effects of substrate concentration on the activity of the enzyme catalase.
Investigate the effects of substrate concentration on the activity of the enzyme catalase. To explain this, catalase is an enzyme found in potato cells, catalase breaks down the substrate Hydrogen-Peroxide into water + oxygen. Hydrogen Peroxide itself is a waste product found in potatoes and other fruit + vegetables. When I do this I will see with different concentrations of the substrate and see how quick the enzyme catalase works on it. The four things that affect the rate at which the substrate and enzyme would react are as follow:- * Susceptibility of temperature change. * Susceptibility to PH changes. * Enzyme concentration. * Substrate concentration. Now I will explain each one of these in detail and how they can change the rate of reaction in many different ways. Susceptibility of temperature: - Chemical reactions can be speeded up by heating the reactants, this makes molecules speed up and have sufficient energy for more successful collisions. If the temperature is too high the enzyme would vibrate and it would denature because the active-site would change shape. Susceptibility of PH changes: - Enzymes can be denatured by changes in PH. This happens because the ionisation of the Amino acids changes, the Ionic bonds with stabilise the enzyme, that shape is broken so they are no longer stable. So you need the right PH for the ionic bonds to stay stable for the
Investigation to find the effect of different concentrations of sugar Solutions on osmosis.
Investigation to find the effect of different concentrations of sugar Solutions on osmosis. Introduction Osmosis is the diffusion of water molecules from a place where they are in a higher concentration (such as a dilute sugar solution), to a place where the water molecules are in a lower concentration (such as a concentrated sugar solution) through a semi-permeable membrane. Dilute Sugar Solution Concentrated Sugar Solution Water movement This is a diagram to illustrate a concentrated sugar solution, separated from dilute sugar solution by a membrane. The membrane had pores, which are very small. The water molecules are small compared to the sugar molecules. The pores are big enough to let the water molecules through but not the sugar molecules. It is called a semi-permeable membrane because it will let some molecules through but not others. The water molecules will move from the left-hand-side to the right-hand-side from an area of high concentration of water to a low concentration of water. Factors affecting osmosis * Concentration of external solution * Volume of external solution * Type of external solution * Surface area of tissue * Type of tissue * Mass of tissue Independent Variable In this experiment I have chosen to change the concentration of the external solution throughout the experiment. I will do this by changing the
To investigate the different effects of various concentrations of sucrose solution on potato cells.
Aim: to investigate the different effects of various concentrations of sucrose solution on potato cells. Introduction: Osmosis is a special type of diffusion. Osmosis happens when two solutions of different concentrations are separated by a selectively permeable membrane. A selectively permeable membrane has holes in it which are just big enough for water molecules to pass through, but not the much larger sugar molecules. Water moves across the membrane from a weak solution (high concentration of water molecules) to a stronger solution (lower concentration of water molecules). In this case, the two solutions are the cytoplasm inside the potato cells and the sucrose solution that I am placing my potato chip in. The partially permeable membrane is the cell membrane of the potato cells. When potato chips are placed in pure water, the concentration of water molecules surrounding the plant is higher than the concentration of water molecules inside the cytoplasm of the potato's cells. The water will diffuse into the cell and the cytoplasm by osmosis. This means the cytoplasm pushes out against the cell wall as it expands slightly and the cell becomes firm or turgid. The overall effect over time is for each cell to increase slightly in mass and so the whole potato chip shows an increased mass. However, if you put a piece of potato into a sugar solution (where the water
Stephen Blackpool: The Pathetic Figure.
Apiwan Kiewchawum 4406611105 LT. 356 Stephen Blackpool: The Pathetic Figure Charles Dickens's Hard Times is one of the most important novels in the Victorian Age. He presents an industrial society in nineteenth century in England. In this age, England prospers in manufacture and trade because of high technologies. It is also a time of trouble. Industrial development causes terrible conditions of a working class. The workers are poor and work hard. Women and children work for many hours. Dickens also presents bad social condition through his work and also shows lives of city people and industrial society in Coketown in England. In Hard times, Dickens has a compassion for the workers and calls for the readers' sympathy by showing the workers' hardships through Stephen Blackpool, a worker who is honest, innocent, generous and full of integrity. However, facing dead-end situations, Stephen Blackpool is the most pathetic figure. Stephen Blackpool is the most suffered and submissive worker. Although he is good, skilful and diligent power-loom weaver, his life is not much improved, but he has to work for survival. Dickens presents that most of Coketown citizens are workers. He says that they are " generically called ' the Hands'- a race who would have found more favor with some people, if the Providence had seen fit to make them only hands, or, like the lower creatures of the
Investigate the effect of osmosis on the potato cylinders of a certain size in different concentrations of solution.
Biology Coursework Osmosis Obada Sawalha Year 10 BCB Aim: To investigate the effect of osmosis on the potato cylinders of a certain size in different concentrations of solution. Hypothesis: * Water will flow from the low concentration to the high concentration. * The cylinders in high concentration solution will gain and increase in mass. * The cylinders in low concentration solution will loose and decrease in mass. Scientific Knowledge: Osmosis: Osmosis, which is regarded as a form of diffusion, is defined as the net movement of water or any small molecule across a partially permeable membrane from a region of low concentration to a region of higher concentration. Partially permeable membranes are very thin layers of material (cell membranes are partially permeable) which allow some things to pass through them but prevent other things from passing through. Partially permeable membranes will allow small molecules like Oxygen, water, Carbon Dioxide, Ammonia, Glucose, amino-acids, etc. to pass through. Cell membranes will not allow larger molecules like Sucrose, Starch, protein, etc. to pass through. Turgor: When osmosis occurs in a plant cell after it has been watered the water (which is less concentrated) enters the vacuole which therefore results in that the vacuole is erected to its full size, this is called turgidity. When all cells in the plant are turgor
Investigate osmotic effects on plant cells
Investigate osmotic effects on plant cells Introduction Water is not only the medium in which metabolic reactions occur but it provides skeletal support and thus is vital for plants. Animal cells are not used to demonstrate osmotic effect in this study because it would raise moral and ethical issues in regards to animal rights and the use of animals in scientific experimentation. Also animal cells don't have cell walls so if they were in dilute solutions the cell membrane would expand and eventually split. This type of change due to osmosis would be difficult to measure. A plant cell (fig 1) maintains its shape due to the cell wall being rigid and the cell wall pushing outwards onto it. Water will enter a cell by osmosis. Osmosis is the movement of water molecules from a dilute solution to a concentrated solution through a selectively permeable membrane (fig 2). When a plant cell gains water the vacuole expands causing the cell to stretch and become larger. The cell is turgid (fig 3). This occurs when the cell is surrounded by a more dilute solution. If a plant cell is put in a more concentrated solution then what is in, its vacuole becomes flaccid. The cell is plasmalysed. This is because water travels from a dilute solution to a concentrated solution by osmosis. The vacuole then shrinks causing the pressure inside the cell to reduce and the cell gets shorter (fig 4).
I aim to discover how temperature affects the rate of reaction with a potato. I will be able to do this by placing potato pieces of equal size into test tubes with hydrogen peroxide in
Biology Coursework: 3/5/2006 Investigating the Rate of Reaction. Introduction: In this investigation I aim to discover how temperature affects the rate of reaction with a potato. I will be able to do this by placing potato pieces of equal size into test tubes with hydrogen peroxide in. Then I will plot my results onto a graph and work out line of best fit. This will give me the evidence , so I can see what temperature affects the rate of reaction most. Investigation: Introduction: I have conducted this investigation to examine the change of potato 'chips' in 3 different temperatures. This will give good help on my Hypothesis. I can alter any variables if any problems occur with the ones I am using example, Potato strip size, amount of hydrogen peroxide, and apparatus used. Apparatus * One potato. * A Beaker. * Safety goggles. * Three test tubes. * A test tube rack. * A cutting tile. * A cutting knife. * Water. * A Ruler. * A Stop Watch. * Thermometer Apparatus: Notes: * Test Tube rack so I can watch an keep the experiments steady and safe the results will be more accurate. * The cutting tile prevents the surface from getting damaged and a ruler can be used to cut the potato strips for more accuracy. Method: ) Cut out 3 strips of potato (from the same potato to ensure a fair test). 2) Cut the 3 strips to equal length (4cm), and measure and
The aim of this experiment is to see how varying the concentration of a sugar solution affects the osmotic activity between the solution and a potato chip.
Experiment Investigating Osmosis in Potato Chips Skill Area P-Planning The aim of this experiment is to see how varying the concentration of a sugar solution affects the osmotic activity between the solution and a potato chip. Hypothesis and Background information on Osmosis The term Osmosis means 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, which lets smaller molecules such as water through but does not allow bigger molecules to pass through such as sugar. In my experiment I predict that the lower the concentration of the sugar solution in the test tube the larger the mass of the potato will be and vice versa. 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. I predict that if I double the strength of the solution I should loose double the amount of water. Plant cells are where osmosis takes place, when a plant cell is placed in water they start to swell, due to osmosis, but the cell wall prevents them from bursting. Plant cells eventually become "turgid" when they are put in dilute
To investigate the effect of temperature on catalase.
How temperature effects the breakdown of hydrogen peroxide by the enzyme catalase Aim: To investigate the effect of temperature on catalase An enzyme is a protein molecule that speeds up chemical reactions in all living things, without enzymes these reactions would be to slow or would not happen. Enzymes are also useful because they cannot be used up and does not affect the reaction in any other way. My experiment will be testing the affect of temperature on catalase. I will need to try and keep these constant for the experiment to be fair: . PH: if the pH is too high or too low the enzymes will become denatured because of the loss of H+ ions at too high PH, and the gain of H+ ions when the pH is low. 2. Concentration of enzyme: The higher the concentration, the more successful collisions occur and the higher the rate of reaction. I will try to keep the same concentration of enzymes by using the same volume of potato. c) Surface area: If the surface area is larger there will be more successful collisions. I will try and keep this constant by measuring and cutting accurately. Kinetic theory states that when a substance is heated, energy is given to the particles and they vibrate faster. Therefore when heat is applied to an enzyme and substrate, the particles speed up, increasing the rate of successful collisions with each other. This would suggest that the rate of
The aim of this experiment is to investigate how changing the concentration of a solution will affect the rate of osmosis. I intend to use different concentrations of a sugar solution to provide my variable and a potato for my living organism.
Introduction: The aim of this experiment is to investigate how changing the concentration of a solution will affect the rate of osmosis. I intend to use different concentrations of a sugar solution to provide my variable and a potato for my living organism. Hypothesis: I plan to leave potato slices in various concentrations of sugar solution. My prediction is that the higher the sugar concentration is, the lesser the potato would weigh. This is because the potato contains more water than the glucose solution therefore it leaves the potato and goes into the solution in an attempt to even up the concentration on each side of the membrane. Biological Knowledge: Osmosis is the movement of water molecules across a partially permeable membrane from a region of high water concentration to a region of low water concentration with the intent of reaching equilibrium. A partially permeable membrane has very small holes. They are so small that they can only allow water molecules to pass through unlike bigger molecules such as glucose. An example of a partially permeable membrane is a Visking Tube. The water molecules actually pass both ways through the membrane. Because there are more on one side than the other there's a steady net flow into the region with fewer water molecules for example into a stronger solution (in this case sugar solution). This causes the region with a lot of
