"Separating colors in leaves using Chromatography"
YEAR 10 SCIENCE SCIENCE RESEARCH PROJECT "Separating colors in leaves using Chromatography" by Sebastien Hammond 10D INTRO: Chromatography is a technique that is used to separate the substances present in a mixture. It is also widely used to determine the identity of a substance; particuly organic compounds. In paper chromatography absorbant paper, in this case filter paper, is used as the stationary phase. A solution of the sample that is to be analysed, in this case leaves and leaf mixtures, is made up and placed onto one end of the paper as a small spot of the mixture. The position of the spot is known as the 'origin'. For paper chromatography the components of a mixture can be identified by the distance they travel along the stationary phase compared to the distance travelled by the solvent, in this case isopropyll. This is known as the Rf value and is expressed as. Distance moved from origin by mixture Rf = Distance moved from origin by solvent Each component has a characteristic Rf value for the conditions under which the chromatogram was obtained. By comparing the Rf values of the components of a particular mixture with the Rf values of a known substance under identical conditions, the compounds present in a mixture can be identified. AIM: to compare and analyse the colors and Rf levels of single leaves and a combination of leaves before and after
Osmosis, My aim for this experiment is to see the results of potato tissue's mass difference, when placed in different concentrations of sugar solutions. Variables involved:
Osmosis Background Information Osmosis is defined as the movement of water molecules from an area of high water concentration to an area of low water concentration, across a semi-permeable membrane. In a high concentration of water the amount of solute (e.g. sugar) is low. This could be called a weak or dilute solution. In a low concentration of water the amount of solute (e.g. sugar) is high. This could be called a strong or concentrated solution. When two such solutions are divided by a semi-permeable membrane the water will move from the area of high concentration to the area of low concentration, until both sides are equal (have reached equilibrium). This can be seen in living cells. The cell membrane in cells is semi-permeable and the vacuole contains a sugar/salt solution. So when a cell is placed in distilled water (high water concentration) water will move across the semi-permeable membrane into the cell (lower water concentration) by osmosis, making the cell swell. This cell is now referred to as turgid. If done with potato cells the cells would increase in length volume and mass because of the extra water. If these potato cells were placed in a solution with a low water concentration, then the opposite would happen. Water would move out of the cell into the solution. In extreme cases the cell membrane breaks away from the cell wall and the cell is referred to
Find out what factors affect the rate of photosynthesis. Rate being the amount of photosynthesis produced per minute.
Aim: To find out what factors affect the rate of photosynthesis. Rate being the amount of photosynthesis produced per minute. Variables: Equation for Photosynthesis: Representing sunlight Co2 + H2O Glucose, ATP and O2 - Temperature. Because Photosynthesis is an enzyme based reaction and enzymes dependant on the temperature. As we know, enzymes work better when the temperature increases, and they can be frozen if the temperatures are too low. However, when the temperature is too high, the enzymes could denature and therefore the plant would die and no photosynthesis would occur at all. - Light intensity, Because sunlight is needed for photosynthesis to occur. Sunlight is needed for the plant to turn into food. This process is Photosynthesis, so without Sunlight, there is no photosynthesis. So then this basically means if u give the plant more sunlight (higher light intensity), there is more photosynthesis to make more food. - Concentration of Co2 in water. Because Co2 is needed for Photosynthesis to occur. So then if there were a higher supply of Co2, there would be more photosynthesis. Therefore the concentration of Co2 in the water is able to affect the rate of photosynthesis. - Amount of water. Because water is needed for photosynthesis to occur. Without water, a plant cannot
Investigate the relationship between light intensity and the rate of photosynthesis.
Photosynthesis- year 10 Investigation. Investigate the relationship between light intensity and the rate of photosynthesis. Photosynthesis is important because animals eat food, as it is a source of energy. All living things need a constant supply of energy if they are to grow, reproduce or move. Plants do not eat food but they do have some in the form of starch in their leaves. The symbol equation for photosynthesis is: 6 CO2+6 H2O-light C6 H12 06+6 02. There are four substances needed for photosynthesis to tae place: -Carbon dioxide. -Chlorophyll. -Oxygen. -Sunlight. Photosynthesis cannot take place without all four of these substances being present. As light is the factor I am exploring in this investigation, that is the main factor I am looking at. Plants need light for photosynthesis to take place; photosynthesis will not take place in the dark. It is true that the brighter the light, the greater the rate of photosynthesis. Many plants have their leaves spread out in such a way that each leaf has as much light as possible and the lower leaves are not shaded by the ones above. I am investigating the effects of light on the rate of photosynthesis. It is possible to do this by measuring the rate of photosynthesis at different light intensities by counting the number of bubbles of gas given off by the plant in a given time. To make the test fair I will use
Enzymes at work
Enzymes at work The aim of my investigation is to find out what pH the enzyme named peroxidase works best at. We can find the enzyme peroxidase if we grind up celery, or most other animal and plants. A chemical reaction in plants and animals produce hydrogen peroxide, this can poison them if it is allowed to accumulate. The enzyme peroxidase acts as a catalyst for decomposing hydrogen peroxide, it is broken down into water and oxygen. The reaction is: 2H20 = 2H20 + O2 (Aq) (L) (G) I plan to measure the amount of oxygen given off by the celery at different pHs and whichever pH helps the enzyme produce the most oxygen. Before I do this I must do a preliminary plan to see what my other variables should be so that I can get the best results. I predict that the optimum pH will be around 7 because if it goes any lower or higher than this it could change the enzymes shape and/or charge properties of the substrate so that either the substrate cannot bind to the active site or it cannot undergo catalysis. Different enzymes have different optimum pHs and it is hard to say what it will be because some enzymes work best at low temperatures and others at high temperature. As you can see from the graph the two different enzymes, represented by red and green lines, have a different optimum pH. When the pH is altered is will become denatured or it may be optimum it depends
Hydrological Cycle
Hydrological Cycle The hydrological cycle is a constant movement of water above, on, and below the earth's surface. It is a cycle that replenishes ground water supplies. It begins as water vaporizes into the atmosphere from vegetation, soil, lakes, rivers, snowfields and oceans-a process called evapotranspiration. As the water vapour rises it condenses to form clouds that return water to the land through precipitation: rain, snow, or hail. Precipitation falls on the earth and either percolates into the soil or flows across the ground. Usually it does both. When precipitation percolates into the soil it is called infiltration when it flows across the ground it is called surface run off. The amount of precipitation that infiltrates, versus the amount that flows across the surface, varies depending on factors such as the amount of water already in the soil, soil composition, vegetation cover and degree of slope. Surface runoff eventually reaches a stream or other surface water body where it is again evaporated into the atmosphere. Infiltration, however, moves under the force of gravity through the soil. If soils are dry, water is absorbed by the soil until it is thoroughly wetted. Then excess infiltration begins to move slowly downward to the water table. Once it reaches the water table, it is called ground water. Ground water continues to move downward and laterally through
The effect of insulating materials on heat loss from the body
The effect of insulating materials on heat loss from the body Richard Smith 5? Introduction In this experiment I will be testing six different materials, felt, cotton wool, bubble wrap, polystyrene, wool and cotton. The other variables, for example, the number of layers, the amount of water in the flask, and the size of the flask, will be fixed to enable a fair test. I will use 200 cm3 of water in the flask, which will be inside a beaker full of the insulating material. Prediction I think that the polystyrene will be the best insulator, because after looking at all the materials under a microscope, I found that polystyrene had the smallest air spaces. This means that the air in those spaces will take the least time to heat up and therefore less heat is lost in the heating. I think that the bubble wrap will be the worst insulator, because it has large air spaces, which will take longer to heat up. The order of best --> worst may look like this: polystyrene, felt, wool, cotton wool, cotton, bubble wrap. I think that the graph will look like this: - The heat is lost at first through conduction to the layers of insulation. That is why in my predicted graph I think there will be quite a rapid fall in temperature initially and then it will slow down. When the temperature drop starts to slow down that is when the insulating material is heated to roughly the same temperature as
The effect of sucrose solution concentration On osmosis in potato chips
The effect of sucrose solution concentration On osmosis in potato chips Plan I am going to cut six pieces of potato using a borer. They will all the same weight. I will make them all 0.7g. I will be able to make sure they are all the same weight-using scales. If a piece of potato is too big I will use a scalpel and a tile to trim it so they are all the same weight and then place these into a test tube each. I will hold the test tubes in a test tube rack. Using the measuring cylinder I will measure 10ml of each strength of sugar solution rinsing the measuring cylinder after each measure. This will then be added into separate test tubes with the pieces of potato. E.g. a piece of potato will have 0.0M strength; a piece of potato will have 0.2M strength and a piece of potato will have 0.4M strength etc. I will put a sticky label on each test tube stating what strength of sugar solution it contains. I will then leave these for 2 hours and see what happens then record my results. APPARATUS A potato Sugar solutions (0.0, 0.2, 0.4, 0.6, 0.8, and 1.0) Borer Scalpel Tweezers Scales 6 test tubes Test tube rack Measuring cylinder I will measure the amount of sugar solution in the test tubes. I will change the strength of sugar solution in each test tube. To make the experiment a fair test I will keep the weight of the pieces the same weight I will also only add the same
Investigation to work out the concentration in potato cell sap
Sarah Carr Biology Coursework 2001 Investigation to work out the concentration in potato cell sap Preliminary work As an introduction to osmosis, an experiment was carried out with a model cell. The model cell experiment shown how osmosis occurs, demonstrated with two cells - Cell A Cell B Water diffuses into 'cell' Water diffuses out of 'cell' Visking Visking Tubing Tubing (Partially (Partially Permeable Permeable Membrane) Membrane) Cell A was filled with sugar solution, cell B was filled with water, and then the two cells were weighed. Cell A was placed into a beaker of water and cell B was placed into a beaker of sugar solution. They were both left for 30 minutes, and then the cells were weighed again. It was discovered that cell A (containing sugar solution), increased in weight. This was because water was allowed to pass into the cell and into the strong solution by osmosis. Therefore cell B, decreased in weight because water had passed out of the cell and into the strong solution by osmosis again. As it has been identified that cells can increase in weight with osmosis, it is fair that we can say cells of a potato core will behave in the same way as the model cell. Aim My aim is to work out the concentration in potato cell sap. I am to find the increase/decrease in weight of
Investigation on Heat Loss in Organisms.
Investigation on Heat Loss in Organisms Introduction: Heat loss is extremely important for all types of organism is any habitat. The temperature of the body has to be correct otherwise the organism will not be able to survive, so it is vital that organisms can control factors to keep their body temperature at a safe, constant temperature. Heat loss is so vital because it can easily kill an organism its temperature rises or decreases by a certain amount, which could easily happen under the worlds varying climate. In a cold habitat, obviously there is not a lot of heat to be gained outside, so the heat inside the body of an organism has to be kept by other methods, to keep the body temperature constant and at a safe temperature. One method, is having a layer of fat to maintain the heat already inside their bodies. However, a more important and influential fact, is that in cold places such as the Arctic, you tend to only find large animals, such as Polar Bears, and Penguins, with the smallest organisms being Arctic Foxes. This means that they have less skin per cm3 of volume - and so have a smaller surface area : volume ratio. This means that through their skin, they loose less heat than that of smaller organisms, who have more skin per cm3 of volume. So, these larger animals loose less body heat and so are suited to the colder conditions of the arctic. The
