If its higher than 45°C, then the loses its tertiary structure as the bonds holding it together are broken so the enzyme loses its active site shape. pH changes - There is a narrow range of pH's that the catalase can work in. It works well at pH 7. If the pH goes above or below this, there will be a change in the
Potato and Osmosis Investigation
Potato and Osmosis Investigation Planning Aim: To investigate the effect of varying concentration of a certain sugar solution on the rate of osmosis between the solution and a potato chip of a given size. Hypothesis: Osmosis is defined as the movement of water or any other solutions molecules from a region in which they are highly concentrated to a region in which they are less concentrated. This movement must take place across a partially permeable membrane such as a cell wall, which lets smaller molecules such as water through but does not allow bigger molecules to pass through. The molecules will continue to diffuse until the area in which the molecules are found reaches a state of equilibrium, meaning that the molecules are randomly distributed throughout an object, with no area having a higher or lower concentration than any other. For this particular investigation I think that the lower the concentration of the sugar solution in the test tube the larger the mass of the potato will be. This is because the water molecules pass from a high concentration, i.e. In the water itself, to a low concentration, i.e. In the potato chip. Therefore, the chips in higher water concentrations will have a larger mass than in higher sugar concentrations. Further information on potato plant cells: Plant cells always have a strong cell wall surrounding them. When they take up water by
Potato and osmosis Investigation.
GCSE Biology- Osmosis Coursework Potato and osmosis Investigation Planning Aim: To investigate the osmotic activity which occurs when the concentration of a certain sugar solution is varied and the effect this has on potato chips. I must conclude this investigation by verifying the connection with the water potential/concentration of solution on potato chips (if there is one). Hypothesis: Osmosis is defined as the net movement (diffusion) of water or any other molecules or solutions from an area of high concentration to an area of low. This movement must take place across a partially permeable membrane such as a cell wall, which lets in smaller molecules like water but does not allow bigger molecules to pass through. The molecules will continue to diffuse until the area in which the are found reaches a state of equilibrium, meaning that the molecules are randomly distributed throughout an object, with no area having higher or lowers concentration than any other. Osmosis makes plants cells swell up if there're surrounded by weak solution ad they become (Turgid). This is real useful for giving support to green plant tissue and for opening stomata guard cells. Animal cells don't have a cell wall and can easily burst if put into pure water because they take in so much water by osmosis. When a Plant is well watered, all its cells will draw water into themselves by osmosis
Potato Chip Experiment.
Potato Chip Experiment Preliminary Practical Work: In the preliminary work I used two potatoes and two different solutions, Sucrose and Water. I cut obtained the potato by using a cork borer and then made sure that they had the same or nearly the same mass and took down the masses. I put the two chips in test tubes and in one test tube I put water and in the other I put Sucrose. I used 4.5 centimetre cubed of both solutions. I left both of the solutions for 24 hours and then dried the chips and took down the end mass of them. I noticed that the mass of the potato chip in the sucrose solution and decreased and that the mass of the chip in the water had increased. Results table for preliminary: Solution Start Mass (g) End Mass (g) Difference in mass Percentage Change (%) Sucrose 0.5 .67 .91 0.24 4.37 Distilled Water .70 .51 -0.19 1.18 From these results I can see that the potato sucrose solution decreased in mass and the potato in water increased. I have decided from these results that I will use the same amount of sucrose and water solution in the test tubes because it covers the potato. I have decided because I will be using more pieces of potato in my real experiment I will need to use the same potato for all the pieces so I will make my potato chips small to use less potato. This means they will weigh about half as much as they did in the preliminary
To investigate the effect of varying concentration of a certain sugar solution on the amount of osmotic activity between the solution and a potato chip of a given size.
Skill Area P: Planning Aim: To investigate the effect of varying concentration of a certain sugar solution on the amount of osmotic activity between the solution and a potato chip of a given size. Hypothesis: Osmosis is defined as the net movement of water or any other solution¡¦s molecules from a region in which they are highly concentrated to a region in which they are less concentrated. This movement must take place across a partially permeable membrane such as a cell wall, which lets smaller molecules such as water through but does not allow bigger molecules to pass through. The molecules will continue to diffuse until the area in which the molecules are found reaches a state of equilibrium, meaning that the molecules are randomly distributed throughout an object, with no area having a higher or lower concentration than any other. For this particular investigation I think that the lower the concentration of the sugar solution in the test tube the larger the mass of the potato will be. This is because the water molecules pass from a high concentration, i.e. In the water itself, to a low concentration, i.e. In the potato chip. Therefore, the chips in higher water concentrations will have a larger mass than in higher sugar concentrations. The graph above shows a simple curve obtained when the concentration of the solution is plotted against the percentage change in
To investigate the effect of varying concentration of a certain sugar solution on the amount of osmotic activity between the solution and a potato chip of a given size.
Biology Coursework Aim: To investigate the effect of varying concentration of a certain sugar solution on the amount of osmotic activity between the solution and a potato chip of a given size. Hypothesis: Osmosis is defined as the net movement of water or any other solution's molecules from a region in which they are highly concentrated to a region in which they are less concentrated. This movement must take place across a partially permeable membrane such as a cell wall, which lets smaller molecules such as water through but does not allow bigger molecules to pass through. The molecules will continue to diffuse until the area in which the molecules are found reaches an isotonic point, a state of equilibrium. This means that the molecules are randomly distributed throughout an object, with no area having a higher or lower concentration than any other; this will help me identify my aim because the isotonic point will be the most accurate place to see an average change in mass. For this particular investigation, I think that the lower the concentration of the sugar solution in the cup the larger the mass of the potato will be. This is because the water molecules pass from a high concentration, i.e. in the water itself, to a low concentration, i.e. in the potato chip. Therefore, the chips in higher water concentrations will have a larger mass than in higher sugar
